CN114236578B - Satellite navigation signal tracking method under non-omnidirectional single-antenna rotation condition - Google Patents
Satellite navigation signal tracking method under non-omnidirectional single-antenna rotation condition Download PDFInfo
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Abstract
A satellite navigation signal tracking method under a non-omnidirectional single antenna rotation condition utilizes the characteristic that a signal of a non-omnidirectional single antenna satellite navigation receiver is periodically interrupted or weakened under the rotation condition, calculates a total integral result by using only a subsection integral result with an energy value larger than or equal to a threshold in an integral remover of a satellite signal tracking loop, and performs normalization processing, so that the pollution of the total integral result by the subsection integral result with a low energy value can be avoided, noise and interference in the total integral result are reduced, the proportion of useful information in the total integral result is improved, and the tracking capacity and the positioning capacity of the receiver under the non-omnidirectional single antenna rotation condition are improved.
Description
Technical Field
The invention relates to a satellite navigation receiver technology under a non-omnidirectional single antenna rotation condition, in particular to a satellite navigation signal tracking method under the non-omnidirectional single antenna rotation condition, which utilizes the characteristic that a signal of a satellite navigation receiver with the non-omnidirectional single antenna is periodically interrupted or weakened under the rotation condition, calculates a total integral result by using only a subsection integral result with an energy value larger than or equal to a threshold in an integral remover of a satellite signal tracking loop, and performs normalization processing, thereby avoiding pollution of the total integral result by the subsection integral result with a low energy value, reducing noise and interference in the total integral result, and improving the specific gravity of useful information in the total integral result, thereby improving the tracking capacity and positioning capacity of the receiver under the non-omnidirectional single antenna rotation condition.
Background
The global satellite navigation system (GNSS, global Navigation SATELLITE SYSTEM) is a system with positioning, navigation and time service functions, which consists of three parts of a space part, a ground monitoring part and a user receiver, and is applied to civil fields, industry fields and military fields such as navigation, aviation, survey and mapping, precise positioning and the like. Currently, the global satellite navigation system mainly includes the GPS in the united states, GLONASS in russia, BDS in china, GALILEO system in europe, and so on. The satellite navigation user receiver comprises three modules, namely radio frequency front end processing, baseband signal processing and navigation positioning resolving. Baseband signal processing includes acquisition, tracking, bit synchronization, frame synchronization, and the like.
Because of the relative motion between the satellite and the receiver, and the frequency drift of the satellite clock and the receiver crystal oscillator, the carrier frequency and code phase of the satellite signal received by the receiver will change over time, so the satellite signal tracking method generally needs to operate continuously and periodically in the form of closed loop feedback to achieve continuous locking of the satellite signal, so the satellite signal tracking method is also called tracking loop. The signal tracking loop is actually composed of a carrier tracking loop and a code tracking loop, which are respectively used for tracking the carrier and the pseudo code in the received signal.
Fig. 1 is a schematic diagram of the tracking loop structure of a conventional satellite navigation receiver, which belongs to a common receiver tracking loop implementation. Firstly, an input intermediate frequency signal is multiplied by a carrier wave which is locally copied in a mixing way by adopting an I/Q demodulation way, namely an in-phase branch I is multiplied by a sine carrier wave, and a quadrature branch Q is multiplied by a cosine carrier wave; and the signals obtained by mixing are respectively subjected to related operation with the forward E branch, the instant P branch and the backward L branch spread spectrum pseudo codes copied by the code generator. And then, the correlation result is subjected to an integral cleaner to obtain corresponding coherent integral values, the coherent integral values of the instant P branch circuits are sent to a carrier ring discriminator, and the coherent integral values of the branch circuits are sent to a code ring discriminator. The carrier wave ring and the code ring respectively filter the output value of the discriminator and control the carrier wave numerical control oscillator and the pseudo code numerical control oscillator as feedback quantity.
In the instant P branch, the integrating scavenger removes high frequency signal components and noise in the signals i P (n) and q P (n) by integrating the low pass filter to improve the carrier to noise ratio. After the integrator integrates the input signals I P (n) and Q P (n) for a certain time, I P and Q P are output respectively, then the remover clears each register unit in the integrator, and then the integration of the next period is carried out, so that the process is repeated. The leading E branch and the lagging L branch are similar. The integration operation is performed by separating the I-path and the Q-path, which is called coherent integration, and the corresponding integration time is called coherent integration time. Since the tracking loop performs the discrimination processing using the integration results of the I-way and Q-way, the integration results described below are also coherent integration results.
The carrier rolling gesture detection can be performed by utilizing the periodical amplitude modulation information of the non-omni-directional antenna receiving signal under the rotation condition, so that the functions of positioning and rolling gesture measurement can be simultaneously realized by adopting a single satellite navigation receiver measurement module, and the method is an easy-to-implement carrier position detection and rolling gesture detection solution with high efficiency and cost ratio. However, on one hand, the energy of the received satellite signal is uneven and discontinuous in the rotation process of the antenna, so that the amplitude of the received signal periodically fluctuates, and half of the time of the antenna is blocked by the carrier to cause interruption of the received signal; on the other hand, the received signal also contains modulation interference of the carrier doppler frequency and phase due to rotation. When the rotation speed is low, the signal interruption interval is long, and the receiver is very easy to frequently exit the tracking loop; when the rotation speed is higher, although the signal interruption interval is shortened, the carrier Doppler frequency change range caused by rotation is greatly increased, and even the carrier Doppler frequency change range exceeds the frequency range which can be tracked by the tracking loop, so that the situation that the receiver frequently exits the tracking loop also occurs, the tracking loop of the conventional receiver is unlocked, and the positioning of the receiver is difficult.
Disclosure of Invention
Aiming at the defects or shortcomings in the prior art, the invention provides a satellite navigation signal tracking method under the rotation condition of a non-omni-directional single antenna, which utilizes the characteristic that a satellite navigation receiver with the non-omni-directional single antenna periodically interrupts or weakens signals under the rotation condition, calculates the total integral result by using only the sub-segment integral result with the energy value larger than or equal to a threshold in an integral remover of a satellite signal tracking loop, and performs normalization processing, thereby avoiding pollution of the total integral result by the sub-segment integral result with low energy value, reducing noise and interference in the total integral result, improving the specific gravity of useful information in the total integral result, and further improving the tracking capacity and positioning capacity of the receiver under the rotation condition of the non-omni-directional single antenna.
The technical scheme of the invention is as follows:
A satellite navigation signal tracking method under a non-omnidirectional single antenna rotation condition is characterized by comprising the steps of utilizing the characteristic that a signal of a non-omnidirectional single antenna satellite navigation receiver is periodically interrupted or weakened under the rotation condition, carrying out equivalent energy value conversion on a sub-section integral result in a total integral time period, comparing the equivalent energy value of the sub-section integral result with a preset energy threshold value, calculating the total integral result by using only the sub-section integral result with the energy value larger than or equal to a threshold in an integral remover of a satellite signal tracking loop, avoiding pollution of the total integral result by the sub-section integral result with the low energy value, improving the specific gravity of useful information in the total integral result in normalization processing, reducing noise and interference in the total integral result, and further improving the tracking capacity and positioning capacity of the receiver under the non-omnidirectional single antenna rotation condition.
The total integration time period comprises N subsections, N is a positive integer, the number of subsections with equivalent energy value POWseg being larger than or equal to energy threshold POWth is Ns, ns is a positive integer, N is larger than or equal to Ns, and the total integration result=the summation result of the subsection integration results (N/Ns).
The total integration result includes a total integration result of the in-phase signal I whose sub-segment integration result is I seg and a total integration result of the quadrature signal Q whose sub-segment integration result is the positive square root of Q seg,POWseg＝{[iseg]2+[qseg]2, or POWseg = [ I seg]2+[qseg]2, or POWseg =max (|i seg|,|qseg |), or POWseg =max ([ I seg]2,[qseg]2).
The total integration result of the in-phase signal I includes a total integration result I P of the immediate P branch, a total integration result I E of the advanced E branch, and a total integration result I L of the retarded L branch, and the total integration result of the quadrature signal Q includes a total integration result Q P of the immediate P branch, a total integration result Q E of the advanced E branch, and a total integration result Q L of the retarded L branch.
And the sub-segment integration result is output from an FPGA or ASIC hardware circuit correlator, and the summation result of the sub-segment integration result is realized through a hardware accumulation circuit or through a software summation program.
One total integration period corresponds to one data code length, one sub-period corresponds to one ranging pseudocode, and the signal ranging pseudocode is periodic.
The software flow for calculating the total integral result of N subsections comprises the following steps:
Step 1, counting values k and Ns clear 0, total integration results Ip and Qp clear 0, wherein k is a positive integer, ns is a positive integer, N is greater than or equal to Ns, I is an in-phase branch, Q is a quadrature branch, Q and I have a phase difference of 90 degrees, ip is an instant P branch in-phase signal output total integration result, qp is an instant P branch quadrature-phase signal output total integration result, and an instant P branch belongs to a satellite signal tracking channel;
step 2, reading sub-segment coherent integration results i seg,p(k) and q seg,p(k), wherein i seg,p(k) and q seg,p(k) are an in-phase signal integration result and a quadrature signal integration result of a kth sub-segment of the instant P branch respectively;
step 3, calculating an equivalent energy value POW seg,p(k) of the sub-segment integral result;
Step 4, judging whether POW seg,p(k) is more than or equal to POWth, if yes, entering step 5, and if no, entering step 6, wherein POWth is an energy threshold value;
Step 5, summation: ip=ip+i seg,P(k),Qp＝Qp+Qseg,P(k), count: ns=ns+1;
step 6, counting: k=k+1;
step 7, judging whether k is equal to N, if so, entering step 8, and if not, returning to step 2, wherein N is a positive integer, and N is more than or equal to Ns;
Step 8, judging whether Ns is more than 0, if so, entering step 9, and if not, entering step 10;
step 9, normalizing the total integral result: ip=ip×n/Ns, qp=qp×n/Ns;
Step 10, returning to step1 after outputting the total integration results Ip and Qp.
The invention has the following technical effects: the invention discloses a satellite navigation signal tracking method under a non-omnidirectional single antenna rotation condition, which is applied to a satellite navigation receiver adopting a non-omnidirectional single antenna, wherein the receiver is loaded on a rotating carrier.
The invention improves the integral cleaner in the conventional satellite navigation signal tracking loop, reduces noise and interference in an integral result, and improves the proportion of useful information in the integral result, thereby improving the tracking capability of satellite signals under the condition of non-omnidirectional single antenna rotation. The invention modifies the calculation of the total integral result as follows: screening the integral results of each sub-segment, wherein the integral results with the energy value larger than or equal to a threshold are used for calculating the total integral result, and the integral results with the energy value smaller than the threshold are not used for calculating the total integral result; and normalizing the integral summation result of each subsection to obtain a total integral result. The invention uses the characteristic that the signal of the non-omnidirectional single-antenna satellite navigation receiver is periodically interrupted or weakened under the rotation condition, and in the integral remover of the satellite signal tracking loop, the total integral result is calculated by using only the sub-segment integral result with the energy value more than or equal to the threshold, and the normalization processing is carried out. The improvement can avoid pollution of the total integral result by the sub-segment integral result with low energy value, reduce noise and interference in the integral result, and improve the proportion of useful information in the integral result, thereby improving the tracking capability and positioning capability of the receiver under the non-omnidirectional single antenna rotation condition.
Drawings
Fig. 1 is a schematic diagram of the tracking loop structure of a conventional satellite navigation receiver. In fig. 1, the in-phase signal I (n) of the in-phase branch I, the quadrature signal Q (n) of the quadrature branch Q, the lead E branch (I E(n),qE(n), the coherent integration value I E,QE), the immediate P branch (I P(n),qP(n), the coherent integration value I P,QP), the lag L branch (I L(n),qL(n), the coherent integration value I L,QL), the sine table, the cosine table, the mixer, the code generator, the correlator, the integral remover, the code loop discriminator, the carrier loop discriminator, the code loop filter, the carrier loop filter, the code NCO offset, the carrier NCO, the carrier integrator.
Fig. 2 is a schematic software flow chart of calculating total integration results of N sub-segments of a satellite navigation signal tracking method under a non-omni-directional single antenna rotation condition. In fig. 2, step 1 is included, count values k and Ns clear 0, total integration result (Ip and Qp) clear 0, where k is a positive integer, ns is a positive integer, I is an In-phase branch, Q is a Quadrature branch, i=in-phase is In-phase, q=quadrature is Quadrature, Q is 90 degrees out of phase with I, ip is an instantaneous P-branch In-phase signal output total integration result, qp is an instantaneous P-branch Quadrature-phase signal output total integration result, and instantaneous P-branch belongs to a satellite signal tracking channel; step 2, reading sub-segment coherent integration results i seg,p(k) and q seg,p(k), wherein i seg,p(k) and q seg,p(k) are an in-phase signal integration result and a quadrature signal integration result of a kth sub-segment of the instant P branch respectively; step 3, calculating an equivalent energy value POW seg,p(k) of the sub-segment integral result; step 4, judging whether POW seg,p(k) is more than or equal to POWth, if yes, entering step 5, and if no, entering step 6, wherein POWth is an energy threshold value; step 5, summation: ip=ip+i seg,P(k),Qp＝Qp+Qseg,P(k), count: ns=ns+1; step 6, counting: k=k+1; step 7, judging whether k is equal to N, if so, entering step 8, and if not, returning to step 2, wherein N is a positive integer, and N is more than or equal to Ns; step 8, judging whether Ns is more than 0, if so, entering step 9, and if not, entering step 10; step 9, normalizing the total integral result: ip=ip×n/Ns, qp=qp×n/Ns; step 10, returning to step 1 after outputting the total integration results Ip and Qp.
Detailed Description
The invention is described below with reference to the figures (fig. 1-2) and examples.
Fig. 1 is a schematic diagram of the tracking loop structure of a conventional satellite navigation receiver. Fig. 2 is a schematic software flow chart of calculating total integration results of N sub-segments of a satellite navigation signal tracking method under a non-omni-directional single antenna rotation condition. Referring to fig. 1 to 2, a satellite navigation signal tracking method under a non-omni-directional single antenna rotation condition includes performing equivalent energy value conversion on sub-segment integration results in a total integration time period by using a characteristic that a signal of a non-omni-directional single antenna satellite navigation receiver is periodically interrupted or weakened under the rotation condition, comparing the equivalent energy value of the sub-segment integration results with a preset energy threshold value, calculating the total integration result by using only the sub-segment integration results with the energy value greater than or equal to a threshold in an integration remover of a satellite signal tracking loop, so as to prevent the sub-segment integration results with low energy value from polluting the total integration result, improving specific gravity of useful information in the total integration result in normalization processing, reducing noise and interference in the total integration result, and improving tracking capability and positioning capability of the receiver under the non-omni-directional single antenna rotation condition.
The total integration time period comprises N subsections, N is a positive integer, the number of subsections with equivalent energy value POWseg being larger than or equal to energy threshold POWth is Ns, ns is a positive integer, N is larger than or equal to Ns, and the total integration result=the summation result of the subsection integration results (N/Ns). The total integration result includes a total integration result of the in-phase signal I whose sub-segment integration result is I seg and a total integration result of the quadrature signal Q whose sub-segment integration result is the positive square root of Q seg,POWseg＝{[iseg]2+[qseg]2, or POWseg = [ I seg]2+[qseg]2, or POWseg =max (|i seg|,|qseg |), or POWseg =max ([ I seg]2,[qseg]2). The total integration result of the in-phase signal I includes a total integration result I P of the immediate P branch, a total integration result I E of the advanced E branch, and a total integration result I L of the retarded L branch, and the total integration result of the quadrature signal Q includes a total integration result Q P of the immediate P branch, a total integration result Q E of the advanced E branch, and a total integration result Q L of the retarded L branch. And the sub-segment integration result is output from an FPGA or ASIC hardware circuit correlator, and the summation result of the sub-segment integration result is realized through a hardware accumulation circuit or through a software summation program. One total integration period corresponds to one data code length, one sub-period corresponds to one ranging pseudocode, and the signal ranging pseudocode is periodic.
The software flow for calculating the total integral result of N subsections comprises the following steps: step 1, counting values k and Ns clear 0, total integration results Ip and Qp clear 0, wherein k is a positive integer, ns is a positive integer, N is greater than or equal to Ns, I is an in-phase branch, Q is a quadrature branch, Q and I have a phase difference of 90 degrees, ip is an instant P branch in-phase signal output total integration result, qp is an instant P branch quadrature-phase signal output total integration result, and an instant P branch belongs to a satellite signal tracking channel; step 2, reading sub-segment coherent integration results i seg,p(k) and q seg,p(k), wherein i seg,p(k) and q seg,p(k) are an in-phase signal integration result and a quadrature signal integration result of a kth sub-segment of the instant P branch respectively; step 3, calculating an equivalent energy value POW seg,p(k) of the sub-segment integral result; step 4, judging whether POW seg,p(k) is more than or equal to POWth, if yes, entering step 5, and if no, entering step 6, wherein POWth is an energy threshold value; step 5, summation: ip=ip+i seg,P(k),Qp＝Qp+Qseg,P(k), count: ns=ns+1; step 6, counting: k=k+1; step 7, judging whether k is equal to N, if so, entering step 8, and if not, returning to step 2, wherein N is a positive integer, and N is more than or equal to Ns; step 8, judging whether Ns is more than 0, if so, entering step 9, and if not, entering step 10; step 9, normalizing the total integral result: ip=ip×n/Ns, qp=qp×n/Ns; step 10, returning to step 1 after outputting the total integration results Ip and Qp.
A satellite navigation signal tracking method under the condition of non-omni-directional single antenna rotation is applied to a satellite navigation receiver adopting the non-omni-directional single antenna, and the receiver is loaded on a rotating carrier. The invention provides an improved satellite navigation signal tracking method in a baseband signal processing module aiming at the condition, and aims to solve the defects of the conventional satellite navigation signal tracking method under the condition, and provides a novel satellite signal tracking method which can improve the tracking capacity of signals, so that an antenna can track satellite signals better when the rotation speed is low or high, and the positioning capacity of a receiver under the application condition is improved. The invention improves the integral cleaner in the conventional satellite navigation signal tracking loop, reduces noise and interference in an integral result, and improves the proportion of useful information in the integral result, thereby improving the tracking capability of satellite signals under the condition of non-omnidirectional single antenna rotation.
In a conventional satellite navigation signal tracking loop, the total coherent integration time T total＝N*Tsegment (N is a positive integer) of the integral remover is taken as an example of an instant P branch of a satellite signal tracking channel, and the integration result of each sub-segment of the integration time T segment is recorded as i seg,P (k) and q seg,P (k), k=1, …, N, and other branches are similar. The total integral result is
The invention modifies the calculation of the total integral result as follows: screening the integral results of each sub-segment, wherein the integral results with the energy value larger than or equal to a threshold are used for calculating the total integral result, and the integral results with the energy value smaller than the threshold are not used for calculating the total integral result; and normalizing the integral summation result of each subsection to obtain a total integral result. The specific calculation steps are as follows (taking a satellite signal tracking channel instant P branch as an example, other branches and other channels are similar to the above):
(1) Screening the integral result of each subsection
And N s(0≤Ns is less than or equal to N) is the number of the energy values POW seg,P(k)≥POWth in each T total time period.
Wherein, POW seg,P (k) is the equivalent energy value of the integral result of each sub-segment, and the calculation can be selected from the following methods.
Method 1:
method 2: POW (Power over fiber) seg,P(k)＝[iseg,P(k)]2+[qseg,P(k)]2
Method 3: POW seg,P(k)＝max(|iseg,P(k)|,|qseg,P (k)
Method 4: POW seg,P(k)＝max([iseg,P(k)]2,[qseg,P(k)]2
The POW th can be obtained by experimental tests or data simulation aiming at different scenes; POW th can also be obtained by obtaining and processing the noise energy value by the same calculation method as POW seg,P (k) for the I-and Q-way data (I seg,P (k) and Q seg,P (k) values) of the noise channel.
(2) Normalization of the summation result to obtain a total integration result
It should be noted that, the noise channel is a special tracking channel in the tracking loop, and the pseudo code generated by the code generator of the tracking channel is different from the pseudo code of the satellite signal in the visible sky at the current position at any current moment. The i seg,P (k) and q seg,P (k) values of the noise channel are therefore available for noise estimation.
According to the calculation steps, the influence of an integral result of a signal interruption period is removed by utilizing the characteristic of periodic interruption of satellite signals under the non-omni-directional single antenna rotation condition, so that the tracking capacity of a loop is improved. In addition, it is noted that when the antenna is in a more serious shielding period, the received satellite signal will be in a weak signal period, which can lead to low energy value of the integration result of the corresponding sub-segment; when the antenna is at high rotational speeds, in certain sub-segments of the same total integration period, the true carrier doppler frequency is outside the tracking loop frequency range relative to the carrier doppler frequency recovered locally for that total integration period, resulting in low energy values of the integration results for these sub-segments, and the sub-segment integration results for these low energy values contain very low correct information and, if used to calculate the total integration result, can also contaminate the total integration result. Therefore, properly increasing the POW th threshold value can also remove the integral result of the weak signal sub-segment and the sub-segment of which the carrier doppler frequency exceeds the range of the tracking loop at high rotating speed, and improve the tracking capability of the tracking loop.
In a conventional satellite navigation receiver, the integral result of each sub-segment is usually output from an FPGA or ASIC hardware circuit correlator, while the total integral result of N sub-segments has different schemes, some manufacturers are realized by a hardware accumulation circuit, and some manufacturers are realized by a software summation program. The strategy of the invention is to modify the calculation of the total integral result of N subsections, and the calculation can also be realized by hardware or software. Taking a software implementation as an example, the flowchart is shown in fig. 2 (taking the instant P branch as an example, other branches are similar). The flow chart is a program implementation flow of the foregoing calculation step, wherein the bolded content in the flow chart is the added content of the present invention relative to the conventional receiver, and the rest is the implementation flow of the conventional receiver for calculating the total integration result of N sub-segments.
Taking an example of L1C/a signal reception in a GPS system in a receiver, the signal ranging pseudo code is periodic, the pseudo code rate is 1.023Mbps, the number of chips in each period is 1023 (i.e. the time period is 1 ms), and 20 ranging pseudo code periods (i.e. 20 ms) are contained in one data code width. The integral remover in the tracking loop usually takes one ranging pseudocode as a subsection, i.e. the integral time of each subsection is 1ms; the total integration time of coherent integration is typically one data code length. Thus, T total＝20ms,Tsegment = 1ms, n = 20. The instant P branch is taken as an example for description, and other branches are similar. Let i seg,P (k) and q seg,P (k) be the 1ms coherent integration result of the instant P branch of a certain satellite signal tracking channel, calculated by the correlator in the baseband chip, and periodically (with a reading interval less than 1 ms) read out from the baseband chip by the processor. The total integration result of the 20 subsections is realized in the flow of fig. 2 by software. In order to reduce the calculation amount, in the exemplary receiver, an equivalent energy value POW seg,P (k) of the 1ms sub-segment integration result is calculated by adopting the method 3; the POW th is obtained in real time by the following method: the value of 2000 max (i seg,P(k)|,|qseg,P (k) i) of the noise channel every 2 seconds is calculated (method 3 above), and twice the average value is taken as the POW th threshold value of the next 2 second period.
What is not described in detail in the specification belongs to the prior art known to those skilled in the art. It is noted that the above description is helpful for a person skilled in the art to understand the present invention, but does not limit the scope of the present invention. Any and all such equivalent substitutions, modifications and/or deletions as may be made without departing from the spirit and scope of the invention.
Claims (7)
1. A satellite navigation signal tracking method under a non-omnidirectional single antenna rotation condition is characterized by comprising the steps of utilizing the characteristic that a signal of a non-omnidirectional single antenna satellite navigation receiver is periodically interrupted or weakened under the rotation condition, carrying out equivalent energy value conversion on a sub-section integral result in a total integral time period, comparing the equivalent energy value of the sub-section integral result with a preset energy threshold value, calculating the total integral result by using only the sub-section integral result with the energy value larger than or equal to a threshold in an integral remover of a satellite signal tracking loop, avoiding pollution of the total integral result by the sub-section integral result with the low energy value, improving the specific gravity of useful information in the total integral result in normalization processing, reducing noise and interference in the total integral result, and further improving the tracking capacity and positioning capacity of the receiver under the non-omnidirectional single antenna rotation condition.
2. The method for tracking satellite navigation signals under the condition of non-omni-directional single antenna rotation according to claim 1, wherein the total integration time period includes N subsections, N is a positive integer, the number of subsections with an equivalent energy value POWseg being greater than or equal to an energy threshold POWth is Ns, ns is a positive integer, N is greater than or equal to Ns, and the total integration result = the summation result of the subsections is x (N/Ns).
3. The method of claim 1, wherein the total integration result includes a total integration result of an in-phase signal I and a total integration result of a quadrature signal Q, wherein the sub-segment integration result of the in-phase signal I is iseg, and wherein the sub-segment integration result of the quadrature signal Q is qseg, POWseg = { [ iseg ] 2+[qseg]2 } or POWseg = [ iseg ] 2+[qseg]2, or POWseg =max (| iseg |, | qseg |), or POWseg =max ([ iseg ] 2,[qseg]2).
4. A method of tracking satellite navigation signals under non-omni-directional single antenna rotation according to claim 3, wherein the total integration result of the in-phase signal I comprises the total integration result IP of the immediate P branch, the total integration result IE of the advanced E branch, and the total integration result IL of the retarded L branch, and the total integration result of the quadrature signal Q comprises the total integration result QP of the immediate P branch, the total integration result QE of the advanced E branch, and the total integration result QL of the retarded L branch.
5. The method for tracking satellite navigation signals under the condition of non-omni-directional single antenna rotation according to claim 1, wherein the sub-segment integration result is output from an FPGA or ASIC hardware circuit correlator, and the summation result of the sub-segment integration result is implemented by a hardware summation circuit or by a software summation program.
6. The method of claim 1, wherein a total integration period corresponds to a data code length, a sub-period corresponds to a ranging pseudocode, and the signal ranging pseudocode is periodic.
7. The method for tracking satellite navigation signals under non-omni-directional single antenna rotation according to claim 1, wherein the software process for calculating the total integration result of N sub-segments comprises the steps of:
Step 1, counting values k and Ns clear 0, total integration results Ip and Qp clear 0, wherein k is a positive integer, ns is a positive integer, N is greater than or equal to Ns, I is an in-phase branch, Q is a quadrature branch, Q and I have a phase difference of 90 degrees, ip is an instant P branch in-phase signal output total integration result, qp is an instant P branch quadrature-phase signal output total integration result, and an instant P branch belongs to a satellite signal tracking channel;
step 2, reading the sub-segment coherent integration results iseg, P (k) and qseg, P (k), wherein iseg, P (k) and qseg, P (k) are the instant P branch k sub-segment in-phase signal integration result and quadrature signal integration result respectively;
Step 3, calculating an equivalent energy value POWseg, p (k) of the integral result of the sub-segment;
Step 4, judging whether POWseg and p (k) are larger than or equal to POWth, if yes, entering step 5, and if no, entering step 6, wherein POWth is an energy threshold value;
step 5, summation: ip=ip+ iseg, P (k), qp=qp+qseg, P (k), count: ns=ns+1;
step 6, counting: k=k+1;
step 7, judging whether k is equal to N, if so, entering step 8, and if not, returning to step 2, wherein N is a positive integer, and N is more than or equal to Ns;
Step 8, judging whether Ns is more than 0, if so, entering step 9, and if not, entering step 10;
step 9, normalizing the total integral result: ip=ip×n/Ns, qp=qp×n/Ns;
Step 10, returning to step1 after outputting the total integration results Ip and Qp.
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