阅读说明：本技术 一种基于tws雷达数据处理系统的时钟校准方法及系统 (Clock calibration method and system based on TWS radar data processing system ) 是由 唐伟 侯昌波 郝育松 赵冉宇 邱俊 张曌 王炘 于 2020-04-30 设计创作，主要内容包括：本发明公开了一种基于TWS雷达数据处理系统的时钟校准方法,包括：解析勤务报报文,得到报文内的时间和扇区号,若报文内容不含时间,则采用本地时间代替；分析扇区号,判断扇区号是否为0,若是,则在周期计数器上加1；若否,则将本次获取的扇区时间与上次该扇区时间计算时间差；判断时间差是否小于设定阈值；若是,则采用上次计算的雷达旋转周期；若否,则进行一维估值滤波；将滤波后的周期值填充到周期时间扇区队列中；以滤波后的周期值为基准,向前外推扇区总数的25％个扇区,并填入扇区时间内。该方法采用分扇区时钟估值校准方法,实现了自适应扇区时钟校准,运算量较小,可以避免因为本地时间的不一致导致产生虚警和漏警的情况。(The invention discloses a clock calibration method based on a TWS radar data processing system, which comprises the following steps: analyzing the service report message to obtain the time and sector number in the message, and if the message content does not contain time, replacing the time with local time; analyzing the sector number, judging whether the sector number is 0, and if so, adding 1 to the cycle counter; if not, calculating the time difference between the sector time acquired this time and the sector time acquired last time; judging whether the time difference is smaller than a set threshold value or not; if so, adopting the radar rotation period calculated last time; if not, performing one-dimensional estimation filtering; filling the filtered period value into a period time sector queue; based on the filtered period value, 25% of the total number of sectors are extrapolated forward and filled in the sector time. The method adopts a sector clock estimation calibration method, realizes self-adaptive sector clock calibration, has small calculation amount, and can avoid the conditions of false alarm and false alarm leakage caused by inconsistent local time.)

1. A clock calibration method based on a TWS radar data processing system is characterized by comprising the following steps:

acquiring a service report message;

analyzing the service report message to obtain the time and the sector number in the message, and if the message content does not contain time, replacing the time with local time;

judging whether the sector number is larger than the maximum value of a set sector number or whether the sector number is equal to the last sector number;

if yes, the calculation is finished;

if not, judging whether the sector number is equal to 0;

if the sector number is equal to 0, adding 1 to the cycle counter;

if the sector number is not equal to 0, calculating the time difference between the sector time acquired this time and the previous sector time, wherein the time difference is the corresponding radar rotation period of the sector;

judging whether the time difference is smaller than a set threshold value or not;

if so, adopting the radar rotation period calculated last time;

if not, performing one-dimensional estimation filtering to obtain a filtered period value;

filling the filtered period value into a period time sector queue;

based on the filtered period value, 25% of the total number of sectors are extrapolated forward and filled in the sector time.

2. The TWS radar data processing system-based clock calibration method of claim 1, further comprising: and acquiring a trace target of the target from the front end of the radar, and performing clock calibration on the trace target.

3. The clock calibration method for a TWS-based radar data processing system of claim 2, wherein the specific step of calibrating the clock of the trace object comprises:

calculating a sector where a trace point target is located;

acquiring the sector time and first discrete azimuth information of the current sector from the time sector queue;

acquiring the sector time and second discrete azimuth information of the next sector from the time sector queue;

calculating the angle corresponding to the current sector and the angle corresponding to the next sector according to the first discrete azimuth information and the second discrete azimuth information;

and calculating the time of the trace point through linear interpolation to obtain the calibrated trace point time.

4. The TWS radar data processing system-based clock calibration method of claim 1, wherein the one-dimensional filter includes an averaging filter, a sliding filter, and a kalman filter.

5. The clock calibration method for a TWS radar-based data processing system according to claim 1, wherein the time accuracy of the local time is ≧ 1 millisecond.

6. A clock calibration system based on a TWS radar data processing system is characterized by comprising a service report message acquisition module, a service report message analysis module and a clock processing module,

the service report message acquisition module is used for acquiring a service report message;

the service report message analysis module is used for analyzing the service report message to obtain the time and the sector number in the message, and if the message content does not contain time, local time is adopted for replacement;

the clock processing module is used for analyzing the sector number of the current time and judging whether the sector report is a positive north sector report or a common sector report, if the sector report is the positive north sector, 1 is added to a period counter, if the sector report is the common sector, the time difference between the sector time acquired this time and the sector time of the last time is calculated, and the time difference is the corresponding radar rotation period of the current sector; judging whether the time difference is smaller than a set threshold value or not; if so, adopting the radar rotation period calculated last time; if not, performing one-dimensional estimation filtering to obtain a filtered period value; filling the filtered period value into a period time sector queue; based on the filtered period value, 25% of the total number of sectors are extrapolated forward and filled in the sector time.

7. The clock calibration system based on the TWS radar data processing system of claim 6, wherein the system further comprises a trace-by-point clock processing module for acquiring trace-by-point targets of the targets from the radar front end and performing clock calibration on the trace-by-point targets.

8. The clock calibration system based on the TWS radar data processing system according to claim 7, wherein the specific processing method of the trace-by-point clock processing module comprises the following steps: calculating a sector where a trace point target is located; acquiring the sector time and first discrete azimuth information of the current sector from the time sector queue; acquiring the sector time and second discrete azimuth information of the next sector from the time sector queue; calculating the angle corresponding to the current sector and the angle corresponding to the next sector according to the first discrete azimuth information and the second discrete azimuth information; and calculating the time of the trace point through linear interpolation to obtain the calibrated trace point time.

9. The TWS radar data processing system based clock calibration system of claim 6 wherein the one dimensional filter comprises an averaging filter, a sliding filter and a Kalman filter.

10. The clock calibration system based on a TWS radar data processing system of claim 6, wherein the time precision of the local time is ≧ 1 millisecond.

Technical Field

The invention relates to the technical field of radar data processing, in particular to a clock calibration method and system based on a TWS radar data processing system.

Background

A Scanning and Tracking (TWS) radar data processing system continuously scans through a radar antenna to obtain the position and the velocity vector of a target, and is a common processing framework of a route radar and an airport radar. However, due to the inherent characteristics of the turntable, including static errors, dead weight, inertial load, wind load, temperature difference, uneven foundation subsidence and the like generated in the processes of processing, installation and adjustment, structural deformation is caused, so that the period of the turntable is inconsistent with the difference of the use time, the use frequency and the use environment, the rotating speed of the turntable is often unstable in the field, and the period of the turntable is unstable. In the shore-based monitoring radar system, under the adverse working condition of strong wind, the error of the adjacent period can reach 3%, and inevitable error is brought to a rear-end data processing system.

The traditional TWS radar data processing system based on the constant rotating speed or the cycle as the reference has the following obvious disadvantages:

(1) in the process of track starting, because the rotating speed is unstable and a common mode is added, the system can calculate smaller or larger speed for a detected real target because the time is inaccurate, so that the speed exceeds a speed threshold, and the track cannot be correctly started; in a three-point track initiation system, a wrong large acceleration is calculated, so that track initiation failure is caused; in systems that start with heading limits, this can also result in the generation of an incorrect angular velocity, resulting in a failed track start. In the process of track initiation, the system can wrongly calculate wrong kinematic parameters related to time, so that the track initiation fails; false targets may also be generated due to incorrect timing, resulting in false alarms and false alarms.

(2) In the process of target tracking, the error estimation of the motion state can occur, so that the target is lost; generating wrong kinematic parameters such as speed, course, acceleration and the like, and generating wrong parameters for an air traffic control automatic system, an early warning system and the like, so that the automatic system generates wrong judgment, and a back end generates wrong decisions.

(3) In the process of target management, due to wrong rotation speed cycles, targets which are normally tracked are lost for multiple times, the system deletes the flight path, and the target flight path is lost, which is fatal to an automatic system and a decision-making system.

Disclosure of Invention

Aiming at the defects in the prior art, the embodiment of the invention provides a clock calibration method and a clock calibration system based on a TWS radar data processing system.

In a first aspect, a clock calibration method based on a TWS radar data processing system provided in an embodiment of the present invention includes:

acquiring a service report message;

analyzing the service report message to obtain the time and the sector number in the message, and if the message content does not contain time, replacing the time with local time;

judging whether the sector number is larger than the maximum value of a set sector number or whether the sector number is equal to the last sector number;

if the sector number is larger than the maximum value of the set sector number or the sector number is equal to the last sector number, the calculation is finished;

if the sector number is smaller than the maximum value of the set sector number or the sector number is not equal to the previous sector number, judging whether the sector number is equal to 0 or not;

if the sector number is equal to 0, the sector number is positive north, and 1 is added to the cycle counter;

if the sector number is not equal to 0, indicating that the sector number is a common sector report, calculating a time difference between the sector time acquired this time and the sector time of the last time, wherein the time difference is the corresponding radar rotation period of the sector;

judging whether the time difference is smaller than a set threshold value or not;

if so, adopting the radar rotation period calculated last time;

if not, performing one-dimensional estimation filtering to obtain a filtered period value;

filling the filtered period value into a period time sector queue;

based on the filtered period value, 25% of the total number of sectors are extrapolated forward and filled in the sector time.

In a second aspect, an embodiment of the present invention provides a clock calibration system based on a TWS radar data processing system, including: a service report message acquisition module, a service report message analysis module and a clock processing module,

the service report message acquisition module is used for acquiring a service report message;

the service report message analysis module is used for analyzing the service report message to obtain the time and the sector number in the message, and if the message content does not contain time, local time is adopted for replacement;

the clock processing module is used for analyzing the sector number of the current time and judging whether the sector report is a positive north sector report or a common sector report, if the sector report is the positive north sector, 1 is added to a period counter, if the sector report is the common sector, the time difference between the sector time acquired this time and the sector time of the last time is calculated, and the time difference is the corresponding radar rotation period of the current sector; judging whether the time difference is smaller than a set threshold value or not; if so, adopting the radar rotation period calculated last time; if not, performing one-dimensional estimation filtering to obtain a filtered period value; filling the filtered period value into a period time sector queue; based on the filtered period value, 25% of the total number of sectors are extrapolated forward and filled in the time sector time.

The invention has the beneficial effects that:

according to the clock calibration method and system based on the TWS radar data processing system, provided by the invention, the sector service report is started, the sector clock estimation calibration method is adopted, the self-adaptive sector clock calibration is realized, the calculation amount is small, the engineering realization is easy, and the situations of false alarm and false alarm leakage caused by the inconsistency of local time can be avoided.

In addition, the trace clock uses the calibration time, and the problems of trace clock message loss and trace message inaccuracy are solved. The problem of data processing failure caused by the loss of message time to time or the error of message time can be avoided, the requirement on the rotating speed precision of the rotary table can be reduced, and even a data processing system of a non-uniform rotary table can be used.

Drawings

In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

Fig. 1 is a flowchart illustrating a clock calibration method based on a TWS radar data processing system according to a first embodiment of the present invention;

fig. 2 shows a detailed flowchart of step S13 in fig. 1;

fig. 3 shows a block diagram of a clock calibration system based on a TWS radar data processing system according to a second embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

As used in this specification and the appended claims, the term "if" may be interpreted contextually as "when", "upon" or "in response to a determination" or "in response to a detection". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the invention pertains.

Referring to fig. 1 and 2, a clock calibration method for a TWS-based radar data processing system according to a first embodiment of the present invention includes:

s1, acquiring service report messages, for example: asterix Cat002, Cat 003, MH4008 Cat 002.

S2, analyzing the service report message to obtain the time T in the message_kAnd sector number Sec_kIf the message content does not contain time, local time is adopted for replacing the message content, and the local time precision is more than or equal to 1 millisecond.

S3, judging the sector number Sec_kWhether or not it is larger than the maximum value Sec of the set sector number_MaxOr judging the sector number Sec_kWhether it is equal to the last sector number Sec_k-1。

S4 sector number Sec_kGreater than the maximum value Sec of the set sector number_MaxOr sector number Sec_kIs equal to the last sector number Sec_k-1And ending the calculation.

S5 sector number Sec_kLess than the maximum value Sec of the set sector number_MaxOr sector number Sec_kIs not equal to the last sector number Sec_k-1Then, the sector number Sec is determined_kWhether or not it is equal to 0.

S6 sector number Sec_kEqual to 0, it means a true north sector is reported, and 1 is added to the cycle counter.

S7 sector number Sec_kIf not equal to 0, the sector is indicated to be a common sector report, and the sector time T acquired this time is reported_k ^SecAnd last time of the sector_k-1 ^SecCalculating the time difference P_k ^Sec＝|T_k-1 ^Sec-T_k ^SecL, the time difference P_k ^SecThe radar rotation period of the corresponding local sector.

S8, judging the time difference P_k ^SecWhether the threshold is smaller than the set threshold, the set threshold is generally smaller, such as 1 per thousand-1% multiplied by the radar period or 1 per thousand-1% multiplied by the last timeThe calculated radar period (i.e.:)。

s9, if yes, the last calculated radar rotation period, namely P, is adopted_k ^Sec＝P_k-1 ^Sec。

S10, if not, one-dimensional estimation filtering is carried out to obtain a filtered period value P_k ^Sec,f. The one-dimensional estimation filtering can adopt one-dimensional filters such as an average filter, a sliding filter, a Kalman filter and the like.

S11, filtering the period value P_k ^Sec,fFill into Period time sector queue Period]＝P_k ^Sec,f。

S12, calculating the value of the period P by filtering_k ^Sec,fFor reference, 25% of the total number of sectors are extrapolated forward (8 sectors if the total number of sectors is 32, 32 sectors if the total number of sectors is 256)And fills in the Time sector (Time Sec)]) And (4) the following steps.

Through the steps, the sector service report is started, the sector clock estimation calibration method is adopted, the self-adaptive sector clock calibration is realized, the calculation amount is small, the engineering realization is easy, and the situations of false alarm and false alarm leakage caused by the inconsistency of local time can be avoided.

In the present embodiment, it is assumed that the radar detects a trace-point target P_m(ρ_m,θ_m) And the time T attached to the point_mAt this time, the system does not use the time T_mThe method further includes a step S13 of performing clock calibration on the trace object.

The step of calibrating the clock of the trace point target comprises the following steps:

s131, passingAnd calculating the sector where the trace point target is located.

S132: from Time sector queue Time Sec_now]Obtaining the sector time T of the current sector₁，T₁＝Time[Sec_now]And first discrete orientation information Sec₁。

133: from the Time sector queue Time [ (Sec)_now+1+Sec_Max)％Sec_Max]To obtain the sector time T of the next sector₂，T₂＝Time[(Sec_now+1+Sec_Max)％Sec_Max]And second discrete orientation information Sec₂。

S134: calculating the corresponding angle of the current sector according to the first discrete azimuth information and the second discrete azimuth informationAngle corresponding to next sectorThe calculation formulas are respectively

S135: and calculating the time of the trace point through linear interpolation to obtain the calibrated trace point time. The calculation formula is as follows:wherein, T_mThe trace point time required to be obtained; theta_mA point trace azimuth obtained for the measurement; t is₂Sector time of the next sector; t is₁The sector time of the current sector.

Through the steps, the calibration time is used in the trace clock processing process, and the problems of trace clock message loss and trace message inaccuracy are solved. The requirement on the rotating speed precision of the rotary table is reduced, the rotary table is continuously and seamlessly switched from 3 revolutions per minute to 15 revolutions per minute, the system stably operates, and even in a 15 revolutions per minute working mode, under the condition that the true north is used as the starting point of the period calculation, the system still normally works without errors after 10% deviation. The problem of data processing failure caused by the loss of message time to time or the error of message time can be avoided, the requirement on the rotating speed precision of the rotary table can be reduced, and even a data processing system of a non-uniform rotary table can be used.

According to the clock calibration method based on the TWS radar data processing system, the sector service report is started, the sector clock estimation calibration method is adopted, the requirement for self-adaptive clock calibration in data processing of the TWS system is met, the calculation amount is small, engineering implementation is easy, and the situations of false alarm and false alarm leakage caused by inconsistency of local time can be avoided. In addition, the trace clock uses the calibration time, and the problems of trace clock message loss and trace message inaccuracy are solved. The problem of data processing failure caused by the loss of message time to time or the error of message time can be avoided, the requirement on the rotating speed precision of the rotary table can be reduced, and even a data processing system of a non-uniform rotary table can be used.

In the first embodiment, a clock calibration method based on the TWS radar data processing system is provided, and correspondingly, the application also provides a clock calibration system based on the TWS radar data processing system. Please refer to fig. 3, which is a schematic structural diagram of a clock calibration system based on a TWS radar data processing system according to a second embodiment of the present invention. Since the apparatus embodiments are substantially similar to the method embodiments, they are described in a relatively simple manner, and reference may be made to some of the descriptions of the method embodiments for relevant points. The device embodiments described below are merely illustrative.

As shown in fig. 3, there is a block diagram illustrating a clock calibration system based on a TWS radar data processing system according to a second embodiment of the present invention, where the system includes: the system comprises a service report message acquisition module, a service report message analysis module and a clock processing module, wherein the service report message acquisition module is used for acquiring a service report message; the service report message analysis module is used for analyzing the service report message to obtain the time and the sector number in the message, if the message content does not contain time, local time is adopted for substitution, and the local time precision is more than or equal to 1 millisecond; the clock processing module is used for analyzing the sector number of the current time and judging whether the sector report is a positive north sector report or a common sector report, if the sector report is the positive north sector, 1 is added to a period counter, if the sector report is the common sector, the time difference is calculated between the sector time acquired this time and the previous sector time, and the time difference is the corresponding radar rotation period of the current sector; judging whether the time difference is smaller than a set threshold value or not; if so, adopting the radar rotation period calculated last time; if not, performing one-dimensional estimation filtering to obtain a filtered period value; filling the filtered period value into a period time sector queue; based on the filtered period value, 8 sectors are extrapolated forward and filled into the time sector queue. The one-dimensional filter includes an average filter, a sliding filter, and a kalman filter.

In this embodiment, the system further includes a trace point clock processing module, where the trace point clock processing module is configured to obtain a trace point target of the target from the radar front end; and carrying out clock calibration on the trace target.

The specific process of the trace clock processing module for clock calibration comprises the following steps: calculating a sector where a trace point target is located; acquiring the sector time and first discrete azimuth information of the current sector from the time sector queue; acquiring the sector time and second discrete azimuth information of the next sector from the time sector queue; calculating the angle corresponding to the current sector and the angle corresponding to the next sector according to the first discrete azimuth information and the second discrete azimuth information; and calculating the time of the trace point through linear interpolation to obtain the calibrated trace point time.

The clock calibration system based on the TWS radar data processing system provided by the embodiment starts from the sector service report, adopts the sub-sector clock estimation calibration method, meets the requirement of self-adaptive clock calibration in data processing of the TWS system, has small calculation amount, is easy for engineering realization, and can avoid the situations of false alarm and alarm leakage caused by inconsistent local time. In addition, the trace clock uses the calibration time, and the problems of trace clock message loss and trace message inaccuracy are solved. The problem of data processing failure caused by the loss of message time to time or the error of message time can be avoided, the requirement on the rotating speed precision of the rotary table can be reduced, and even a data processing system of a non-uniform rotary table can be used.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.