CN103180751A - Arrival angle calculation device - Google Patents

Abstract

The purpose of the present invention is to provide an arrival angle calculation device that can calculate an arrival angle to a high degree of accuracy. This arrival angle calculation device (1) comprises a plurality of antennae, a plurality of received signal processing units, and an arrival angle calculation unit. Each of the received signal processing units comprise reception units (12a, 12b), correlation processing units (21a, 21b), peak detection units (22a, 22b), and timing control units (23a, 23b). The timing control units (23a, 23b) are characterised in that when the ratio between the power of the peak period in a period corresponding to an information unit and the power of a period excluding the peak period is larger than a threshold value, signals from the correlation processing units (21a, 21b) are output to an arrival angle calculation unit (24).

Description

Arrive the angle calculation element

Technical field

The present invention relates to detect arrival electric wave phase place and be used for the arrival angle calculation element of the calculating of angle of arrival degree.

Background technology

In arrival direction estimation unit in the past, the large computings of operand such as the calculating of use cross-correlation coefficient, inverse matrix computing need the computing of hundreds of symbol weight.Therefore, wish to obtain to estimate the arrival direction estimation unit of arrival direction by easy computing.

Proposed to have dwindled the arrival direction estimation unit of computing scale in patent documentation 1.In the arrival direction estimation unit that patent documentation 1 is put down in writing, to by two antenna receptions to the reception signal, calculated the coefficient of arrival direction by complex conjugation circuit and mlultiplying circuit, by carrying out arctangent cp cp operation and arc cosine computing in the arrival direction testing circuit, and estimated to receive the arrival direction of ripple.

The prior art document

Patent documentation

Patent documentation 1: Japanese kokai publication hei 10-177064 communique

Summary of the invention

The problem that invention will solve

But, in patent documentation 1, the power that has adopted the arrival direction vector between 1 slot relatively and threshold value and in the situation that than the formation of the large renewal of threshold value arrival direction, therefore, the expectation ripple that might detect exactly in the reception ripple upgrades arrival direction.For example, in the situation that it is high to receive the background value of ripple, with the signal level of expectation ripple irrespectively, the power that receives ripple is often large than threshold value.In this case, arrival direction is also calculated, is upgraded under background value, therefore can not correctly estimate arrival direction.

The present invention carries out in view of such point, and its purpose is to provide a kind of impact that can suppress to receive the background value of ripple, and can arrives with high precision computation the arrival angle calculation element of angle.

Be used for solving the means of problem

arrival angle calculation element of the present invention is characterised in that to possess: a plurality of antennas receive the electric wave that sends from certain position, a plurality of reception signal processing parts arrange accordingly with described each antenna, and arrival angle calculating part, thereby be taken into from the output signal by described a plurality of reception signal processing part outputs the arrival angle that the component of signal that becomes identical information unit between the reception signal processing part is calculated described electric wave, the described signal processing part that respectively receives possesses: acceptance division, will by the described antenna reception of correspondence to electric wave be transformed to reception signal and the output of the phase information with this electric wave, correlation processing unit will be carried out relevant treatment from the reception signal of described acceptance division output, the peak value test section, the peak value of the reception signal of described relevant treatment has been carried out in detection, and timing control part, cut out the mode that becomes the component of signal of identical information unit between described reception signal processing part with the output signal from described correlation processing unit, match with the timing of the peak value that is detected by described peak value test section, thereby control being taken into regularly from the output signal of described correlation processing unit output, in the situation that the electric power between the peak period in during suitable with described information unit and except between this peak period during the ratio of electric power greater than threshold value, described timing control part will be exported to described arrival angle calculating part from the signal of described correlation processing unit.

According to this formation, ratio and threshold with the electric power during beyond the electric power between the peak period and its, in the situation that arrive angle than calculating greater than threshold value, even therefore in the situation that the signal level beyond the expectation ripple of reception ripple is high, also can detect exactly the peak value of expectation ripple, and calculate the arrival angle.That is, do not calculate according to the part beyond the expectation ripple and arrive angle, therefore can improve the computational accuracy that arrives angle.

In arrival angle calculation element of the present invention, also can for, with ∑ P ₁With ∑ P ₂Than ∑ P ₁/ ∑ P ₂Compare with threshold value, described than ∑ P ₁/ ∑ P ₂In situation greater than described threshold value, described timing control part will be exported to described arrival angle calculating part from the signal of described correlation processing unit, wherein above-mentioned ∑ P ₁Electric power sum between the peak period in during suitable with described information unit, above-mentioned ∑ P ₂Electric power sum in during in during suitable with described information unit except between the described peak period.

In arrival angle calculation element of the present invention, also can for, described arrival angle calculating part possesses: complex conjugate section, fetch the complex conjugate of signal of timing control part of the reception signal processing part of My World, and this side's reception signal processing part is corresponding with a side antenna; Complex multiplication section, with the output of described complex conjugate section with from the signal multiplication of the timing control part of the opposing party's reception signal processing part, this opposing party's reception signal processing part is corresponding with the opposing party's antenna; Arc tangent section carries out arctangent cp cp operation with the output of described complex multiplication section, calculates the phase differential of the described reception electric wave between described antenna; Equalization section averages the output of described arc tangent section; And arrive the angle transformation component, carry out the inverse trigonometric function computing with the output of described equalization section, thereby be transformed to the arrival angle.Consist of according to this, can not use the calculating, inverse matrix computing etc. of cross-correlation coefficient and calculate and arrive angle, therefore can dwindle the scale that arrives the angle calculation device.

In arrival angle calculation element of the present invention, also can for, the described phase differential that calculates distribute in the situation that on the I-Q plane+180 ° and/or-180 ° near, described arrival angle calculating part averages after making each phase differential rotation predetermined angular, carry out the inverse trigonometric function computing after this mean value deducts described predetermined angular, thereby be transformed to the arrival angle.Consist of according to this, distribute at phase differential in the situation that arrive the phase differential zone that the computational accuracy of angle is in the tendency of reduction, make phase differential only rotate predetermined angular and arrive the computing of angle calculation, the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

In arrival angle calculation element of the present invention, also can for, on described I-Q plane, in the situation that greater than+90 ° or less than the quantity of the phase differential of-90 ° than less than+90 ° and Duo greater than the quantity of the phase differential of-90 °, be judged as be distributed on described I-Q plane+180 ° and/or-180 ° near.

In arrival angle calculation element of the present invention, also can for, make described predetermined angular for+90 ° ,-90 ° ,+any angles of 180 ° or-180 °.

In arrival angle calculation element of the present invention, also can for, in the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by changed the arctangent cp cp operation of the relation of I component and Q component after the symbol of described Q component that reversed, come the phase differential after calculation correction, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value deducts 90 °, thereby be transformed to the arrival angle.According to this formation, distribute at phase differential in the situation that arrive the phase differential zone that the computational accuracy of angle is in the tendency of reduction, make the amount of phase differential rotation predetermined angular and arrive the computing of angle calculation, the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

In arrival angle calculation element of the present invention, also can for, in the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by changed the arctangent cp cp operation of the relation of I component and Q component after the symbol of described I component that reversed, come the phase differential after calculation correction, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value is added 90 °, thereby be transformed to the arrival angle.According to this formation, distribute at phase differential in the situation that arrive the phase differential zone that the computational accuracy of angle is in the tendency of reduction, make the amount of phase differential rotation predetermined angular and arrive the computing of angle calculation, the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

In arrival angle calculation element of the present invention, also can for, in the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by carry out the phase differential after arctangent cp cp operation is come calculation correction after the symbol of the symbol of the described I component that reversed and Q component, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value deducts 180 °, thereby be transformed to the arrival angle.According to this formation, distribute at phase differential in the situation that arrive the phase differential zone that the computational accuracy of angle is in the tendency of reduction, make the amount of phase differential rotation predetermined angular and arrive the computing of angle calculation, the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

The invention effect

According to arrival angle calculation element of the present invention, obtain between the peak period electric power and between the peak period beyond remaining during in the ratio of electric power, this ratio and threshold value of obtaining is compared, in the situation that arrive angle than calculating greater than threshold value, even therefore in the situation that the signal level beyond the expectation ripple of reception ripple is high, also can detect exactly the peak value of expectation ripple, and calculate the arrival angle.That is, do not calculate according to the part beyond the expectation ripple and arrive angle, therefore can improve the computational accuracy that arrives angle.

Description of drawings

Fig. 1 means the block diagram of the configuration example of the arrival angle calculation element that embodiment relates to.

Fig. 2 means the block diagram of the concrete formation (DSSS) of the arrival angle calculation element that embodiment relates to.

Fig. 3 means the figure of example of the output waveform of totalizer.

Fig. 4 (a) means the figure of example of the output waveform of arc tangent section, (b) means the figure of example of the output waveform of power system calculation section.

Fig. 5 means the schematic diagram of the geometry relation of the electric wave that arrives antenna.

Fig. 6 means the schematic diagram of the example that comprises the position detecting system that arrives the angle calculation device.

Fig. 7 is the process flow diagram that arrives the arrival angle calculation in the angle calculation element.

Fig. 8 is the schematic diagram to the signal of peak value test section input.

Fig. 9 means in the situation of using DSSS as modulation system to the schematic diagram of the example of the signal of peak value test section input.

Figure 10 means the schematic diagram of the example of the signal that the peak value test section in the situation that has been taken into the reception signal to using the AD transducer is inputted.

Figure 11 means other the routine block diagram that arrives the angle calculating part.

Figure 12 means the schematic diagram of the computer capacity of phase differential.

Figure 13 means the schematic diagram of example of the phase data of calculating.

Figure 14 means that phase differential becomes+schematic diagram of the summary of arrival angle calculation near 180 ° or-180 ° situation.

Figure 15 is that phase differential becomes+process flow diagram of arrival angle calculation near 180 ° or-180 ° situation.

Figure 16 means other the routine block diagram that arrives the angle calculating part.

Figure 17 means the block diagram of the concrete formation (OFDM) of the arrival angle calculation element that embodiment relates to.

Figure 18 (a) means the schematic diagram of the formation of the symbol in OFDM, (b) means the schematic diagram of situation of the relevant treatment of OFDM symbol string.

Figure 19 (a) (b) means figure from the example of the output waveform of power system calculation section, (c) means the figure from the example of the output waveform of adder, (d) means the figure from the example of the output waveform of the each several part of arc tangent section.

Figure 20 means the schematic diagram of the configuration example of having used the capsule endoscope system that arrives the angle calculation element.

Embodiment

Fig. 1 means the block diagram of the configuration example of the arrival angle calculation element that one embodiment of the present invention relates to.The arrival angle calculation element 1 that present embodiment relates to possesses: reference signal generating unit 10, and can be with the oscillation frequency vibration reference signal of regulation; Antenna for receiving 11a, 11b separate predetermined distance ground configuration; Acceptance division 12a, 12b use will to be transformed to by the electric wave that antenna for receiving 11a, 11b accept from the reference signal of reference signal generating unit 10 outputs to receive signal and output; And operational part 13, carry out for the various calculation process that arrive angle calculation according to the reception signal from acceptance division 12a, 12b output.In addition, arrive angle calculation element 1, the phase place that causes according to the propagation delay by electric wave lags behind to calculate the arrival angle, therefore need to receive the electric wave with identical information separating two points of predetermined distance (or the point more than two).Antenna and the receiving system that therefore, need to possess two (or more than them) corresponding with receiving electric wave.In addition, as long as can receive identical arrival electric wave (identical information unit) in the position more than two that separates predetermined distance, arrive the formation that angle calculation element 1 is not limited to possess the receiving system more than two.

Acceptance division 12a, 12b constitute and comprise low noise amplifier, frequency mixer, bandpass filter etc., and constitute the electric wave that can receive assigned frequency.Operational part 13 constitutes and comprises: correlation processing unit 21a, 21b receive the relevant treatment of signal; Peak value test section 22a, 22b, the peak value of the reception signal of relevant treatment has been carried out in detection; Timing control part 23a, 23b coordinate the timing of the peak value that is detected by peak value test section 22a, 22b and export signal from correlation processing unit 21a, 21b; And arrive angle calculating part 24, according to the signal from timing control part 23a, 23b, arrive the calculating of angle.In addition, the formation of operational part 13, function can be realized by hardware, also can be realized by software.

Correlation processing unit 21a, 21b will and receive the high signal multiplication of signal correction and output with this from the reception signal of acceptance division 12a, 12b.The signal of being taken advantage of in correlation processing unit 21a, 21b and the relevant height that receives signal, therefore the signal from correlation processing unit 21a, 21b output becomes peak value at related interval.Peak value test section 22a, 22b calculate the electric power from the output signal of correlation processing unit 21a, 21b, and detect the electric power peak value of output signal. Timing control part 23a, 23b are engaged in the peak value timing that detects in peak value test section 22a, 22b, and the output signal of the auto-correlation processing 21a of section, 21b is exported to arriving angle calculating part 24 in the future.Particularly, based on the information of calculating according to the electric power between the peak period of detecting, determine whether that the output signal of the auto-correlation processing 21a of section, 21b is exported to arriving angle calculating part 24 in the future.

Fig. 2 represents to use as modulation system the block diagram of the concrete configuration example of the arrival angle calculation element in the situation of direct spread spectrum (DSSS).In addition, only represented in Fig. 2 with Fig. 1 in the suitable formation of operational part 13.

In Fig. 2, correlation processing unit 21a possesses: the diffuse code generator 31 that diffuse code occurs; With multiplier 32a and the 32b that receives signal and diffuse code and multiply each other; And the output of multiplier 32a and 32b is added up to amount during 1 (bit) and to totalizer 33a and the 33b of peak value test section 22a and timing control part 23a output.Peak value test section 22a possesses: calculating is from the power system calculation 34a of section of the electric power of the signal of totalizer 33a and 33b output; And the peak value electric power test section 35a that detects its electric power peak value and export to timing control part 23a.Timing control part 23a possesses buffer unit 36a, could be to arriving 24 outputs of angle calculating part based on the signal of controlling from the signal of peak value electric power test section 35a from totalizer 33a and 33b.Equally, correlation processing unit 21b possesses diffuse code generator 31, multiplier 32c and 32d, totalizer 33c and 33d, and peak value test section 22b possesses the power system calculation 34b of section, peak value electric power test section 35b, and timing control part 23b possesses buffer unit 36b.Arriving angle calculating part 24 possesses: the complex conjugate complex conjugate section 41 of getting the output of buffer unit 36a; Complex multiplication section 42 with the output complex multiplication of the output of complex conjugate section 41 and buffer unit 36b; Carry out the arc tangent section 43 of arctangent cp cp operation with the output of complex multiplication section 42; Calculate the power system calculation section 44 of the interval electric power of each chip (chip) according to the output signal of complex multiplication section 42; According to from the information of the power system calculation section 44 equalization section 45 with the output equalization of arc tangent section 43; And be transformed to the output of equalization section 45 the arrival angle transformation component 46 that arrives angle.

Diffuse code generator 31 occurs to be used for expanding to by DSSS the diffuse code of the signal despreading on frequency axis.This diffuse code is corresponding with the diffuse code that uses when the transmitter side code is modulated (expansion).Multiplier 32a and 32b will receive above-mentioned diffuse code on signal times and carry out despreading.Input from the in-phase component I1 in the reception signal of acceptance division 12a to multiplier 32a.In addition, input from the quadrature component Q1 in the reception signal of acceptance division 12a to multiplier 32b.Totalizer 33a and 33b be output and the output of each chip interval of addition multiplier 32a and 32b in (position is interval) during suitable with 1.Fig. 3 (a) expression is from the example of the output waveform of totalizer 33a.Fig. 3 (b) is the part enlarged drawing of the output waveform shown in Fig. 3 (a).In addition, Fig. 3 (c) expression is from the example of the output waveform of totalizer 33b.Fig. 3 (d) is the part enlarged drawing of the output waveform shown in Fig. 3 (c).

The output signal of totalizer 33a and the output signal of totalizer 33b are inputted to the power system calculation 34a of section of peak value test section 22a and the buffer unit 36a of timing control part 23a.The 34a of power system calculation section calculates the electric power of each chip interval according to the output signal of totalizer 33a and 33b.Particularly, the absolute value addition of the absolute value of output signal of totalizer 33a that the 34a of power system calculation section will be suitable with in-phase component and the output signal of the totalizer 33b suitable with quadrature component is as the power information of each chip interval and export to peak value electric power test section 35a.Peak value electric power test section 35a when accepting the power information of each chip interval, detect to receive the electric power peak value in signal, as the electric power peak information and to the buffer unit 36a output of timing control part 23a.In addition, also can be with the square value addition of the output signal of the square value of the output signal of totalizer 33a and totalizer 33b and export to peak value electric power test section 35a.

From peak value test section 22a(peak value electric power test section 35a) the electric power peak information of output is judge to receive the information that has or not of the peak value of signal.Particularly, the electric power peak information is, expression receive near the peak point of signal during electric power sum ∑ P in (between the peak period) ₁And the electric power sum ∑ P in during beyond having removed between the peak period during 1 of the information unit from become DSSS ₂Ratio R(=∑ P ₁/ ∑ P ₂) whether greater than threshold value R _thInformation.In the electric power peak information, at R greater than R _thSituation under, timing control part 23a(buffer unit 36a) think that regularly receiving signal at this has peak value, and with the signal Ia1 of 1 amount and signal Qa1 to arriving 24 outputs of angle calculating part.On the other hand, at R less than R _thSituation under, timing control part 23a(buffer unit 36a) think that regularly receiving signal at this does not have peak value, and stop to the output that arrives angle calculating part 24.In addition, herein, peak value test section 22a has carried out the calculation process relevant with the electric power peak information, but also can carry out the calculation process relevant with the electric power peak information in timing control part 23a.

Correlation processing unit 21b(diffuse code generator 31, multiplier 32c and 32d, totalizer 33c and 33d), the peak value test section 22b(power system calculation 34b of section, peak value electric power test section 35b), timing control part 23b(buffer unit 36b) action, function, with above-mentioned correlation processing unit 21a(diffuse code generator 31, multiplier 32a and 32b, totalizer 33a and 33b), the peak value test section 22a(power system calculation 34a of section, peak value electric power test section 35a), timing control part 23a(buffer unit 36a) action, function same.Just, to the reception signal of correlation processing unit 21b input and reception signal to correlation processing unit 21a input, owing to receiving identical electric waves at 2 that are separating predetermined distance, so phase place is slightly different.Therefore, slightly different with the phase place of the signal of exporting from timing control part 23a from the signal of timing control part 23b output.When signal that will be suitable with in-phase component as real part, will be suitable with quadrature component signal showed the output O of timing control part 23a by plural number as imaginary part _a1, and the output O of timing control part 23b _a2The time, become following formula (1), (2) like that.In addition,

And

The phase place that represents each signal.

[formula 1]

$O_{a1}=\mathrm{Ia}1+\mathrm{<figure-callout\; id="1"\; label="iQa"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">iQa</figure-callout>}1={\mathrm{Ae}}^{i{\mathrm{\&phi;}}_1}={A\cos \mathrm{\&phi;}}_1+\mathrm{iA}\sin {\mathrm{\&phi;}}_1\&CenterDot;\&CenterDot;\&CenterDot;\left(1\right)$

[formula 2]

$O_{a2}=\mathrm{Ia}2+\mathrm{<figure-callout\; id="2"\; label="iQa"\; filenames="HDA00003110433600091.png,HDA00003110433600181.png"\; state="\{\{state\}\}">iQa</figure-callout>}2={\mathrm{Ae}}^{i{\mathrm{\&phi;}}_2}={A\cos \mathrm{\&phi;}}_2+\mathrm{iA}\sin {\mathrm{\&phi;}}_2\&CenterDot;\&CenterDot;\&CenterDot;\left(2\right)$

The output O of timing control part 23a _a1Be transfused to the complex conjugate section 41 that arrives angle calculation section 24.Complex conjugate section 41 is with the output O of timing control part 23a _a1Complex conjugate to 42 outputs of complex multiplication section.That is, from the complex conjugate 41 output signal Ia1 of section and with the sign-inverted of signal Qa1 signal.As the output O with complex representation complex conjugate section 41 _{A1 '}The time, become following formula (3) such.

[formula 3]

$O_{a{1}^{\&prime;}}=\mathrm{Ia}1-\mathrm{<figure-callout\; id="1"\; label="iQa"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">iQa</figure-callout>}1={\mathrm{Ae}}^{-i{\mathrm{\&phi;}}_1}=A\cos {\mathrm{\&phi;}}_1-\mathrm{iA}\sin {\mathrm{\&phi;}}_1\&CenterDot;\&CenterDot;\&CenterDot;\left(3\right)$

Complex multiplication section 42 is with the output O of complex conjugate section 41 _{A1 '}Output O with timing control part 23b _a2Complex multiplication, and will be as the signal Ib of multiplied result and signal Qb to arc tangent section 43 and 44 outputs of power system calculation section.The output O of complex multiplication section 42 _b, output O _bIn-phase component Ib and quadrature component Qb to be expressed as the formula of stating (4)～(6) such.

[formula 4]

$O_b={\mathrm{Ae}}^{-i{\mathrm{\&phi;}}_1}\&CenterDot;{\mathrm{Ae}}^{i{\mathrm{\&phi;}}_2}(={\mathrm{Be}}^{i({\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1)})$

$=(\mathrm{<figure-callout\; id="1"\; label="Ia"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">Ia</figure-callout>}1\&times;\mathrm{<figure-callout\; id="2"\; label="Ia"\; filenames="HDA00003110433600091.png,HDA00003110433600181.png"\; state="\{\{state\}\}">Ia</figure-callout>}2+\mathrm{<figure-callout\; id="1"\; label="Qa"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">Qa</figure-callout>}1\&times;\mathrm{Qa}2)+i(\mathrm{<figure-callout\; id="1"\; label="Qa"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">Qa</figure-callout>}1\&times;\mathrm{Ia}2-\mathrm{<figure-callout\; id="1"\; label="Ia"\; filenames="HDA00003110433600011.png,HDA00003110433600122.png"\; state="\{\{state\}\}">Ia</figure-callout>}1\&times;\mathrm{Qa}2)\&CenterDot;\&CenterDot;\&CenterDot;\left(4\right)$

[formula 5]

Ib=Ia1×Ia2+Qa1×Qa2 …(5)

[formula 6]

Qb＝Qa1×Ia2-Ia1×Qa2 …(6)

Arctangent cp cp operation is carried out in the output of 43 use complex multiplication sections 42 of arc tangent section.Particularly, carry out the arctangent cp cp operation of the value take the output signal Ib of complex multiplication section 42 as denominator, take output signal Qb as molecule.Fig. 4 (a) expression is from the example of the output waveform of arc tangent section 43.The output O of arc tangent section 43 _ArctanWith phase differential

Quite, represented by following formula (7).

[formula 7]

$O_{\arctan }={\tan }^{-1}\frac{\mathrm{Qb}}{\mathrm{Ib}}={\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1\&CenterDot;\&CenterDot;\&CenterDot;\left(7\right)$

The electric power of each chip interval calculates in power system calculation section 44 according to the output signal of complex multiplication section 42.Particularly, power system calculation section 44 is the absolute value addition of absolute value and the Qb of Ib, and as the power information of each chip interval and to 45 outputs of equalization section.In addition, also can be with the square value addition of the square value of Ib and Qb and to 45 outputs of equalization section.Fig. 4 (b) expression is from the example of the output waveform of power system calculation section 44.Equalization section 45 is when accepting the power information of each chip interval, according to the output O of this information with arc tangent section 43 _ArctanEqualization and to arriving 46 outputs of angle transformation component.In addition, power system calculation section 44 and equalization section 45 also can suitably omit.

Arrive the output that angle transformation component 46 uses equalization section 45 (in the situation that do not have equalization section 45, using the output of arc tangent section 43) and be transformed to the arrival angle by the inverse trigonometric function computing.As the inverse trigonometric function computing, for example, can use the inverse sine computing.The value, the output that namely arrives angle transformation component 46 and the arrival angle θ (rad) that are obtained by this computing are suitable.Arrive the output O of angle transformation component 46 _ArcsinRepresented by following formula (8).In addition, in following formula, λ (m) for receiving the wavelength of ripple, is d(m) distance between antenna for receiving.

[formula 8]

$O_{\arcsin }={\sin }^{-1}\frac{{\mathrm{<figure-callout\; id="43"\; label="O"\; filenames="HDA00003110433600021.png"\; state="\{\{state\}\}">O</figure-callout>}}_{43}}{2\mathrm{\&pi;}}\&CenterDot;\frac{\mathrm{\&lambda;}}{d}=\mathrm{\&theta;}\&CenterDot;\&CenterDot;\&CenterDot;\left(8\right)$

Obtaining arriving angle by above-mentioned processing, is because geometry relation is as shown in Figure 5 set up.Being set to the direction that reaches to stipulate and being benchmark and devices spaced apart d(m) the electric wave angulation of two antenna for receiving 11a, 11b of configuration is θ (rad).Arrive the propagation distance of the electric wave of antenna for receiving 11b, compare long Δ (m) with the propagation distance of the electric wave that arrives antenna for receiving 11a, produce phase delay (phase differential

(rad)).When be illustrated in difference delta and the phase differential of the propagation distance that produces in this model with the wavelength X (m) that receives ripple

Concern the time, become following formula (9) such.In addition, in following formula, Δ＜λ.

[formula 9]

$\mathrm{\&Delta;}=\mathrm{\&lambda;}\&CenterDot;\frac{{\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1}{2\mathrm{\&pi;}}\&CenterDot;\&CenterDot;\&CenterDot;\left(9\right)$

In addition, according to the difference delta of the propagation distance in above-mentioned model, the geometry relation of antenna spacing d, arrival angle θ, following formula (10) is set up.

[formula 10]

Δ＝dsinθ …(10)

That is, arrive angle θ and will be expressed as following formula (11) like that.In addition, formula (11) is suitable with the processing that arrives in angle transformation component 46.So as can be known, can calculate the arrival angle by the arrival angle calculation element of present embodiment.

[formula 11]

$\mathrm{\&theta;}={\sin }^{-1}\frac{{\mathrm{\&phi;}}_2-{\mathrm{\&phi;}}_1}{2\mathrm{\&pi;}}\&CenterDot;\frac{\mathrm{\&lambda;}}{d}\&CenterDot;\&CenterDot;\&CenterDot;\left(11\right)$

Then, to having used the example that arrives the position detecting system of angle calculation element to describe.Position detecting system 101 shown in Figure 6 constitute comprise arrive angle calculation device 1a, with arrive angle calculation element 1a separate predetermined distance D and configure other arrive angle calculation element 1b, access point 2 or user terminal 3.Access point 2 and user terminal 3 constitute, and possess respectively transmitting system and receiving system (not shown), can carry out two-way communication (communication).In addition, access point 2 and user terminal 3 constitute, and can send to arriving angle calculation element 1a and arriving angle calculation element 1b the electric wave that the arrival angle calculation is used by the transmitting system that possesses separately.The object of position probing is that any of access point 2 or user terminal 3 all can.

Arrive angle calculation element 1a and receive the electric wave that sends with antenna from the transmission of access point 2 by antenna for receiving 11aa and 11ab, thereby calculate to arrive angle calculation element 1a as the arrival angle of benchmark.In addition, arrive angle calculation element 1b and receive the electric wave that sends with antenna from the transmission of access point 2 by antenna for receiving 11ba and 11bb, thereby calculate to arrive angle calculation element 1b as the arrival angle of benchmark.If it is known to arrive the position relationship of angle calculation element 1a and arrival angle calculation element 1b, can be according to decide the position of access point 2 with the arrival angle of the benchmark of respectively doing for oneself.

In addition, in the situation that the position probing of user terminal 3 arrives angle calculation element 1a and arrives angle calculation element 1b and calculates from the arrival angle of the electric wave of user terminal 3 transmissions.

Fig. 7 is the process flow diagram of the arrival angle calculation in the arrival angle calculation element 1 that relates to of present embodiment.When arriving the electric wave of angle calculation element 1 reception arrival angle calculation object, acceptance division 12a, 12b receive signal to correlation processing unit 21a, 21b output.After this, correlation processing unit 21a, 21b receive relevant treatment and the addition process of signal in step 201.

After this, peak value test section 22a, 22b detect the peak value P of electric power according to the output signal of correlation processing unit 21a, 21b in step 202 _PeakAfter this, calculate near peak point during electric power sum ∑ P in (between the peak period) ₁And the electric power sum ∑ P during beyond (information unit during) removed between the peak period during 1 ₂, and calculate their ratio R(=∑ P ₁/ ∑ P ₂).Fig. 8 (a) schematically represents to the signal of peak value test section 22a, 22b input.Peak value electric power P _PeakBe the electric power on the peak point P in Fig. 8 (a), ∑ P ₁Be t between the peak period ₁In the electric power sum, ∑ P ₂For removed t between the peak period during 1 ₁During t ₂In the electric power sum.Herein, t between the peak period ₁Be comprise peak value the lifting interval during.For example, as shown in Figure 9, in the situation that use DSSS as modulation system, can form the lifting interval of 2 times of the cycle tc of diffuse code.Therefore, can establish this 2tc during be t between the peak period ₁In addition, in Fig. 9, during t2 use 1 during tb and be expressed as tb-2tc.

Figure 10 represents to be taken into to using the AD transducer example of the signal of peak value test section 22a, the 22b input in the situation that receives signal.The transverse axis t of Figure 10 represents the sample coding, and t gets discrete value.In the situation that use DSSS as modulation system, for example, if diffuse code is to be 1 μ s during 11 chips, 1, be 0.091 μ s during 1 chip of diffuse code.If establish the over-sampling of 4 times during AD is transformed to 1 chip, lifting interval extension 1 chip amount, become ips=ip-3, ipe=ip+3.In this case, R is expressed as following formula (12) like that.

[several 12]

$R=\frac{{\mathrm{\&Sigma;}}_{\mathrm{ip}-3}^{\mathrm{ip}+3}{P}_i}{{\mathrm{\&Sigma;}}_{i1}^{i2}{P}_i-{\mathrm{\&Sigma;}}_{\mathrm{ip}-3}^{\mathrm{ip}+3}{P}_i}\&CenterDot;\&CenterDot;\&CenterDot;\left(12\right)$

In step 203, peak value test section 22a, 22b are with the ratio R(=∑ P that calculates ₁/ ∑ P ₂) with the regulation threshold value R _thCompare.Compare R at R _thIn large situation, peak value test section 22a, 22b export the signal of this content to timing control part 23a, 23b.Timing control part 23a compares R when accepting R _thDuring the signal of large content, think that receiving signal exists peak value, and the required signal of calculating that will arrive angle is exported to arriving angle calculating part 24.After this, in step 204, arrive angle calculating part 24 and calculate the arrival angle.On the other hand, be R at R _thIn following situation, peak value test section 22a, 22b export the signal of this content to timing control part 23a, 23b, and timing control part 23a thinks that receiving signal does not exist peak value, and stops to the output that arrives angle calculating part 24.After this, arriving angle calculation element 1 carries out again from the flow process of step 201 beginning.R _thFor being worth arbitrarily.For example, can will be set as R by the value with the degree that has or not of relatively judging peak value of R _th

Like this, by with the index (R) relevant with the peak value that detects and threshold value (R _th) compare to judge and having or not of peak value can judge exactly having or not of peak value.

Herein, merely to the threshold of power (electric power) and power being judged the method that has or not of peak value investigates.Fig. 8 (b) schematically represents the high signal of background value (solid line) and the low signal (dotted line) of background value.In Fig. 8 (b), in the situation that such background value shown in dotted line is low, can pass through the peak value of power and the threshold value P of power _thCompare, come detection peak.But, in Fig. 8 (b), arrive over P when background value as shown in solid line is high _thDegree the time, even with peak value and the P of power _thComparing can not detection peak.This be because, the threshold value of the peak value of power and power simple relatively in, can not consider background value.So, as shown in present embodiment, by use the index of having considered background value in the detection of peak value, can judge exactly having or not of peak value.

Such as shown above, the arrival angle calculation element that present embodiment relates to, by obtain between the peak period electric power and between the peak period beyond remaining during in electric power ratio, and relatively this ratio of obtaining and threshold value judge having or not of peak value, even in the situation that receive the high calculating that also can detect exactly the peak value of expectation ripple and be used for the arrival angle of the background value of ripple.That is, do not calculate the arrival angle according to the component of signal beyond the expectation ripple, therefore can improve the computational accuracy that arrives angle.

Figure 11 is the block diagram that explanation arrives another form of the arrival angle calculating part 24 in angle calculation element 1.Arrival angle calculating part 24 shown in Figure 11 possesses: the output O that gets timing control part 23a _a1Complex conjugate complex conjugate section 51; Output O with complex conjugate section 51 _{A1 '}Output O with timing control part 23b _a2The complex multiplication section 52 of complex multiplication; And the arc tangent section 53 that carries out arctangent cp cp operation with the output of complex multiplication section 52.Action, the function of complex conjugate section 51, complex multiplication section 52, arc tangent section 53, same with action, the function of above-mentioned complex conjugate section 41, complex multiplication section 42, arc tangent section 43.Possess in addition: the phase difference correction section 54 that comes the correction calculation result based on the operation result (phase differential) of arc tangent section 53; Equalization section 55 with the output equalization of phase difference correction section 54; In the situation that carried out proofreading and correct the phase differential correction unit 56 again of the operation result (mean value) of equalization section 55 in phase difference correction section 54; And use phase differential again correction unit 56 output and be transformed to the arrival angle transformation component 57 that arrives angle.Arrive action, the function of angle transformation component 57, same with action, the function of above-mentioned arrival angle transformation component 46.

Phase difference correction section 54, in the situation that as the phase differential of the operation result of arc tangent section 53 become+180 ° (+π) near ,-180 ° (the value π) carries out adding the processing of the angle (phase differential) of regulation in the operation result of arc tangent section.As shown in the I-Q plane of Figure 12, the arrival angle calculating part 24 of present embodiment phase differential is projected to-180 °～+ 180 ° (π～+ coordinate of π) phase range on.Therefore, for example, as shown in Figure 13 (a), in the situation that the phase differential that is calculated by arc tangent section 53 do not become+near 180 ° and-180 ° value, by with its equalization, and can suitably calculate the arrival angle.But as shown in Figure 13 (b), in the situation that the phase differential that is calculated by arc tangent section 53 becomes+near 180 and-180 value, a little error of the phase differential that calculates will apply large impact to angle calculation., be assumed to two values that obtain-178 ° and+178 ° as phase data herein, as a side value+178 ° of-178 ° of being based on as original value become after producing the error of-4 °+178 °.Their difference is in fact only 4 °.But, in to handle averagely, when conduct-178 ° and+178 ° and during equalization, mean value becomes 0 °.Although in fact there is the approximately phase differential of 180 °, can process as 0 ° by to handle averagely.Like this, when the phase differential of institute's equalization significantly departed from from original phase differential, it is difficult that suitable arrival angle calculation becomes.

So, arrival angle calculating part 24 shown in Figure 11, in the situation that the phase differential that is calculated by arc tangent section 53 becomes+near 180 ° and-180 ° value, phase difference correction section 54 carries out adding that the correction of the angle (phase differential) of regulation processes in the operation result of arc tangent section 53, and carries out suitable equalization.Whether the operation result of arc tangent section 53 is near the value+180 ° or-180 °, can based on as the operation result of arc tangent section 53 and the distribution of a plurality of phase differential that obtain judge.For example, in the situation that greater than+90 ° (+pi/2s) or less than the quantity of the phase differential of-90 ° (pi/2s), than less than+90 ° and Duo greater than the quantity of the phase differential of-90 °, the operation result that can be judged to be arc tangent section 53 is near the value+180 ° and-180 °.Can make the angle (phase differential) that phase difference correction section 54 adds for example be+90 °, but so long as can carry out the angle of suitable to handle averagely, be not to be defined in this.Preferably, also can for-90 ° ,+any of 180 ° or-180 °.

Equalization section 55 is with the output equalization of phase difference correction section 54.Therefore the arrival angle calculating part 24 of present embodiment in the situation that calculating is unsuitable for the correction that the phase differential of equalization adds phase differential, can carry out suitable to handle averagely in equalization section 55.Phase differential is correction unit 56 again, in the situation that carried out the correction of phase differential in phase difference correction section 54, proofreaies and correct the output of equalization section 55.Particularly, deduct the correction of the angle (phase differential) that has added as corrected value in phase difference correction section 54.

Figure 14 represents that schematically phase differential becomes+summary of arrival angle calculation near 180 ° and-180 ° situation.In the situation that near be+180 ° and-180 ° in the I-Q plane, phase difference correction section 54 adds corrected value (+90 °) and coordinate axis is rotated, and is transformed to the coordinate axis that mean value calculation is used in phase differential at the phase differential that is calculated by arc tangent section 53.Equalization section 55 comes calculating mean value (92 °) based on these data.Phase differential correction unit 56 again carries out deducting from the output data of phase difference correction section 54 correction of corrected value (+90 °), and the data (+178 °) after proofreading and correct to 57 outputs of inverse sine section.

Figure 15 is the processing flow chart in above-mentioned arrival angle calculating part 24.The output O of timing control part 23a calculates in the complex conjugate section 51 that arrives angle calculating part 24 in step 301 _a1Complex conjugate.In addition, complex multiplication section 52 in step 302 with the output O of timing control part 23b _a2Output O with complex conjugate section 51 _{A1 '}Multiply each other.After this, arc tangent section 53 carries out arctangent cp cp operation with the output of complex multiplication section 52 in step 303, calculate the phase differential that receives between signal.

In step 304, near the phase differential that the calculates value whether as+180 ° and-180 ° in the I-Q plane is judged by phase difference correction section 54.In the situation that the phase differential that calculates not is+near 180 ° and-180 ° value, enter step 305, phase calibration is poor and calculate and arrive angle to arrive angle calculating part 24.In the situation that the phase differential that calculates enters step 306 near+180 ° or near the value-180 °.This judgement, as described above, can with greater than+90 ° or less than the quantity of the phase differential of-90 ° whether than less than+90 ° and mostly be benchmark greater than the quantity of the phase differential of-90 ° and carry out.

In step 306, phase difference correction section 54 carries out adding the processing of 90 ° in the phase differential as the operation result of arc tangent section 53.In step 307, equalization section 55 is with the output equalization of phase difference correction section 54.After this, in step 308, phase differential correction unit 56 again carries out deducting the processing of 90 ° from the mean value as the operation result of equalization section 55.After this, in step 309, arrive angle transformation component 57 according to phase differential again the output of correction unit 56 calculate the arrival angle.Like this, in arrival angle calculating part 24 shown in Figure 11, suitable mean value is calculated in a series of processing of the phase differential by deducting regulation after the phase differential that adds regulation and equalization, and the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

In addition, herein, phase difference correction section 54 carries out adding the processing of the angle of regulation in the operation result of arc tangent section 53, as long as but can realize suitable to handle averagely, be not to be defined in this.For example, also can use the arrival angle calculating part 24 of formation as shown in Figure 16.Arrival angle calculating part 24 shown in Figure 16 possesses: the output O that gets timing control part 23a _a1Complex conjugate complex conjugate section 61; And with the output O of complex conjugate section 61 _{A1 '}Output O with timing control part 23b _a2The complex multiplication section 62 of complex multiplication.Action, the function of complex conjugate section 61, complex multiplication section 62, same with action, the function of above-mentioned complex conjugate section 41, complex multiplication section 42.Possess in addition: the IQ comparing section 63 that the absolute value of the in-phase component (I component) of the output of complex multiplication section 62 is compared with the absolute value of quadrature component (Q component); And the output of using complex multiplication section 62, select, change operational method according to the output of IQ comparing section 63, and carry out the arc tangent section 64 of arctangent cp cp operation.Possess in addition: will be as the equalization section 65 of the phase differential equalization of the operation result of arc tangent section 64; Proofread and correct as the phase differential of the mean value of the operation result of equalization section 65 correction unit 66 again according to the operational method of arc tangent section 64; And use phase differential again correction unit 66 output and be transformed to the arrival angle transformation component 67 that arrives angle.Arrive action, the function of angle transformation component 67, same with action, the function of above-mentioned arrival angle transformation component 46.

Whether IQ comparing section 63 judges the in-phase component (I component) of output of complex multiplication section as negative, and the relatively absolute value of the in-phase component (I component) of the output of complex multiplication section 62 and the absolute value of quadrature component (Q component).Particularly, IQ comparing section 63 is judged the symbol of in-phase component Ib, and judges the absolute value ︱ Ib ︱ of in-phase component compares whether abundant (whether fully little the absolute value ︱ Qb ︱ of quadrature component compares with the absolute value ︱ Ib ︱ of in-phase component) greatly with the absolute value ︱ Qb ︱ of quadrature component.At the phase differential that receives signal in the situation that get in the I-Q plane+near 180 ° and-180 ° value, in-phase component Ib is negative (Ib＜0), the absolute value ︱ Ib ︱ of in-phase component compares fully large with the absolute value ︱ Qb ︱ of quadrature component.Therefore, whether the symbol by judging in-phase component Ib and the absolute value ︱ Ib ︱ that judges in-phase component compare fully large with the absolute value ︱ Qb ︱ of quadrature component, can judge whether phase differential is got+near 180 ° and-180 ° value.

Arc tangent section 64 uses the output of complex multiplication section 62, comes the Selecting operation method to carry out arctangent cp cp operation according to the output of IQ comparing section 63.In the situation that in-phase component is positive, in-phase component for the absolute value ︱ Qb ︱ of the absolute value ︱ Ib ︱ of negative and in-phase component and quadrature component is same degree or little than it, carry out output Ib take complex multiplication section 62 as denominator, to export Qb as the arctangent cp cp operation of the value of molecule.In the situation that in-phase component is compared fully large for the absolute value ︱ Ib ︱ of negative and in-phase component with the absolute value ︱ Qb ︱ of quadrature component, for example, carry out so that the sign-inverted of the output Qb of complex multiplication section 62-Qb is denominator, the arctangent cp cp operation take output Ib as the value of molecule.In addition, in the situation that the absolute value ︱ Ib ︱ of in-phase component compares fully large above-mentioned processing with the absolute value ︱ Qb ︱ of quadrature component, the processing of carrying out arctangent cp cp operation with making+90 ° of coordinate axis rotations is suitable.That is the phase differential that, obtained by this processing is for having added in original phase differential+value of 90 °.

In addition, in the situation that the absolute value ︱ Ib ︱ of in-phase component compares fully large processing with the absolute value ︱ Qb ︱ of quadrature component, be not to be defined in above-mentioned processing.For example, also can carry out output Qb take complex multiplication section 62 as denominator so that the sign-inverted of output Ib-Ib is the arctangent cp cp operation of the value of molecule.This is processed, and the processing of carrying out arctangent cp cp operation with making-90 ° of coordinate axis rotations is suitable.That is the phase differential that, obtained by this processing is for having added the value value of 90 ° (deducted+) of-90 ° in original phase differential.In addition, for example also can make the sign-inverted of the symbol of output Ib of complex multiplication section 62 and output Qb and carry out arctangent cp cp operation.This processing, the processing of carrying out arctangent cp cp operation with making coordinate axis rotation+180 ° (or-180 °) is suitable.That is the phase differential that, obtained by this processing is for having added in original phase differential+value of 180 ° (or-180 °).By this processing, also can calculate suitable mean value.

Equalization section 65 is with the output equalization of arc tangent section 64.The arrival angle calculating part 24 of present embodiment is in the situation that calculating is unsuitable for the correction that the phase differential of equalization adds in fact (or deducting) phase differential, therefore can carry out suitable to handle averagely in equalization section 65.Phase differential correction unit 66 again in the situation that arc tangent section 64 has carried out making the processing of+90 ° of coordinate axis rotations, is proofreaied and correct the output of equalization section 65.Particularly, deduct+correction of 90 °.In addition, in the situation that arc tangent section 64 has carried out making the processing of-90 ° of coordinate axis rotations, deduct the correction correction of 90 ° (namely add+) of-90 °.Equally, in the situation that arc tangent section 64 has carried out making the processing of coordinate axis rotation+180 ° (or-180 °), deduct+180 ° the correction of (or-180 °).

Like this, arrival angle calculating part 24 shown in Figure 16 also can similarly calculate suitable mean value with arrival angle calculating part 24 shown in Figure 11, and the computational accuracy that therefore arrives angle does not just reduce.As a result, can fully improve the computational accuracy that arrives angle.

Figure 17 means the block diagram of the concrete configuration example of the arrival angle calculation element in the situation of using OFDM (OFDM) as modulation system.In addition, in Figure 17, only show with Fig. 1 in the suitable formation of operational part 13.

In Figure 17, correlation processing unit 21a possesses: the complex conjugate complex conjugate 71a of section that gets the output of acceptance division 12a; Make the amount of output delay specified time limit of acceptance division 12a and the delay 72a of section of output; The complex multiplication 73a of section with the output complex multiplication of the output of the complex conjugate 71a of section and the delay 72a of section; And only at GI(protection interval) during the output of the addition complex multiplication 73a of section and totalizer 74a, the 74b of output.Peak value test section 22a possesses: calculating is from the power system calculation 75a of section of the electric power of the signal of totalizer 74a, 74b output; And the peak value electric power test section 76a that detects its electric power peak value and export to timing control part 23a.Timing control part 23a possesses based on controlling from the signal of peak value electric power test section 76a from the signal of acceptance division 12a to the output that the arrives angle calculating part 24 delay 77a of section regularly.Equally, correlation processing unit 21b possesses the complex conjugate 71b of section, the delay 72b of section, the complex multiplication 73b of section, totalizer 74c, 74d, and peak value test section 22b possesses the power system calculation 75b of section, peak value electric power test section 76b, and timing control part 23b possesses the delay 77b of section.Arriving angle calculating part 24 possesses: the complex conjugate complex conjugate section 81 of getting the output of the delay 77a of section; Complex multiplication section 82 with the output complex multiplication of the output of complex conjugate section 81 and the delay 77b of section; Only at GI(protection interval) during the output of addition complex multiplication section 42 and adder 83a, the 83b of output; Carry out the arc tangent section 84 of arctangent cp cp operation with the output of adder 83a, 83b; Equalization section 85 with the output equalization of arc tangent section 84; And be transformed to the output of equalization section 85 the arrival angle transformation component 86 that arrives angle.

Therefore the 72a of delay section, 72b get the auto-correlation of OFDM symbol string, make amount and the output of output delay specified time limit of acceptance division 12a.Particularly; the 72a of delay section, 72b; for with the afterbody of the OFDM symbol of the complex conjugate 71a of section output and the GI(protection interval of the delay 72a of section, 72b output) input to the complex multiplication 73a of section in identical timing, and make amount and the output of output delay specified time limit of acceptance division 12a.The 73a of complex multiplication section is with the output of the complex conjugate 71a of section and the output complex multiplication of the delay 72a of section.Only output and the output of each chip interval of the addition complex multiplication 73a of section during GI of totalizer 74a and 74b.

Figure 18 (a) means the schematic diagram of the formation of OFDM symbol string.As shown in Figure 18 (a), the OFDM symbol string is made of with the initial GI that is configured in the OFDM symbol the OFDM symbol as data portion.GI is the data that copied OFDM symbol afterbody, is inserted in order to prevent the intersymbol interference of OFDM.Figure 18 (b) means the schematic diagram of situation of the relevant treatment (auto-correlation processing) of the OFDM symbol string in correlation processing unit 21a.As shown in Figure 18 (a), the output delay of the relative complex conjugate 71a of section of the output of the delay 72a of section the amount of OFDM symbol lengths.Therefore, in the complex multiplication 73a of section, can take from relevant by the output of the complex conjugate 71a of section and the output multiplication of the delay 72a of section.Autocorrelation value (GI correlation) illustrates peak value when the data identical with GI occurring in the output of the output of the complex conjugate 71a of section and the delay 72a of section, therefore by the use this point, and can detect initial as the OFDM symbol of data portion.

The output signal of totalizer 74a and 74b is transfused to the power system calculation 75a of section of peak value test section 22a.The 75a of power system calculation section calculates the electric power of each chip interval according to the output signal of totalizer 74a and 74b.Particularly, the absolute value addition of the absolute value of the output signal that the power system calculation 34a of section will be suitable with in-phase component and the output signal suitable with quadrature component is as the power information of each chip interval and export to peak value electric power test section 76a.In addition, also the square value phase adduction of the square value of the output signal suitable with in-phase component and the output signal suitable with quadrature component can be exported to peak value electric power test section 76a.Figure 19 (a) expression is from the example of the output waveform of the power system calculation 75a of section.Figure 19 (b) is the part enlarged drawing of the output waveform shown in Figure 19 (a).Peak value electric power test section 76a detect to receive the electric power peak value in signal when accepting the power information of each chip interval, as the electric power peak information and to the delay 77a of the section output of timing control part 23a.

From peak value test section 22a(peak value electric power test section 35a) the electric power peak information of output is the information that has or not of the peak value that judge to receive signal.Particularly, the electric power peak information is, expression receive near the peak point of signal during electric power sum ∑ P in (between the peak period) ₁And the electric power sum ∑ P in during beyond having removed between the peak period during 1 symbol of the information unit from become OFDM ₂Ratio R(=∑ P ₁/ ∑ P ₂) whether greater than threshold value R _thLarge information.In the situation that use OFDM as modulation system, equate between the peak period with during GI.In addition, during so-called 1 symbol, with added up to during GI and data during (during the OFDM symbol) during quite.In the electric power peak information, at R greater than R _thSituation under, the timing control part 23a(delay 77a of section) think that regularly receiving signal at this has peak value, and will be from the reception signal of acceptance division 12a to arriving angle calculating part 24.On the other hand, at R less than R _thSituation under, the timing control part 23a(delay 77a of section) think that regularly receiving signal at this does not have peak value, and stop to the output that arrives angle calculating part 24.In addition, herein, peak value test section 22a has carried out the calculation process relevant with the electric power peak information, but also can carry out the calculation process relevant with the electric power peak information in timing control part 23a.

The correlation processing unit 21b(complex conjugate 71b of section, the delay 72b of section, the complex multiplication 73b of section, totalizer 74c, 74d), the peak value test section 22b(power system calculation 75b of section, peak value electric power test section 76b), the timing control part 23b(delay 77b of section) action, function, with the correlation processing unit 21a(complex conjugate 71a of section, the delay 72a of section, the complex multiplication 73a of section, totalizer 74a, 74b), the peak value test section 22a(power system calculation 75a of section, peak value electric power test section 76a), the timing control part 23a(delay 77a of section) action, function same.Just, to the reception signal of correlation processing unit 21b input with to the reception signal of correlation processing unit 21a input, owing to having received identical electric wave at 2 that separate predetermined distance, so phase place is slightly different.Therefore, with from the signal of timing control part 23a output, phase place is slightly different at the signal of exporting from timing control part 23b.

The output of timing control part 23a is transfused to the complex conjugate section 81 that arrives angle calculation section 24.Complex conjugate section 81 with the complex conjugate of the output of timing control part 23a to 82 outputs of complex multiplication section.Complex multiplication section 82 is the output of complex conjugate section 81 and the output complex multiplication of timing control part 23b, and with operation result to adder 83a and 83b output.The output of adder 83a and 83b each chip interval of addition complex multiplication section 82 during GI and to 84 outputs of arc tangent section.Figure 19 (c) expression is from the example of the output waveform of adder 83a and 83b.In the drawings, the output waveform of adder 83a represents by I, and the output waveform of adder 83b is represented by Q.

Arctangent cp cp operation is carried out in the output of the 84 use adder 83a of arc tangent section and 83b, calculates the phase differential that receives signal.Figure 19 (d) expression is from the example of the output waveform of arc tangent section 84.Equalization section 85 is with the output equalization of arc tangent section 84 and to arriving 86 outputs of angle transformation component.In addition, equalization section 85 also can suitably omit.Arrive the output that angle transformation component 86 uses equalization section 85 (in the situation that do not have equalization section 85, the output of arc tangent section 84) and be transformed to the arrival angle by the inverse trigonometric function computing.Suitable with the arrival angle by value, the output that namely arrives angle transformation component 86 that this computing is obtained.

Like this, in the arrival angle calculation element 1 of the operational part 13 with Figure 17, also by obtain between the peak period electric power and between the peak period beyond remaining during in electric power ratio, and relatively this ratio of obtaining and threshold value judge having or not of peak value, even in the situation that receive the high calculating that also can detect exactly the peak value of expectation ripple and be used for the arrival angle of the background value of ripple.That is, do not calculate the arrival angle according to the component of signal beyond the expectation ripple, therefore can improve the computational accuracy that arrives angle.

Figure 20 means the schematic diagram that arrival angle calculation element 1 is applied to the location-specific capsule endoscope system of capsule endoscope.Capsule endoscope system shown in Figure 20 possesses a plurality of sensor arraies 401, records the data recorder 402 from the data of sensor array 401.Sensor array 401 possesses the antenna suitable with the antenna for receiving that arrives angle calculation element 1, and constitutes the electric wave that can receive the capsule endoscope of swallowing from the patient.The phase information that data recorder 402 has according to the electric wave that receives in sensor array 401 is determined the position of the capsule endoscope that the patient swallows.

The capsule endoscope that the patient swallows moves by gastral vermicular movement.The position of capsule endoscope is monitored, and can be confirmed whether to have arrived the examination position.When capsule endoscope arrives the examination position, capsule endoscope will be examined the situation photography at position and send data recorder 402 recording image informations to data recorder 402.Like this, by the position of supervision capsule endoscope, and over sight (OS) is not examined the position and is photographed.In addition, the power supply of camera etc. can be connected in the timing that capsule endoscope has arrived the examination position, and in the situation that broken away from the power supply that the examination position cuts off camera etc., therefore battery capacity can be reduced.In addition, can cut down the quantity of sensor (antenna).In addition, if battery capacity is identical, compares with the capsule endoscope of type in the past and can send a large amount of images, can obtain distinct image.

Like this, be applied to the location positioning of capsule endoscope by arriving angle calculation element 1, can construct good capsule endoscope system.

As described above, according to arrival angle calculation element of the present invention, obtain between the peak period electric power and between the peak period beyond remaining during in the ratio of electric power, and this ratio and threshold value of obtaining relatively, in the situation that arrive angle than calculating greater than threshold value, even therefore in the situation that the signal level beyond the expectation ripple of reception ripple is high, also can detect exactly the peak value of expectation ripple, and calculating arrives angle.That is, do not calculate according to the part beyond the expectation ripple and arrive angle, therefore can improve the computational accuracy that arrives angle.

In addition, the present invention is not the record that is defined in above-mentioned embodiment, can suitably change in the mode of bringing into play its effect.For example, in the above-described embodiment, ratio and the threshold of the electric power sum during with the electric power sum between the peak period and except between the peak period, as long as but can consider the arrival angle calculation of the level of the signal beyond the expectation ripple, be not limited thereto.For example, also can use between the peak period certain regularly electric power and except between the peak period during electric power of certain timing as parameter.

In addition, in the above-described embodiment, formation shown in the drawings etc. are not to be defined in this, can suitably change in the scope of performance effect of the present invention.

Utilizability on industry

Arrival angle calculation element of the present invention can be used for be determined system, and other various uses of the position of object.

The application is based on the Japanese Patent Application that proposed on November 12nd, 2010 No. 2010-254011, and has comprised its full content.

Claims (9)

1. one kind arrives the angle calculation element, it is characterized in that,

Possess: a plurality of antennas receive the electric wave that sends from certain position; A plurality of reception signal processing parts arrange accordingly with described each antenna; And arrive the angle calculating part, thus be taken into from the output signal by described a plurality of reception signal processing part outputs the arrival angle that the component of signal that becomes identical information unit between the reception signal processing part is calculated described electric wave,

The described signal processing part that respectively receives possesses: acceptance division, will by the described antenna reception of correspondence to electric wave be transformed to reception signal and the output of the phase information with this electric wave; Correlation processing unit will be carried out relevant treatment from the reception signal of described acceptance division output; The peak value test section, the peak value of the reception signal of described relevant treatment has been carried out in detection; And timing control part, cut out the mode that becomes the component of signal of identical information unit between described reception signal processing part with the output signal from described correlation processing unit, match with the timing of the peak value that is detected by described peak value test section, thereby control being taken into regularly from the output signal of described correlation processing unit output

In the situation that the electric power between the peak period in during suitable with described information unit and except between this peak period during the ratio of electric power greater than threshold value, described timing control part will be exported to described arrival angle calculating part from the signal of described correlation processing unit.

2. arrival angle calculation element as claimed in claim 1, is characterized in that,

With ∑ P ₁With ∑ P ₂Than ∑ P ₁/ ∑ P ₂Compare with threshold value, described than ∑ P ₁/ ∑ P ₂In situation greater than described threshold value, described timing control part will be exported to described arrival angle calculating part from the signal of described correlation processing unit, wherein above-mentioned ∑ P ₁Electric power sum between the peak period in during suitable with described information unit, above-mentioned ∑ P ₂Electric power sum in during in during suitable with described information unit except between the described peak period.

3. arrival angle calculation element as claimed in claim 1 or 2, is characterized in that,

Described arrival angle calculating part possesses:

Complex conjugate section fetches the complex conjugate of signal of timing control part of the reception signal processing part of My World, and this side's reception signal processing part is corresponding with a side antenna;

Complex multiplication section, with the output of described complex conjugate section with from the signal multiplication of the timing control part of the opposing party's reception signal processing part, this opposing party's reception signal processing part is corresponding with the opposing party's antenna;

Arc tangent section carries out arctangent cp cp operation with the output of described complex multiplication section, calculates the phase differential of the described reception electric wave between described antenna;

Equalization section averages the output of described arc tangent section; And

Arrive the angle transformation component, carry out the inverse trigonometric function computing with the output of described equalization section, thereby be transformed to the arrival angle.

4. arrival angle calculation element as claimed in claim 3, is characterized in that,

The described phase differential that calculates distribute in the situation that on the I-Q plane+180 ° and/or-180 ° near, described arrival angle calculating part averages after making each phase differential rotation predetermined angular, carry out the inverse trigonometric function computing after this mean value deducts described predetermined angular, thereby be transformed to the arrival angle.

5. arrival angle calculation element as claimed in claim 4, is characterized in that,

On described I-Q plane, in the situation that greater than+90 ° or less than the quantity of the phase differential of-90 ° than less than+90 ° and Duo greater than the quantity of the phase differential of-90 °, be judged as be distributed on described I-Q plane+180 ° and/or-180 ° near.

6. arrival angle calculation element as described in claim 4 or 5, is characterized in that,

Described predetermined angular be+90 ° ,-90 ° ,+any angles of 180 ° or-180 °.

7. arrival angle calculation element as claimed in claim 3, is characterized in that,

In the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by changed the arctangent cp cp operation of the relation of I component and Q component after the symbol of described Q component that reversed, come the phase differential after calculation correction, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value deducts 90 °, thereby be transformed to the arrival angle.

8. arrival angle calculation element as claimed in claim 3, is characterized in that,

In the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by changed the arctangent cp cp operation of the relation of I component and Q component after the symbol of described I component that reversed, come the phase differential after calculation correction, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value is added 90 °, thereby be transformed to the arrival angle.

9. arrival angle calculation element as claimed in claim 3, is characterized in that,

In the situation that the I component of the output of described complex multiplication section is compared fully large for the absolute value of the I component of the output of negative and described complex multiplication section with the absolute value of Q component, by carry out the phase differential after arctangent cp cp operation is come calculation correction after the symbol of the symbol of the described I component that reversed and Q component, phase differential after described correction is averaged, carry out the inverse trigonometric function computing after this mean value deducts 180 °, thereby be transformed to the arrival angle.

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