JP5126527B2 - Positioning signal tracking processing device and positioning device - Google Patents

Description

  The present invention relates to a device for tracking a carrier frequency and a code of a positioning signal in order to demodulate the positioning signal.

  Conventionally, in a GNSS receiver such as a GPS receiver, it is necessary to measure a pseudorange or a Doppler frequency in order to perform positioning or the like. In order to measure the pseudorange and the Doppler frequency, it is necessary to perform acquisition (search) and tracking of the positioning signal. In particular, in order to measure the pseudorange and Doppler frequency with high accuracy, both code tracking and carrier frequency tracking must be performed.

  However, in such a GNSS receiver, depending on the state at the time of acquisition of the positioning signal, in the process where the carrier frequency is driven and locked after entering the tracking state, sufficient tracking cannot be performed or the wrong carrier frequency is locked. An abnormal tracking phenomenon occurs. For example, abnormal tracking as shown in FIG. 6 may occur.

  FIGS. 6A and 6B are simulation results of the carrier frequency transition state and the C / No (carrier power to noise power density ratio) transition state when the abnormal tracking related to the C / A code of the GPS L1 wave occurs. FIGS. 6C and 6D are diagrams showing the carrier frequency transition situation and the C / No transition situation simulation result when the abnormal tracking related to the I code of the L5 wave of GPS occurs.

  6 (A) and 6 (B), the L1 wave C / A code can be ideally tracked with a carrier frequency of 0 [Hz] and a target frequency of 500 [Hz] after baseband conversion at the time of acquisition. The case where C / No at the time is 50 [dB-Hz] is shown. When tracking is started in such a condition, that is, in a state where there is a frequency deviation of 550 Hz with respect to the target frequency, the carrier frequency estimated by this tracking is −1000 [Hz], that is, the frequency deviation is about 1.5 [ kHz], and C / No remains low. For this reason, steady tracking cannot be achieved.

  6 (C) and 6 (D), when the carrier frequency after the baseband conversion at the time of acquisition is 0 [Hz] and the target frequency is 500 [Hz] with respect to the L5 wave I code, tracking can be performed ideally. This shows a case where the C / No is 50 [dB-Hz]. When tracking is started under such conditions, that is, with a frequency deviation of 300 Hz with respect to the target frequency, the carrier frequency estimated by this tracking is −200 [Hz], that is, the frequency deviation is 500 [Hz]. Therefore, C / No is a high value. As a result, the tracking is performed while being locked at the wrong carrier frequency.

As a method for solving such a problem, code search is performed after search, and after confirming that the code phase difference is sufficiently small, the code phase difference such as a predetermined time length (for example, 1 second) is set. A method of observing, estimating an initial value of the carrier frequency from the least square value of the code phase difference, and tracking the carrier frequency from the initial value is considered. Furthermore, Patent Document 1 uses a plurality of channels for one positioning satellite (positioning signal), performs peak search, sidelobe check corresponding to the peak, and carrier frequency confirmation of the peak value, thereby ensuring accurate A method of narrowing down the carrier frequency is also considered.
JP 2004-12378 A

  However, in the case of the method using the least square method described above, one channel may be allocated to one positioning satellite (positioning signal). However, since the least square method is used, the calculation processing amount increases and the processing load increases. Becomes larger. Also, since the sampling time for performing the least square method is constant regardless of C / No, processing for performing high-precision code tracking and carrier frequency tracking can be flexibly performed according to C / No, that is, the reception environment. There is a possibility that high-accuracy tracking cannot be performed depending on C / No.

  Moreover, since the method as shown in Patent Document 1 requires two channels for one positioning satellite (positioning signal), a lot of resources are required.

  In view of such problems, the object of the present invention is to suppress the influence on the code tracking result and carrier frequency tracking result by C / No, and a positioning signal with a simple configuration capable of high-accuracy code and carrier frequency tracking. This is to realize a tracking processing device.

  The present invention relates to a positioning signal tracking processing device including a carrier tracking unit that tracks a carrier frequency based on a positioning signal and a code tracking unit that tracks a code based on a positioning signal. This positioning signal tracking processing device includes C / No estimation means, carrier frequency estimation means, and estimation time determination means. The C / No estimation means estimates the C / No of the positioning signal that has been subjected to predetermined correlation processing. The carrier frequency estimation means is provided in the code tracking unit, and estimates the carrier frequency over a predetermined time based on the code Doppler component detected by the code tracking unit. The estimation time determining means determines a predetermined time for estimating the carrier frequency based on C / No. The carrier tracking unit tracks the carrier frequency using the carrier frequency estimated by the carrier frequency estimating means as an initial value.

  In this configuration, in the code tracking unit, the carrier frequency is continuously estimated from the code Doppler component by the carrier frequency estimation means together with the code tracking process. The tracked code is sequentially used for correlation processing with the positioning signal, and the C / No estimation means sequentially estimates the C / No of the signal after the correlation processing. The estimation time determination means determines the carrier frequency estimation time in the carrier frequency estimation means based on C / No. When the estimated estimation time is reached, the carrier frequency estimated by the carrier frequency estimation means is given as an initial value to the carrier tracking unit, and carrier tracking is executed. As a result, the carrier frequency improved in accuracy by the code tracking unit is input to the carrier tracking unit as an initial value.

  Further, the estimated time determining means of the positioning signal tracking processing apparatus of the present invention shortens the predetermined time for estimating the carrier frequency as the C / No is improved.

  In this configuration, if the C / No is originally good, that is, if the reception environment is good, the carrier frequency is estimated earlier. Also, even if the C / No is bad at the beginning of code tracking, the estimation time of the carrier frequency becomes shorter as the code is matched and the C / No is improved. Thereby, the optimal estimated time is determined according to the situation of C / No.

  Moreover, the estimated time determination means of the positioning signal tracking processing device of the present invention sets a transition time that becomes shorter as the C / No becomes better. Then, the estimated time determining means integrates the reciprocal of the transition time at each preset timing, and sets the time until the integrated value reaches a predetermined value as the predetermined time for estimating the carrier frequency.

  In this configuration, the estimated time of the carrier frequency is determined only by the integration process of the reciprocal of the transition time based on C / No. Thereby, the estimation time of the carrier frequency which changes with the transition of C / No is determined by a simple process.

  Further, the estimated time determining means of the positioning signal tracking processing device of the present invention integrates C / No at every preset timing, and estimates the carrier frequency for the time until the integrated value reaches a predetermined value. It is a predetermined time.

  In this configuration, the estimated time of the carrier frequency is calculated without using the transition time by using the integrated value of C / No as the criterion for determining the estimated time.

  Further, the code tracking unit of the positioning signal tracking processing device of the present invention includes a code phase difference detection unit. The code phase difference detection unit detects a code phase difference between the code superimposed on the positioning signal and the replica code generated by the code NCO. On the output side of the code phase difference detection unit of the positioning signal tracking processing device, a first system and a second system having amplifiers having different gains are provided, and the second system includes a code The integrator for integrating the code Doppler component of the phase over a predetermined time is inserted. In such a configuration, specifically, the carrier frequency estimation means includes a code phase difference detection unit, a second system amplifier, and a second system integrator. The carrier tracking unit tracks the carrier frequency using the carrier frequency based on the value output from the accumulator as an initial value.

  In this configuration, a specific configuration of the above-described carrier frequency estimation means is shown. With this configuration, the carrier frequency estimation means includes a code phase difference detection unit essential for the code tracking unit and a feedback for code tracking. It is composed of an amplifier and an integrator generally installed in the loop. In particular, since amplifiers and integrators are general circuits, the carrier frequency estimation means is realized with a general-purpose simple circuit configuration.

  The positioning device of the present invention includes a demodulation unit, a navigation message acquisition unit, and a positioning unit. The demodulator includes the positioning signal tracking processing device described above, and calculates the pseudo distance based on the code phase difference of the code being tracked and the carrier frequency. The navigation message acquisition unit acquires a navigation message from the positioning signal demodulated by the demodulation unit. The positioning unit performs a positioning calculation using the pseudo distance and the navigation message.

  In this configuration, since the code and the carrier frequency are tracked reliably and with high accuracy as described above, the pseudorange can be acquired with high accuracy. Thereby, highly accurate positioning calculation becomes possible.

  According to the present invention, it is possible to reliably and highly accurately code without affecting the tracking accuracy due to C / No with a simple configuration and a simple calculation process without performing a complicated and large calculation amount process. Tracking and carrier frequency tracking can be performed.

  A configuration of a positioning signal tracking processing device according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the case of GPS will be described as an example, but the following configuration can also be applied to a positioning signal tracking processing device in another system of GNSS such as Galileo.

  FIG. 1 is a block diagram showing a schematic configuration of a positioning device including a demodulator having a positioning signal tracking processing device of the present embodiment.

  The positioning device includes a positioning signal receiving antenna 11, a down converter 12, a demodulation unit 13 including a positioning signal tracking processing device of the present invention, a navigation message acquisition unit 14, and a positioning unit 15. The positioning signal receiving antenna 11 receives a positioning radio signal transmitted from a positioning satellite, and outputs a positioning signal obtained by converting an electric signal to the down converter 12. The positioning signal is a signal obtained by spectrum-spreading a carrier wave having a predetermined frequency (for example, 1575.42 MHz for a GPS L1 wave) using a code and a navigation message set for each positioning satellite. The down-converter 12 down-converts the frequency of the positioning signal to generate an intermediate frequency signal (hereinafter referred to as “IF signal”) having a predetermined frequency, and supplies it to the demodulator 13.

  The demodulation unit 13 performs carrier correlation and code correlation on the spread spectrum IF signal, and performs despreading by integrating the signals after the correlation processing over a predetermined time length. Here, if the carrier correlation and the code correlation are performed with high accuracy, only the navigation message is superimposed on the despread signal.

  The demodulator 13 first performs signal acquisition (search) to perform coarse adjustment of the code and the carrier frequency. The demodulator 13 executes a single code tracking loop process that performs only code tracking when C / No exceeds the search threshold. At this time, the demodulator 13 uses the carrier frequency set at the end of the search for carrier correlation and does not perform carrier tracking. Next, when the code matching in the single code tracking loop is successful, the demodulator 13 performs a concatenated code / carrier tracking loop process (for phase-synchronized DLL processing) that performs code tracking and carrier tracking simultaneously and in parallel. Corresponding). At this time, the carrier tracking unit 34 is given an integrated value of the code Doppler obtained in the single code tracking loop by the code tracking unit 33. Then, the demodulator 13 performs code tracking and carrier frequency tracking using a concatenated code / carrier tracking loop. When the steady tracking is successful, the IF signal is despread by the obtained code and carrier frequency to perform navigation. Along with giving to the message acquisition unit 14, a pseudo distance or the like is calculated from the obtained code and carrier frequency information and given to the positioning unit 15.

  The navigation message acquisition unit 14 acquires a navigation message based on the despread signal on which the navigation message from the demodulation unit 13 is superimposed, and provides the navigation unit 15 with the navigation message.

  The positioning unit 15 performs a positioning calculation based on the navigation message from the navigation message acquisition unit 14, the pseudo distance from the demodulation unit 13, carrier frequency information, and the like, and calculates the position of the positioning device.

Next, the configuration of the demodulator 13 which is a characteristic part of the present invention will be specifically described with reference to FIGS.
FIG. 2 is a block diagram showing a main configuration of the demodulator 13 shown in FIG. 3A and 3B are diagrams for explaining the switching operation of the switching circuit 35 shown in FIG. 2, and FIG. 3C is a model showing the C / No characteristic of the transition time T. It is the graph showing.

  The demodulating unit 13 includes a correlator 31, an integrator 32, a code tracking unit 33, a carrier tracking unit 34, a switching circuit 35, a C / No measurement unit 36, a tracking processing control unit 37, and a pseudo distance calculation unit 38.

  The correlator 31 performs correlation processing on the IF signal as described above. The correlator 31 includes a carrier correlator, a code correlator, a replica carrier frequency signal generation unit, and a replica code signal generation unit.

  At the time of signal acquisition, the correlator 31 generates a replica carrier frequency signal and a replica code signal by a known search code carrier frequency generation method, performs correlation using the carrier correlator and the code correlator, and acquires the signal (search). I do. When the correlator 31 detects that a preset search C / No threshold has been exceeded, the correlator 31 switches to the correlation processing for tracking.

  The tracking correlation processing is different between the single code tracking loop processing and the concatenated code carrier tracking loop processing. In the case of single code tracking loop processing, the correlator 31 generates a replica code signal based on the code information output from the code tracking unit 33, and generates a replica carrier frequency signal based on the carrier frequency at the end of the search. . On the other hand, in the case of a concatenated code / carrier tracking loop, the correlator 31 generates a replica code signal based on the code information output from the code tracking unit 33 and based on the carrier frequency information output from the carrier tracking unit 34. To generate a replica carrier frequency signal.

  The carrier correlator of the correlator 31 performs correlation processing between the IF signal and the replica carrier frequency signal, and the code correlator performs correlation processing between the IF signal after carrier correlation and the replica code signal.

  The integrator 32 converts the IF signal after the correlation processing into a predetermined time length, for example, 1 [msec. ] To generate a despread signal. The despread signal is given to the navigation message acquisition unit 14 and is also given to the code tracking unit 33, the carrier tracking unit 34, and the C / No measurement unit 36.

  The C / No measurement unit 36 sequentially measures the C / No (carrier power to noise power density ratio) of the despread signal output from the accumulator 32 and provides it to the tracking processing control unit 37.

  The tracking process control unit 37 corresponding to the switching timing instruction means of the present invention determines a transition time T for setting a timing for supplying a switching control signal to the switching circuit 35 based on the acquired C / No. Here, as shown in FIG. 3C, the transition time T is set shorter as the C / No becomes higher, that is, the noise is smaller and the C / No becomes better, and the C / No becomes lower, that is, the noise. The longer the C / No is, the longer it is set. Furthermore, the transition time T is set so as to become a negative exponential function with respect to C / No. For example, the tracking process control unit 37 integrates the reciprocal (1 / T) of the transition time T determined in this way for each unit time composed of preset equal time intervals. Then, the tracking process control unit 37 determines the time point when the integration result reaches the predetermined threshold as the switching timing, and provides a switching control signal to the switching circuit 35. In this way, by determining the transition time T and calculating the switching timing, if the C / No is high, the code tracking unit 33 and the carrier tracking unit 34 are linked from the single code tracking loop by the code tracking unit 33. The switching timing to the connected code carrier tracking loop can be made earlier. On the other hand, if C / No is low, the switching timing from the single code tracking loop to the concatenated code carrier tracking loop can be delayed. Furthermore, if the speed at which the C / No increases from a low state is high, the switching timing from the single code tracking loop to the linked code / carrier tracking loop can be made earlier than when the speed at which the C / No increases is slow. it can. At this time, the lower the C / No, the longer the execution time length of the single code tracking loop. Therefore, if the C / No has a level exceeding the search threshold, the C / No is surely increased without being affected by the C / No. Accurate code tracking can be performed.

  Note that the tracking process control unit 37 may sequentially accumulate C / No given from the C / No measuring unit 36, and may determine the time when the accumulated value reaches a predetermined threshold as the switching timing.

  The code tracking unit 33 includes a code NCO 330, a code phase difference detection unit 331, a first unit conversion unit 332, a first amplifier 333, a second amplifier 334, an accumulator 335, an adder 336, and a second unit conversion unit 337.

  The code phase difference detection unit 331 detects the code phase difference included in the despread signal, that is, the code phase difference between the replica code signal generated based on the code information of the code NCO 330 and the IF signal, and the first unit This is given to the conversion unit 332. The first unit conversion unit 332 converts the code phase difference based on the code chip unit into a code phase difference in time units, and outputs the code phase difference to the first amplifier 333 and the second amplifier 334.

  The first amplifier 333 outputs a code phase baseband component, and the second amplifier 334 is set to gain so as to output a code Doppler component with respect to the code phase. At this time, the first amplifier 333 and the second amplifier 334 are set with a bandwidth corresponding to the C / No at each timing. The code phase difference obtained from the first amplifier 333 is input to the adder 336. On the other hand, the code phase difference obtained from the second amplifier 334 is input to the integrator 335.

  The accumulator 335 sequentially accumulates the code phase differences obtained from the second amplifier 334. Here, since the code phase difference accumulated in the accumulator 335 is a code Doppler component generated by the movement of the positioning satellite or the like, the code Doppler component is accumulated by accumulating these. As a result, processing corresponding to integrating carrier frequencies can be performed. The integrated value of the code phase difference is input to the switching circuit 35.

  The switching circuit 35 includes a switch 351 and a switch 352. The switch 351 can switch the opening and closing of the connection between the integrator 335 of the code tracking unit 33 and the carrier tracking unit 34. The switch 352 connects the adder 336 of the code tracking unit 33 to either the integrator 335 or the carrier tracking unit 34 of the code tracking unit 33. Switching control of the switches 351 and 352 of the switching circuit 35 is performed by a switching control signal from the tracking processing control unit 37 described above.

  At the end of the search, no switching control signal is given from the tracking processing control unit 37, and as shown in FIG. 3A, the switch 351 is open, and the switch 352 is an accumulator 335 and an adder 336. And connect. As a result, a secondary feedback loop for the single code tracking loop process by the code tracking unit 33, the correlator 31, and the accumulator 32 is formed.

  When the single code tracking loop processing is executed, the integrated value of the code phase difference input from the accumulator 335 to the switching circuit 35 is given to the adder 336, and the adder 336 receives the baseband component via the first amplifier 333. The code phase difference and the integrated value of the code phase difference of the code Doppler component via the second amplifier 334 and the integrator 335 are added and output to the second unit converter 337.

  The second unit conversion unit 337 converts the code phase difference in units of time into code phase differences in units of code chips and provides the code NCO 330 with the code phase difference. The code NCO 330 generates code information for generating a replica code signal at the next timing based on the given code phase difference, and outputs the code information to the correlator 31.

  On the other hand, when a switching control signal is input from the tracking processing control unit 37 and the switching control of each of the switches 351 and 352 is performed, the switch 351 is short-circuited as shown in FIG. The integrator 335 and the carrier tracking unit 34 are connected, and the switch 352 connects the carrier tracking unit 34 and the adder 336 of the code tracking unit 33.

  The carrier tracking unit 34 includes a carrier tracking execution unit 341, a third unit conversion unit 342, and a fourth unit conversion unit 343. The carrier tracking execution unit 341 has a known configuration such as a carrier NCO and a carrier difference detection unit, performs various processes related to carrier tracking, and outputs carrier frequency information to the correlator 31. The carrier tracking execution unit 341 does not operate while the single code tracking loop is executed, and starts the carrier tracking from the time when the switching control signal is performed and the code tracking unit 33 is connected. At the start of carrier tracking, the carrier tracking execution unit 341 converts the integrated value of the code phase difference input from the integrator 335 of the code tracking unit 33 from a time unit to a frequency unit by the fourth unit conversion unit 343. That is, the carrier frequency in the single code tracking loop processing period is received, an initial value is set, and carrier tracking is started. Thereby, a highly accurate carrier frequency initial value can be given to the carrier tracking loop, and reliable and highly accurate carrier tracking can be performed.

  Then, the carrier tracking execution unit 341 outputs the calculated carrier frequency information to the correlator 31, the third unit conversion unit 342, and the positioning unit 15.

  The third unit conversion unit 342 converts the carrier frequency information obtained by the carrier tracking execution unit 341 into a change rate of time, that is, a time unit, and supplies the converted information to the switching circuit 35. At this time, the third unit conversion unit 342 performs conversion at a conversion rate according to the code to be tracked. The carrier frequency information converted into the time unit is input to the adder 336 of the code tracking unit 33 via the switch 352. The adder 336 adds the above-described baseband component code phase difference obtained by the code tracking unit 33 and the carrier frequency information converted into time units, and outputs the result. With such a configuration, a concatenated code / carrier tracking loop including the code tracking unit 33, the carrier tracking unit 34, the correlator 31, and the accumulator 32 is configured, and the code and the carrier frequency are tracked in parallel. Can do.

  The pseudo distance calculation unit 38 calculates a pseudo distance based on the code phase difference from the code tracking unit 33, the carrier frequency information of the carrier tracking unit 34, and the like, and provides the pseudo distance to the positioning unit 15.

  Next, a simulation result when the configuration of the present embodiment is used will be described. FIG. 4 shows whether the carrier frequency error could be estimated within 100 [Hz] using the carrier signal type, the initial carrier frequency error at the end of the search, and the C / No when ideally tracked as parameters. .

  As shown in FIG. 4, by using the configuration of the present embodiment, when an L1 wave C / A code is used, even if the initial carrier frequency error is 550 [Hz], the C / No is 35 [dB- [Hz] or higher, the carrier frequency can be estimated within an error of 100 [Hz]. Further, when an L1 wave C / A code is used and the initial carrier frequency error is 300 [Hz], the carrier is within 100 [Hz] even if C / No is 30 [dB-Hz]. The frequency can be estimated. Furthermore, when the C / A code of the L1 wave is used, the frequency estimation time can be significantly shortened as the C / No is improved.

  Also, when the L5 wave I code is used, even if the initial carrier frequency error is 550 [Hz], if the C / No is 50 [dB-Hz] or more, the carrier frequency is within 100 [Hz]. Can be estimated. Further, when the L5 wave I code is used and the initial carrier frequency error is 300 [Hz], the carrier frequency is within 100 [Hz] even if C / No is 35 [dB-Hz]. Can be estimated.

  FIG. 5 shows simulation results when the configuration of the present embodiment is used under the same conditions as FIG. 6 showing the conventional case. FIGS. 5A and 5B are GPS L1 wave C / A codes. FIGS. 5C and 5D are diagrams showing simulation results of the carrier frequency transition state and C / No (carrier power to noise power density ratio) transition state for FIGS. It is a figure which shows a transition condition and a C / No transition condition.

  As described above, by using the configuration of the present embodiment, adverse effects on tracking due to C / No are suppressed, and code tracking and carrier frequency tracking can be performed reliably and with high accuracy even in a noise environment worse than the conventional one. It can be carried out. Further, even if the initial carrier frequency error is larger than that in the prior art, code tracking and carrier frequency tracking can be performed reliably and with high accuracy.

It is a block diagram which shows schematic structure of the positioning apparatus containing the demodulation part corresponded to the positioning signal demodulation apparatus which concerns on embodiment of this invention. It is a block diagram which shows the main structures of the demodulation part 13 shown in FIG. FIG. 3 is a diagram for explaining a switching operation of the switching circuit 37 shown in FIG. 2 and a graph showing one model showing a C / No characteristic of a transition time T. FIG. It is the table | surface which showed the simulation result of the tracking which used the kind of carrier wave signal, the initial carrier frequency error at the time of a search end, and C / No as a parameter. It is the figure which showed the simulation result of the tracking at the time of using the structure of this embodiment. It is the figure which showed the simulation result of the conventional tracking.

Explanation of symbols

11-positioning signal receiving antenna, 12-down converter, 13-demodulation unit, 14-navigation message acquisition unit, 15-positioning unit,
31-correlator, 32-accumulator, 33-code tracking unit, 34-carrier tracking unit, 35-switching circuit, 36-C / No measurement unit, 37-tracking processing control unit, 38-pseudo distance calculation unit,
330-code NCO, 331-code phase detector, 332-first unit converter, 333-first amplifier, 334-second amplifier, 335-accumulator, 336-adder, 337-second unit converter, 341-carrier tracking execution unit, 342-third unit conversion unit, 343-fourth unit conversion unit, 351, 352-switch

Claims (6)

A positioning signal tracking processing device comprising a carrier tracking unit that tracks a carrier frequency based on a positioning signal, and a code tracking unit that tracks a code based on the positioning signal,
C / No estimation means for estimating C / No of the positioning signal subjected to predetermined correlation processing;
Carrier frequency estimation means provided in the code tracking unit, for estimating a carrier frequency over a predetermined time based on a code Doppler component detected by the code tracking unit;
An estimated time determining means for determining a predetermined time for estimating the carrier frequency based on the C / No,
The positioning signal tracking processing device, wherein the carrier tracking unit performs tracking of the carrier frequency using the carrier frequency estimated by the carrier frequency estimating means as an initial value.   The positioning signal processing tracking device according to claim 1, wherein the estimation time determination unit shortens the predetermined time for estimating the carrier frequency as the C / No is improved.   The estimated time determining means sets a transition time that becomes shorter as the C / No becomes better, integrates the reciprocal of the transition time at each preset timing, and takes a time until the integrated value reaches a predetermined value. The positioning signal tracking processing apparatus according to claim 1 or 2, wherein a predetermined time for estimating the carrier frequency is used.   The estimated time determining means integrates the C / No at each preset timing, and sets a time until the integrated value reaches a predetermined value as a predetermined time for estimating the carrier frequency. Or the positioning signal tracking processing apparatus of Claim 2. The code tracking unit includes a code phase difference detection unit that detects a code phase difference between a code superimposed on the positioning signal and a replica code generated by a code NCO, and on the output side of the code phase difference detection unit, The first system and the second system having amplifiers having different gains are provided, and the second system is inserted with the accumulator for integrating the code Doppler component of the code phase over the predetermined time. And
The carrier frequency estimation means includes the code phase difference detection unit, the second system amplifier, and the second system integrator,
The positioning signal tracking processing device according to any one of claims 1 to 4, wherein the carrier tracking unit performs tracking of the carrier frequency using a carrier frequency based on a value output from the accumulator as the initial value. . A demodulation unit that has the positioning signal tracking processing device according to any one of claims 1 to 5 and calculates a pseudorange based on a code phase difference and a carrier frequency of a tracked code;
A navigation message acquisition unit for acquiring a navigation message from the positioning signal demodulated by the demodulation unit;
A positioning device comprising: a positioning unit that performs a positioning calculation using the pseudo distance and the navigation message.

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