阅读说明：本技术 应用于卫星信号捕获的检测方法及装置 (Detection method and device applied to satellite signal acquisition ) 是由 宋挥师 刘晓燕 徐雄伟 赵海龙 于 2020-12-22 设计创作，主要内容包括：本文公开了一种应用于卫星信号捕获的检测方法及装置,包括：根据预先设定的门限值、以及当前搜索单元在此轮搜索的检测值进行检测判决；判定此轮搜索在当前搜索单元捕获成功时,第一计数器进行累加计数,在所述第一计数器的值达到预设的第一最大值时,停止计数,并指示在当前搜索单元成功捕获到当前卫星信号；判定此轮搜索在当前搜索单元捕获失败时,第二计数器进行累加计数,在所述第二计数器的值达到预设的第二最大值时,停止计数,并指示在当前搜索单元捕获当前卫星信号失败。本申请能够避免计数振荡,缩短捕获时长,减少检测次数,进而提高检测性能。(The utility model discloses a detection method and a device applied to satellite signal acquisition, comprising: carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit; when the acquisition success of the current search unit in the round of search is judged, a first counter carries out accumulated counting, and when the value of the first counter reaches a preset first maximum value, the counting is stopped, and the successful acquisition of the current satellite signal in the current search unit is indicated; and when the acquisition failure of the current search unit in the round of search is judged, the second counter carries out accumulated counting, and when the value of the second counter reaches a preset second maximum value, the counting is stopped, and the failure of the current search unit in acquiring the current satellite signal is indicated. The method and the device can avoid counting oscillation, shorten capture time, reduce detection times and further improve detection performance.)

1. A detection method applied to satellite signal acquisition, comprising:

carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

when the acquisition success of the current search unit in the round of search is judged, a first counter carries out accumulated counting, and when the value of the first counter reaches a preset first maximum value, the counting is stopped, and the successful acquisition of the current satellite signal in the current search unit is indicated;

and when the acquisition failure of the current search unit in the round of search is judged, the second counter carries out accumulated counting, and when the value of the second counter reaches a preset second maximum value, the counting is stopped, and the failure of the current search unit in acquiring the current satellite signal is indicated.

2. The detection method according to claim 1, further comprising:

and when the current search unit fails to capture, detecting the signal quality change condition of the current search unit according to the detection value obtained by the current search unit in the current search, the detection value obtained by the current search unit in the previous search and the threshold value, and adjusting the first maximum value or the second maximum value according to the signal quality change condition of the current search unit.

3. The method according to claim 2, wherein the detecting the signal quality variation of the current searching unit and adjusting the first maximum value and/or the second maximum value according to the signal quality variation of the current searching unit comprises:

verifying whether one of the following relationships is satisfied:

V_n>V_n-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value;

if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value;

wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating the detected value, V, obtained by the current search unit in the previous search_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1A preset initial value is taken, and Q is a preset fixed value.

4. The detection method according to claim 1, further comprising:

after the accumulated counting, when the value of the first counter does not reach a preset first maximum value, the first counter keeps a current counting value and indicates that additional searching needs to be continued in a current searching unit; and/or the presence of a gas in the gas,

and after the accumulated count, when the value of the second counter does not reach a preset second maximum value, the second counter keeps the current count value and indicates that additional search needs to be continued in the current search unit.

5. The detection method according to claim 1, further comprising:

and when the current search unit fails to acquire the current satellite signal, resetting the values of the first counter and the second counter to initial values and indicating to enter the search of the next search unit.

6. A detection apparatus for use in satellite signal acquisition, comprising:

the comparator is used for carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

the first counter is used for performing accumulated counting when the comparator judges that the current search unit is successfully acquired, stopping counting when the value after accumulated counting reaches a preset first maximum value, and indicating that the current satellite signal is successfully acquired by the current search unit;

and the second counter is used for performing accumulated counting when the comparator judges that the current search unit fails to acquire the current satellite signal, stopping counting when the value after the accumulated counting reaches a preset second maximum value, and indicating that the current search unit fails to acquire the current satellite signal.

7. The detection device of claim 6, further comprising:

the self-adaptive discriminator is used for detecting the signal quality change condition of the current searching unit according to the detection value obtained by the current searching unit in the round of searching, the detection value obtained by the current searching unit in the previous round of searching and the threshold value when the comparator judges that the round of searching fails to be captured in the current searching unit;

a first adjuster for adjusting the first maximum value according to a detection result of the adaptive discriminator; and/or a second adjuster for adjusting the second maximum value according to the detection result of the adaptive discriminator.

8. The detection apparatus according to claim 7,

the adaptive discriminator is specifically configured to:

verifying whether one of the following relationships is satisfied:

V_n>V_n-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value; if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value; wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating that the current search unit was obtained in the previous search roundDetected value of (2), V_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1Taking a preset initial value, wherein Q is a preset fixed value;

the first adjustor is specifically configured to increase the first maximum value when the adaptive discriminator determines that the signal quality of the current search unit is becoming better; and/or the second adjustor is specifically configured to decrease the second maximum value when the adaptive discriminator determines that the signal quality of the current search unit is deteriorating.

9. The detection apparatus according to claim 6,

the first counter is further used for keeping the current count value and indicating that additional search needs to be continued in the current search unit when the value after the accumulated count does not reach the preset first maximum value; and/or the presence of a gas in the gas,

and the second counter is further used for keeping the current count value and indicating that additional search needs to be continued in the current search unit when the value after the accumulated count does not reach a preset second maximum value.

10. A navigation receiver, characterized in that it comprises detection means for satellite signal acquisition as claimed in any one of claims 6 to 9.

Technical Field

The present invention relates to the field of navigation technologies, and in particular, to a detection method and apparatus applied to satellite signal acquisition.

Background

Navigation technology plays an important role in the development process of human history, and along with the continuous progress of society, the technology, particularly satellite navigation positioning technology, is more and more closely related to the life of people. Currently, the main Satellite NAvigation systems in the world include a Global Positioning System (GPS), a BD2 (the second beidou), a Global NAvigation Satellite System (GLONASS), and a Galileo (Galileo) Satellite NAvigation System. Both GPS and BD2 use CDMA (Code Division Multiple Access) technology, and the physical layer frame structures thereof are much similar, so that the receiver design is similar, including rf front end processing, baseband digital signal processing, and positioning navigation operations. The baseband digital signal processing process generally includes acquisition, tracking, bit synchronization, frame synchronization, and the like.

The acquisition process of the satellite navigation receiver to the satellite signal includes frequency mixing, correlation operation, coherent integration/non-coherent integration and decision, and the principle of navigation signal acquisition is shown in fig. 1. The decision device compares the detected quantity obtained by the previous operation with the decision threshold, thereby deciding whether the capturing is successful or not. However, due to the existence of noise, interference and the like, the detection amount of the signal on the searching unit is sometimes weakened, and the detection amount of other searching units sometimes has a peak value, so that detection omission or false alarm phenomena are caused. Thus, the navigation receiver should not immediately switch from the acquisition state to the next state after a successful decision on a search unit, but should continue to acknowledge the search unit. That is, a confirmation mechanism needs to be added to the acquisition.

In the related art, the satellite signal capturing and detecting methods with the confirmation mechanism have the problems of counting oscillation, more detection times and incapability of adapting to the dynamic change of the satellite signal quality.

Disclosure of Invention

The present application aims to solve at least one of the above technical problems.

The invention provides a detection method and a detection device applied to satellite signal acquisition, which can at least reduce the detection times.

The present application provides the following technical solutions.

A detection method applied to satellite signal acquisition, comprising:

carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

when the acquisition success of the current search unit in the round of search is judged, a first counter carries out accumulated counting, and when the value of the first counter reaches a preset first maximum value, the counting is stopped, and the successful acquisition of the current satellite signal in the current search unit is indicated;

and when the acquisition failure of the current search unit in the round of search is judged, the second counter carries out accumulated counting, and when the value of the second counter reaches a preset second maximum value, the counting is stopped, and the failure of the current search unit in acquiring the current satellite signal is indicated.

Wherein the method further comprises: and when the current search unit fails to capture, detecting the signal quality change condition of the current search unit according to the detection value obtained by the current search unit in the current search, the detection value obtained by the current search unit in the previous search and the threshold value, and adjusting the first maximum value or the second maximum value according to the signal quality change condition of the current search unit.

Wherein, the detecting the signal quality change condition of the current search unit and adjusting the first maximum value and/or the second maximum value according to the signal quality change condition of the current search unit includes:

verifying whether one of the following relationships is satisfied:

V_n>V_n-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value;

if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value;

wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating the detected value, V, obtained by the current search unit in the previous search_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1Taking a preset initial value, Q is a preset fixed value

Wherein the method further comprises: after the accumulated counting, when the value of the first counter does not reach a preset first maximum value, the first counter keeps a current counting value and indicates that additional searching needs to be continued in a current searching unit; and/or after the accumulated counting, when the value of the second counter does not reach a preset second maximum value, the second counter keeps the current count value and indicates that additional searching needs to be continued in the current searching unit.

Wherein the method further comprises: and when the current search unit fails to acquire the current satellite signal, resetting the values of the first counter and the second counter to initial values and indicating to enter the search of the next search unit.

A detection apparatus for use in satellite signal acquisition, comprising:

the comparator is used for carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

the first counter is used for performing accumulated counting when the comparator judges that the current search unit is successfully acquired, stopping counting when the value after accumulated counting reaches a preset first maximum value, and indicating that the current satellite signal is successfully acquired by the current search unit;

and the second counter is used for performing accumulated counting when the comparator judges that the current search unit fails to acquire the current satellite signal, stopping counting when the value after the accumulated counting reaches a preset second maximum value, and indicating that the current search unit fails to acquire the current satellite signal.

Wherein, still include: the self-adaptive discriminator is used for detecting the signal quality change condition of the current searching unit according to the detection value obtained by the current searching unit in the round of searching, the detection value obtained by the current searching unit in the previous round of searching and the threshold value when the comparator judges that the round of searching fails to be captured in the current searching unit; a first adjuster for adjusting the first maximum value according to a detection result of the adaptive discriminator; and/or a second adjuster for adjusting the second maximum value according to the detection result of the adaptive discriminator.

The adaptive discriminator is specifically configured to:

verifying whether one of the following relationships is satisfied:

V_n>V_n-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value; if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value; wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating the detected value, V, obtained by the current search unit in the previous search_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1Taking a preset initial value, wherein Q is a preset fixed value;

the first adjustor is specifically configured to increase the first maximum value when the adaptive discriminator determines that the signal quality of the current search unit is becoming better; and/or the second adjustor is specifically configured to decrease the second maximum value when the adaptive discriminator determines that the signal quality of the current search unit is deteriorating.

The first counter is further used for keeping a current count value and indicating that additional search needs to be continued in a current search unit when the value after the accumulated count does not reach a preset first maximum value; and/or the second counter is further used for keeping the current count value and indicating that additional search needs to be continued in the current search unit when the value after the accumulated count does not reach the preset second maximum value.

A navigation receiver comprising the above detection apparatus for use in satellite signal acquisition.

The advantages of the present application include at least:

in the embodiment of the invention, a double-counter and threshold judgment mode is introduced into the acquisition detection of the satellite signal, namely, the detection judgment in the acquisition process is realized by combining the threshold and the double counters, each counter only counts when the search acquisition of the current search unit is successful or failed, and the repeated conversion between addition and subtraction is not needed, so that the counting oscillation can be avoided, the acquisition time length is shortened, the detection times are reduced, and the detection performance is improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

FIG. 1 is a schematic diagram of a navigation signal acquisition principle;

FIG. 2 is a flow chart illustrating a process of an M strategy of N in the related art;

FIG. 3 is a schematic diagram of a process flow of Tong detection in the related art;

fig. 4 is a flowchart illustrating a detection method applied to satellite signal acquisition according to a first embodiment;

FIG. 5 is a schematic diagram of an exemplary process flow of a detection method according to an embodiment;

FIG. 6 is a schematic process flow diagram illustrating an embodiment of a detection method according to an embodiment;

fig. 7 is a schematic structural diagram of a detection apparatus applied to satellite signal acquisition according to a third embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

In the related art, the capture algorithm including the confirmation mechanism can be generally classified into two types, a fixed search time method and a variable search time method. The fixed search time method is characterized in that a receiver searches for a preset fixed time on each search unit in total, and then judges whether the acquisition is successful or not according to the multiple search results of the search units in the time period, wherein the judgment represents that the algorithm has an M algorithm of N; the variable search time method is that a receiver may search for an unequal time on each search unit according to a certain rule and in combination with the detection situation at the time, and the overall acquisition performance of the variable search time method generally needs to be better than that of the fixed search time method, which represents that the algorithm is the Tong algorithm.

The following describes a detection strategy of an acquisition algorithm including a confirmation mechanism in the related art.

1, capture detection strategy of M out of N (hereinafter referred to as M strategy of N).

In the M strategy of N, a search unit is searched for N times, and for single judgment, if the detection quantity V exceeds the threshold, the value M of the counter is added with 1. If N searches have been completed and the number of successful times is not less than M, it is considered that acquisition is successful in the frequency interval, otherwise, acquisition is failed, and the flow is shown in fig. 2. The M-of-N strategy is a detection strategy with a fixed number of searches, and thus the detection performance is inferior to the Tong capture detection strategy of the variable search time method.

Tong capture detection strategy.

The Tong capture detection strategy is a linear search method in the form of variable search time, which is basically to add more search time to search units that are difficult to determine whether the signal is captured successfully or not, and the flow is shown in fig. 3. Under the condition of low carrier-to-noise ratio, particularly when the single detection probability is close to 0.5, the K value can repeatedly oscillate between plus 1 and minus 1, so that the detection times are more, and the calculation amount is greatly increased.

An ideal signal acquisition search detection strategy should have two features: lower number of lingers and better detection performance. However, from the above analysis, it can be seen that the above two detection algorithms have two distinct disadvantages: firstly, the detection times are more, and the capture time is long; secondly, the dynamic change of the satellite signal quality cannot be adapted, for example, when the signal of one satellite gradually becomes stronger from weak or weaker from strong, the traditional signal acquisition search detection strategy cannot be adjusted correspondingly.

Therefore, in the satellite signal capturing in the related art, the problems of counting oscillation, large detection times and incapability of adapting to the dynamic change of the satellite signal quality exist, and aiming at the technical problems, the following technical scheme is provided, so that the satellite signal capturing method is less in detection times, can adapt to the dynamic change of the satellite signal quality, and is high in detection performance.

The following describes in detail an implementation of the technical solution of the present application.

Example one

As shown in fig. 4, a detection method applied to satellite signal acquisition may include:

step 401, performing detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

step 402, when the current search unit is successfully acquired in the search round, a first counter performs accumulated counting, and when the value of the first counter reaches a preset first maximum value, the counting is stopped, and the current search unit is indicated to successfully acquire the current satellite signal;

and step 403, judging that the second counter performs accumulated counting when the current search unit fails to acquire the current satellite signal, stopping counting when the value of the second counter reaches a preset second maximum value, and indicating that the current search unit fails to acquire the current satellite signal.

In an implementation manner of this embodiment, when it is determined that the current search unit fails to perform the acquisition, a signal quality change condition of the current search unit may be detected according to a detection value obtained by the current search unit in the current search, a detection value obtained by the current search unit in a previous search, and the threshold, and the first maximum value or the second maximum value may be adjusted according to the signal quality change condition of the current search unit. Therefore, the maximum values of the first counter and the second counter are adjusted by detecting the signal quality change condition, the dynamic change of the satellite signal quality can be adapted, the detection times during satellite signal acquisition are reduced, the detection performance during satellite signal acquisition is improved, and the accuracy of satellite signal acquisition is further improved.

In this embodiment, the specific manner of detecting the signal quality change condition of the current search unit may be various. In one implementation manner, detecting a signal quality change condition of a current search unit, and adjusting the first maximum value and/or the second maximum value according to the signal quality change condition of the current search unit may be implemented as follows:

verifying whether one of the following relationships is satisfied:

Vn>Vn-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value; if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value; wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating the detected value, V, obtained by the current search unit in the previous search_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1A preset initial value is taken, and Q is a preset fixed value. For example, when the preset initial value is 0,when this round of search is the first round of search, V_n-1The value is 0. For example, Q may take on values of 0.3, 0.5, 0.7, and the like. Of course, the initial value or Q may be set to other values according to the application requirements in a specific application. In this way, more search opportunities can be added to the current search unit by increasing the maximum value (namely, the first maximum value) of the first counter when the signal quality is becoming better, and the search opportunities of the current search unit can be reduced by decreasing the maximum value (namely, the second maximum value) of the second counter when the signal quality is becoming worse, so that the detection times can be reduced, the detection efficiency can be improved, and the accuracy of satellite signal acquisition can be improved.

In a specific example of the foregoing implementation manner, the detecting a signal quality change condition of the current search unit, and adjusting the first maximum value and/or the second maximum value according to the signal quality change condition of the current search unit may be implemented as: verifying whether:and isWherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1The detected value obtained by the current search unit in the previous search is shown, if the search is the first search, and there is no 'previous search', V can be taken_n-1Is 0, V_HRepresenting the threshold value. When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value; and if the maximum value is not satisfied, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value. In other words, in satisfyingAnd isIn the case of this relationship, the maximum value of the first counter is adjusted if it is not satisfiedAnd isIn this relationship, the maximum value of the second counter is adjusted. Under the condition, the signal quality change condition of the current search unit can be accurately determined, and the detection efficiency and the satellite signal acquisition accuracy can be better improved. In this embodiment, after the cumulative count, when the value of the first counter does not reach the preset first maximum value, the first counter may keep the current count value and indicate that additional search needs to be continued in the current search unit; and/or after the accumulated counting, when the value of the second counter does not reach a preset second maximum value, the second counter keeps the current count value and indicates that additional searching needs to be continued in the current searching unit. Therefore, the first counter and the second counter are used for controlling the final judgment result detected when the satellite signal on the current search unit is captured, so that the detection efficiency can be improved, and the detection times can be reduced.

In this embodiment, when it is indicated that the current search unit fails to acquire the current satellite signal, the values of the first counter and the second counter may be reset to initial values, and the search of the next search unit may be instructed to be performed. In this way, the next search unit can be shifted to continue the acquisition of the current satellite signal when needed, so as to improve the accuracy and the processing efficiency of the acquisition of the satellite signal.

It should be noted that the types of the first counter and the second counter can be freely selected according to actual needs, and the corresponding count accumulation mode can be adjusted by adopting different types of counters or freely configuring parameters of the counters. In other words, the specific type of the first counter and the second counter, and the specific manner of accumulating the counts, are not limited herein. For example, the first counter and the second counter may both adopt a +1 counter, and the accumulation mode may adopt a "+ 1" mode. Besides, the first counter and the second counter can also adopt binary counters, and the corresponding accumulation counting mode can adopt a binary mode. In practical applications, the maximum value of the first counter (i.e. the first maximum value) and the maximum value of the second counter (i.e. the second maximum value) may be configured at the beginning of the search of the current search unit. Further, the initial value of the first counter (hereinafter referred to as initial value) and the initial value of the second counter (hereinafter referred to as initial value) may be freely set as needed, and for example, the initial value may be 0. In practical applications, the current values of the first counter and the second counter may be reset to the initial value at the beginning of the search of the current search unit.

In this embodiment, the performing a detection decision according to a preset threshold value and a detection value of the current search unit in the round of search may include: comparing a preset threshold value with a detection value of the current search unit in the round of search to perform detection judgment on the current search unit in the round of search; when the detection value of the round of search of the current search unit is not smaller than the threshold value, judging that the round of search is successfully captured in the current search unit; and when the detection value of the round of search of the current search unit is smaller than the threshold value, judging that the round of search fails to be captured in the current search unit.

It should be noted that the threshold value in this embodiment may be an upper limit of a detection value (the detection value may be an amplitude or an energy of a signal obtained when integration is finished after a search is performed on the current search unit, and the energy may be expressed as a square of the amplitude of the signal), and if the detection value in the round of the search of the current search unit is not lower than the threshold value, it indicates that a satellite signal is successfully acquired in the round of the search of the current search unit, and if the detection value is lower than the threshold value, it indicates that a satellite signal is not acquired in the round of the search of the current search unit (i.e., acquisition fails). Different threshold values can be set for different types of satellite signals, and specific values can be set based on actual needs. This is not a limitation herein.

Fig. 5 is an exemplary processing flow of the detection method according to the present embodiment. Therein, an adaptive discriminator is introduced. Specifically, a dual-threshold searcher (corresponding to the detection device applied to satellite signal acquisition hereinafter and not shown in fig. 5) is corresponding to each branch of a pair of I and Q branches, and mainly includes two counters, an amplitude comparator (which is an example of the comparator hereinafter), an adaptive discriminator and two adjusters.

As shown in fig. 5, the exemplary process flow may include: when a receiver starts to search signals in a certain search unit, the values of two counters are preset as initial values; then, a search is performed for the search unit, and after each end of the integration of the signal, the detection value is input to an amplitude comparator, which compares the detection value with a predetermined threshold value (for example, a threshold value V)_t) And comparing to make detection decision.

If the amplitude comparator determines that the acquisition is successful in the current search cell in the round of search, the value of the counter 1 is increased by 1. Then, whether the count value of the counter 1 reaches a preset maximum value is checked to determine whether the current search unit needs to be searched continuously. If the value of the counter reaches the preset maximum value, stopping counting, and indicating that the receiver successfully captures the current satellite signal in the current search unit, and ending the two-dimensional search; and if the value of the counter does not reach the preset maximum value, the counter does not stop counting, and the receiver is indicated to continue additional searching in the current searching unit.

If the amplitude comparator judges that the current search unit in the round of search fails to capture, on one hand, a counter 2 is entered, and the value of the counter 2 is added with 1. Then, it is checked whether the value of the counter 2 reaches a preset maximum value to decide whether the search of the current search unit needs to be continued. If the value of the counter 2 reaches the preset maximum value after the accumulation of the round of search, stopping counting, indicating that the receiver fails to capture in the current search unit, resetting the values of the two counters (namely, the counter 1 and the counter 2) as initial values, turning to the next search unit, continuing to search and executing the processing flow; if the value of the counter 2 after the accumulation of the round of search has not reached the preset maximum value, that is, the counter 2 has not stopped counting, the receiver is instructed to continue the additional search in the current search unit.

If the amplitude comparator determines that the round is the roundAnd on the other hand, the self-adaptive discriminator is entered. The adaptive discriminator detects the signal quality variation of the current search unit (as shown in FIG. 5, the detection value V according to the search of this round_nDetected value V in the previous round of search_n-1Threshold value V_tDetecting the signal quality change condition of the current searching unit), if the self-adaptive discriminator judges that the signal quality of the current searching unit is getting better, entering an adjuster 1, adjusting the maximum value of a counter 1 through a threshold modulator 1, and taking the adjusted maximum value as the basis for judging whether the counter 1 stops at the current time; if the discriminator determines that the signal quality of the current search unit is deteriorating, the method enters the adjuster 2, adjusts the maximum value of the counter 2 through the adjuster 2, and takes the adjusted maximum value as the basis for determining whether the counter 2 stops or not.

Firstly, in the embodiment, a decision manner of a double counter and a threshold is introduced in the acquisition and detection of the satellite signal, that is, the detection decision in the acquisition process is realized by combining the threshold and the double counter, each counter counts only when the search acquisition of the current search unit succeeds or fails, and the repeated conversion between addition and subtraction is not needed, so that the counting oscillation can be avoided, the acquisition time length is shortened, and the detection times are reduced, thereby improving the detection performance. Secondly, in the embodiment, real-time detection of dynamic change of satellite signal quality is added in the detection of satellite signal capture, and the maximum value of each counter is adjusted according to the detection result, so that the search under the current search unit can be added when the satellite signal quality is getting better, and the search under the current search unit is reduced when the satellite signal quality is getting worse, thereby adapting to the dynamic change of the satellite signal quality to adjust the capture strategy of the satellite signal in real time, and achieving the purposes of reducing detection times, shortening capture time and improving detection efficiency and capture efficiency.

The following illustrates a specific implementation of the method of the present embodiment. It should be noted that the following examples are only exemplary implementations of the method of the present embodiment. In practical applications, the specific implementation manner of the method of this embodiment is not limited to this, and other specific implementation manners may be adopted in specific applications in combination with specific application scenarios.

Example 1

As shown in fig. 6, the detection procedure for acquiring satellite signals in this example may include:

step 600, when the receiver starts to search for a signal in a certain search unit, presetting the values of two counters as initial values (for example, presetting M ═ 0 and N ═ 0), and presetting the maximum values of the two counters as a and B, respectively;

step 601, searching in a current searching unit, and inputting a current amplitude Vn into an amplitude comparator after finishing integration of a signal;

step 602, the amplitude comparator compares the current amplitude V_nWith a predetermined amplitude threshold V_HComparing, if the current amplitude V_nGreater than or equal to the amplitude threshold V_HStep 603 is entered; if the current amplitude V is_nLess than an amplitude threshold V_HProceed to step 607;

step 603, if the search acquisition is determined to be successful, the value M of the counter 1 is increased by 1.

Step 604, checking whether the value M of the counter 1 reaches a preset maximum value a to determine whether to continue searching the current search unit; if the value M of the counter 1 reaches the maximum value a after the accumulation through the round of search, go to step 605; if the value M of the counter 1 after the accumulation of the search in this round does not reach the maximum value a, go to step 606;

after this accumulation of the round of searches, the counter 1 stops counting and indicates to the receiver that the current satellite signal has been successfully acquired in the current search unit, and the two-dimensional search is also ended, step 605.

Step 606, after the accumulation of the round of search, the counter 1 has not stopped counting or the counter 2 has not stopped counting, and at this time, the receiver is indicated to need to continue additional search in the current search unit;

step 607, if the current amplitude V is_nLess than an amplitude threshold V_HIf the acquisition of the current search unit fails, the counter 2 is entered, and the value N of the counter 2 is added by 1.

Step 608, checking whether the value N of the counter 2 reaches a preset maximum value B, to determine whether to continue searching the current search unit; if the value N of the counter 2 reaches the maximum value B, go to step 609; if the value N of the counter 2 reaches the maximum value B, go to step 610;

in step 609, the counter 2 stops counting and indicates that the receiver fails to acquire in the current search unit, and goes to the next search unit, and the process returns to step 600, resets the two counters as initial values and repeats the process.

In the above process, if the current amplitude V is_nLess than an amplitude threshold V_tIndicating that the current search unit capture failed, before step 607, the following process may be performed:

step 610, enter the adaptive arbiter, which verifies if the satisfactionAnd isDetecting the signal quality change condition of the current search unit ifAnd isThe adaptive arbiter determines that the signal quality of the current search unit is getting better, then step 611 is entered; otherwise, the adaptive discriminator determines that the signal quality of the current search unit is deteriorating, and then step 612 is entered;

here, where V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Representing the detection value obtained by the current search unit in the previous search, if the search is the first search, and there is no previous search, Vn-1 can be 0, and V can be taken_HRepresenting the threshold value.

Note that, in this example, the judgment condition "And isFor example only, in a specific application, a user may only adjust the signal quality, the acquisition duration, and the like according to different needs of the user.

Step 611, the adjuster 1 adjusts the maximum value a of the counter 1 (for example, adding 1 to the value of the maximum value a), i.e., adds more search opportunities to the current search unit, and meanwhile, uses the adjusted maximum value as the basis for determining whether the counter 1 stops or not next time;

in step 612, the adjustor 2 adjusts the maximum value B of the counter 2 (for example, the value of the maximum value B is decreased by 1), that is, the search opportunity of the current search unit is decreased, and the adjusted maximum value B is used as the basis for currently determining whether the counter 2 is stopped or not.

The method of the present embodiment is applicable to navigation receivers, in particular to baseband digital signal processing modules, and is particularly suitable for acquisition of GPS satellite signals.

Example two

A detection apparatus applied to satellite signal acquisition, as shown in fig. 7, may include:

the comparator 71 is used for carrying out detection judgment according to a preset threshold value and a detection value searched in the round by the current searching unit;

a first counter 72, configured to stop counting when the comparator determines that the current search unit successfully acquires the current satellite signal, and indicate that the current search unit successfully acquires the current satellite signal when a value after the accumulated counting reaches a preset first maximum value;

and a second counter 73, configured to stop counting when the comparator determines that the current search unit fails to acquire the current satellite signal, and indicate that the current search unit fails to acquire the current satellite signal, when a value after the cumulative counting reaches a preset second maximum value.

In an implementation manner of this embodiment, the detecting device may further include: an adaptive discriminator 74, configured to detect a signal quality change condition of the current search unit according to a detection value obtained by the current search unit in the current search, a detection value obtained by the current search unit in a previous search, and the threshold value when the comparator 71 determines that the current search fails in the current search unit; a first adjuster 75 for adjusting the first maximum value according to the detection result of the adaptive discriminator; and/or a second adjuster 76 for adjusting the second maximum value according to the detection result of the adaptive discriminator.

In one implementation, the adaptive arbiter 74 is specifically configured to: verifying whether one of the following relationships is satisfied:

Vn>Vn-1；

V_n>V_n-1and V is_n/V_H>Q；

When the first maximum value is satisfied, judging that the signal quality of the current searching unit is getting better, and increasing the first maximum value; if not, judging that the signal quality of the current searching unit is getting worse, and reducing the second maximum value; wherein, V_nIndicating the detected value, V, obtained by the current search unit during the search round_n-1Indicating the detected value, V, obtained by the current search unit in the previous search_HRepresenting the threshold value; when this round of search is the first round of search, V_n-1A preset initial value is taken, and Q is a preset fixed value. For example, when the preset initial value is 0, V is set to be the first search in the first search round_n-1The value is 0. For example, Q may take on values of 0.3, 0.5, 0.7, and the like. Of course, the initial value or Q may be set to other values according to the application requirements in a specific application. The first adjustor 75 is specifically configured to increase the first maximum value when the adaptive discriminator determines that the signal quality of the current search unit is becoming better; the second adjustor 76 is specifically configured to decrease the second maximum value when the adaptive discriminator determines that the signal quality of the current search unit is deteriorating.

In this embodiment, the first counter 72 may be further configured to keep a current count value and indicate that additional search needs to be continued in the current search unit when the value after the cumulative count does not reach a preset first maximum value; and/or the second counter can be further used for keeping the current count value and indicating that additional search needs to be continued in the current search unit when the value after the accumulated count does not reach the preset second maximum value. Therefore, the final detection judgment result acquired by the current satellite signal can be controlled by the two counters, instead of a mode of repeatedly adding and subtracting one counter, so that the counting oscillation can be avoided, and the detection performance is improved.

In this embodiment, the comparator 71 can be specifically used for: comparing a preset threshold value with a detection value of the current search unit in the round of search to perform detection judgment on the current search unit in the round of search; when the detection value of the round of search of the current search unit is not smaller than the threshold value, judging that the round of search is successfully captured in the current search unit; and when the detection value of the round of search of the current search unit is smaller than the threshold value, judging that the round of search fails to be captured in the current search unit.

It should be noted that the threshold value in this embodiment may be an upper limit of a detection value (the detection value may be an amplitude or an energy of a signal obtained when integration is finished after a search is performed on the current search unit, and the energy may be expressed as a square of the amplitude of the signal), and if the detection value in the round of the search of the current search unit is not lower than the threshold value, it indicates that a satellite signal is successfully acquired in the round of the search of the current search unit, and if the detection value is lower than the threshold value, it indicates that a satellite signal is not acquired in the round of the search of the current search unit (i.e., acquisition fails). Different threshold values can be set for different types of satellite signals, and specific values can be set based on actual needs. This is not a limitation herein.

The detection device of the embodiment has the following advantages: the detection judgment in the capturing process is realized by combining a threshold and the double counters, each counter only counts when the search capturing of the current search unit is successful or failed, and the repeated conversion between addition and subtraction is not needed, so that the counting oscillation can be avoided, the capturing time is shortened, the detection times are reduced, and the detection performance is further improved. Then, the detection apparatus of this embodiment further includes an adaptive discriminator, and the adaptive discriminator detects dynamic changes of the satellite signal quality in real time and adjusts the maximum value of each counter accordingly, so that it is possible to add searches in the current search unit when the satellite signal quality is getting better, reduce searches in the current search unit when the satellite signal quality is getting worse, and adjust the acquisition policy of the satellite signal in real time in accordance with the dynamic changes of the satellite signal quality, thereby achieving the purposes of reducing the detection times, shortening the acquisition time, and improving the detection efficiency and the acquisition efficiency.

In practical applications, the detection device applied to the satellite signal acquisition of the embodiment may be implemented by or disposed in a navigation receiver. In one implementation, the detection device may be implemented by a baseband digital signal processing module of the navigation receiver. The comparator 71, the first counter 72, the second counter 73, the adaptive discriminator 74, the first adjustor 75, and the second adjustor 76 may be software, hardware, or a combination of the two. In one implementation, the detection apparatus may be disposed in or implemented as the detection decider in fig. 1.

Other technical details of the present embodiment may refer to the first embodiment.

EXAMPLE III

The application also provides a navigation receiver, which comprises the detection device applied to satellite signal acquisition. Specific technical details can be found in reference to the first embodiment and the second embodiment.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.