Integrated waveform generation method for secondary wind sounding radar

Abstract

The present invention discloses a method for generating an integrated waveform of a secondary wind sounding radar. In this method, the ground radar interrogation waveform consists of a command waveform and a detection waveform, wherein the command waveform is used to transmit meteorological type information and control information, and the detection waveform is used to detect the motion state of an air balloon; the command waveform is formed by carrier modulation of a start pulse, a stop pulse and a plurality of information pulses, and the detection waveform includes a plurality of linear frequency modulation waveforms repeated in a time period; the sonde receives the detection waveform emitted by the ground radar, and stores it according to the time repetition period, and uses amplitude modulation or phase modulation to load the meteorological type data to be transmitted onto the detection waveform to form a response waveform, which is then sent to the ground radar. Compared with the prior art, the present invention improves the reliability of meteorological detection information transmission and the accuracy of detection data, and improves the control capability of the sonde.

Description

Technical Field

[0001] The invention relates to the field of radar, and in particular to an integrated waveform generation method for a secondary wind sounding radar. Background Art

[0002] The correctness of meteorological observation directly affects the normal operation of the entire national economy. Meteorological instruments serve important national departments such as meteorology, environmental protection, transportation, and national defense. They also play a huge role in disaster forecasting and provide strong protection for the safety of people's property. The secondary wind sounding radar system is an important device for realizing high-altitude meteorological detection. It consists of a ground radar and a sounding balloon carrying a sounding instrument. The sounding instrument is the most important instrument for high-altitude meteorological detection. It is carried to high altitudes by a sounding balloon. It uses radio telemetry and positioning methods to comprehensively detect meteorological elements such as atmospheric temperature, relative humidity, air pressure, wind direction and wind speed within a range of 30 kilometers from the ground to high altitude, providing a basis for weather analysis by the meteorological department. It is an important part of comprehensive meteorological detection and plays an irreplaceable role in national defense construction and economic construction.

[0003] In the prior art, the ground radar of the secondary wind sounding radar system triggers the airborne sonde to send back a "reply signal" containing a sounding code by sending a detection waveform. However, due to the lack of communication methods and control means between the ground radar and the airborne sonde, the ground radar cannot control the working state of the airborne sonde, making it "out of control"; the detection waveform emitted by the ground radar is a narrowband signal, the detection waveform carries little energy, and has weak anti-interference ability, resulting in a low signal-to-noise ratio received by the airborne sonde, making it difficult for the airborne sonde to respond to the "inquiry signal" of the ground radar in time, and easily resulting in the phenomenon of "there is a question but no answer"; the narrowband signal also makes it difficult for the sonde to accurately capture the rising edge of the ground radar "inquiry signal", and cannot trigger the "reply signal" in time, resulting in inaccurate transmission delay measurement between the "inquiry signal" and the "reply signal", reducing the ranging accuracy. Therefore, the ground radar cannot grasp the working state of the sonde, and the detection signal and the reply signal have weak anti-interference ability, which leads to poor reliability of meteorological detection data transmission and low detection data accuracy.

[0004] How to improve the signal transmission capability of the secondary wind sounding radar system, enhance the reliability of meteorological detection data transmission, and improve the accuracy of detection data are difficult problems that technical personnel in this field need to solve. Summary of the invention

[0005] The purpose of the present invention is to disclose a method for generating an integrated waveform of a secondary wind sounding radar, so as to improve the signal transmission capability, enhance the reliability of meteorological detection data transmission, and improve the detection accuracy. In order to achieve the purpose of the present invention, the present invention provides a method for generating an integrated waveform of a secondary wind sounding radar. In this method, a ground radar interrogation waveform and a radiosonde response waveform are included; wherein,

[0006] The ground radar interrogation waveform consists of a command waveform and a detection waveform. The command waveform is used to transmit meteorological type information and control information, and the detection waveform is used to detect the motion state of the balloon in the air. The command waveform is formed by carrier modulation of a start pulse, a stop pulse and a plurality of information pulses, and the detection waveform includes a plurality of linear frequency modulation waveforms repeated in a time period. The ground radar interrogation waveform is expressed as:

[0007] ;

[0008] in, Indicates the start pulse, Indicates the termination pulse, Represents information pulse, represents the time interval between the information pulse and the start pulse, represents the time interval between the end pulse and the start pulse, represents the time interval between the first linear frequency modulation waveform and the start pulse, Indicates the number of linear frequency modulation waveforms, represents the time repetition period of the linear frequency modulation waveform, Indicates the frequency modulation slope; and Indicates the carrier frequency;

[0009] The sonde forms a response waveform by a store-modulate-forward method. Specifically, the sonde receives the detection waveform emitted by the ground radar and stores it according to the time repetition period. The sonde prepares the meteorological type data to be transmitted according to the received command waveform, reads the detection waveform according to the time repetition period, and uses amplitude modulation or phase modulation to load the meteorological type data to be transmitted onto the detection waveform to form a response waveform, which is then sent to the ground radar.

[0010] Furthermore, in the technical solution disclosed in the present invention, the information pulse It is composed of multiple wide pulses and narrow pulses with the same time intervals. The wide pulses and narrow pulses represent digital information 1 and 0 respectively. Pulse width modulation is used to load the information onto the carrier to form a command waveform modulation signal.

[0011] Further, in the technical solution disclosed in the present invention, the radar detection waveform has different waveforms in different working modes:

[0012] In the general working mode, the radar detection waveform has a frame length of 1920 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 60 μs;

[0013] In the long-range working mode, the radar detection waveform has a frame length of 3840 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 120 μs or 64 linear frequency modulation waveforms with a repetition period of 60 μs;

[0014] In the short-range working mode, the radar detection waveform has a frame length of 960 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 30 μs or 16 linear frequency modulation waveforms with a repetition period of 60 μs.

[0015] Furthermore, in the technical solution disclosed in the present invention, the instruction waveform is also provided with a check bit pulse , set between the last information pulse and the termination pulse, the check bit pulse With the start pulse The time interval is , the time width is ,in, It is the total number of 0s in the meteorological type information and control information to be transmitted in the command waveform.

[0016] Furthermore, in the technical solution disclosed in the present invention, the timing of transmitting the sonde response waveform is: after the sonde receives the ground radar interrogation waveform, it delays for 2060 μs and then transmits the sonde response waveform.

[0017] Furthermore, in the technical solution disclosed in the present invention, the time repetition period of the linear frequency modulation waveform is Includes the waveform sending period and the waveform stopping period.

[0018] Preferably, in the technical solution disclosed in the present invention, the carrier frequency and Works in the microwave L band.

[0019] Preferably, in the technical solution disclosed in the present invention, the information pulse It is composed of 8 wide pulses and narrow pulses with the same time intervals, carrying 8 bits of binary information, and the data combination state of the 8 bits of information represents the meteorological type information and control information to be transmitted.

[0020] Preferably, in the technical solution disclosed in the present invention, the information pulse The pulse width of the wide pulse is 2μs, and the pulse width of the narrow pulse is 1μs.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The integrated design of communication and detection waveforms is realized, which improves the control capability of the sonde

[0023] In the technical solution disclosed in the present invention, an integrated design of command waveform and detection waveform is adopted, and while detecting the motion state of the sounding balloon, meteorological type selection information and control instructions are transmitted to the sonde. Through the control instruction transmission, the channel gain, sleep time and code rate of the response waveform of the sonde are reasonably controlled, the working state of the sonde is scientifically controlled, the hardware implementation complexity is reduced, and the meteorological type information can be selectively transmitted according to actual needs, which greatly reduces the signal processing complexity of the sonde, significantly increases the sleep time of the sonde, and thus can greatly reduce the power consumption of the sonde, which is conducive to extending the air working time of the sonde. In the prior art, the secondary wind sounding radar system lacks the communication method and control means between the ground radar and the air sonde, and the ground radar cannot control the working state of the air sonde, making it in an "out of control" state. Therefore, compared with the prior art, the present invention greatly realizes the integrated design of communication and detection waveforms, improves the control ability of the sonde, and reduces the power consumption of the sonde and increases the air working time of the sonde by reasonably controlling the working state of the sonde.

[0024] (2) Improved the received signal-to-noise ratio of the detection waveform, reduced the time capture requirements, and improved the detection accuracy

[0025] In the technical solution disclosed in the present invention, the ground radar uses a linear frequency modulation signal to form a detection waveform. The linear frequency modulation signal has a large time-bandwidth product and a strong anti-interference ability. The airborne sonde can process the gain by pulse compression, which can significantly improve the received signal-to-noise ratio, and can ensure that the airborne sonde responds to the "inquiry signal" of the ground radar in a timely manner, and transmits the meteorological detection signal to the ground in real time, avoiding the phenomenon of "no answer to the question". Further, in the technical solution disclosed in the present invention, the pulse accumulation characteristics of the multiple linear frequency modulation signals contained in the detection waveform enable the sonde to greatly improve the signal-to-noise ratio of the received ground radar detection signal, accurately capture the rising edge of the ground radar "inquiry signal", and timely trigger the "response signal", thereby improving the ranging accuracy. Therefore, compared with the prior art, the technical solution disclosed in the present invention improves the received signal-to-noise ratio of the detection waveform received by the sonde, reduces the time capture requirements, and improves the detection accuracy.

[0026] (3) Improved the anti-interference capability of meteorological detection signal transmission

[0027] In the technical solution disclosed in the present invention, the sounding instrument adopts the storage-modulation-forwarding method to form a response waveform, which not only eliminates the traditional resonance module, phase shift module, etc., reduces the cost, power consumption and volume, and improves the endurance time of the sounding instrument; at the same time, it also makes the sounding instrument response waveform and the ground radar detection waveform have good autocorrelation characteristics. By utilizing this autocorrelation, the channel noise interference can be effectively resisted; further, the linear frequency modulation waveform contained in the response waveform enhances the signal-to-noise ratio of the response signal received and processed by the ground radar, and the pulse compression and pulse accumulation processing can greatly improve the signal-to-noise ratio of the weak response signal of the sounding instrument received by the ground radar; further, the response waveform is formed by secondary modulation of the phase or amplitude of the linear frequency modulation pulse, that is, the linear frequency modulation signal can be used to transmit information; the ground radar can use pulse compression to obtain code element information to demodulate the pulse signal, and use the demodulated signal for coherent accumulation to further improve the signal-to-noise ratio. Pulse accumulation can also improve the signal-to-noise ratio of the signal, which is beneficial to improving the reliability of meteorological detection information transmission, and is also beneficial to improving the ranging accuracy and angle measurement accuracy of the ground radar. Therefore, compared with the prior art, the technical solution disclosed in the present invention reduces the complexity of equipment and improves the reliability of meteorological detection information transmission.

[0028] Other advantages and features of the present invention will be reflected in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] none DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0031] In the prior art, the ground radar of the secondary wind sounding radar system triggers the airborne sonde to send back a "reply signal" containing a sounding code by sending a detection waveform, but there is a lack of communication methods and control means between the ground radar and the airborne sonde, and the ground radar cannot control the working state of the airborne sonde, causing it to be in an "out of control" state; the detection waveform emitted by the ground radar is a narrowband signal, the detection waveform carries little energy and has weak anti-interference ability, resulting in a low signal-to-noise ratio for the airborne sonde, which is prone to the phenomenon of "questions without answers"; it is difficult to accurately capture the rising edge of the ground radar "interrogation signal" and cannot trigger the "reply signal" in time, resulting in inaccurate measurement of the transmission delay between the "interrogation signal" and the "reply signal", reducing the ranging accuracy; the ground detection waveform and the sounding instrument reply waveform are unrelated to each other and are two completely different waveforms, which increases the complexity of the ground radar in processing the sounding instrument signal, and the anti-interference ability of the reply waveform in the existing system results in a low reception signal-to-noise ratio for the reply waveform received by the ground radar, and even the phenomenon of being unable to extract meteorological information, making it difficult to ensure the reliability of meteorological detection information transmission.

[0032] In order to solve the problems existing in the prior art, the wind sounding radar system principle is deeply studied, and the integrated waveform generation method of the wind sounding radar system is innovated. On this basis, the embodiment of the present invention discloses a secondary wind sounding radar integrated waveform generation method. In this method, a ground radar interrogation waveform and a sounding instrument response waveform are included; wherein the ground radar interrogation waveform is composed of a command waveform and a detection waveform; further, the command waveform is used to transmit meteorological type information and control information, and the detection waveform is used to detect the movement state of the balloon in the air; the command waveform is formed by a start pulse, an end pulse and a plurality of information pulses through carrier modulation, and the detection waveform includes a plurality of linear frequency modulation waveforms repeated in a time period; the ground radar interrogation waveform is expressed as:

[0033] ;

[0034] in, Indicates the start pulse, Indicates the termination pulse, Represents information pulse, represents the time interval between the information pulse and the start pulse, represents the time interval between the end pulse and the start pulse, represents the time interval between the first linear frequency modulation waveform and the start pulse, Indicates the number of linear frequency modulation waveforms, Indicates the time repetition period of the linear frequency modulation waveform, including the waveform sending period and the waveform stopping period. Indicates the frequency modulation slope; and represents the carrier frequency; typically, the carrier frequency and Works in the microwave L band.

[0035] Furthermore, in the technical solution disclosed in the embodiment of the present invention, the sonde forms a response waveform by a store-modulate-forward method. Specifically, the sonde receives the detection waveform emitted by the ground radar and stores it according to the time repetition period, prepares the meteorological type data to be transmitted according to the received command waveform, reads the detection waveform according to the time repetition period, and uses amplitude modulation or phase modulation to load the meteorological type data to be transmitted onto the detection waveform to form a response waveform, which is then sent to the ground radar.

[0036] In the technical solution disclosed in the embodiment of the present invention, the command waveform and the detection waveform are integrated to transmit the meteorological type selection information and control instructions to the sonde while detecting the motion state of the sounding balloon. Through the control instruction transmission, the channel gain, sleep time and code rate of the response waveform of the sonde are reasonably controlled, the working state of the sonde is scientifically controlled, the functional mode design is saved, the hardware implementation complexity is reduced, and the meteorological type information can be selectively transmitted according to actual needs, which greatly reduces the signal processing complexity of the sonde and significantly increases the sleep time of the sonde, thereby greatly reducing the power consumption of the sonde, which is conducive to extending the air working time of the sonde. In the prior art, the ground radar of the secondary wind sounding radar system triggers the air sonde to send back the "answer signal" containing the sounding code by sending the detection waveform, but there is a lack of communication mode and control means between the ground radar and the air sonde, and the ground radar cannot control the working state of the air sonde, making it in an "out of control" state.

[0037] Furthermore, in the technical solution disclosed in the embodiment of the present invention, the information pulse It is composed of multiple wide pulses and narrow pulses with the same time interval, and the wide pulses and narrow pulses represent digital information 1 and 0 respectively. The information is loaded onto the carrier by pulse width modulation to form a command waveform modulation signal. Typically, the information pulse The pulse width of the wide pulse is 2μs, and the pulse width of the narrow pulse is 1μs.

[0038] Furthermore, in the technical solution disclosed in the embodiment of the present invention, the information pulse It is composed of 8 wide pulses and narrow pulses with the same time intervals, carrying 8 bits of binary information. The data combination state of the 8 bits of information represents the meteorological type information and control information to be transmitted, as shown in Table 1.

[0039] Table 1 Correspondence table between data combination status and instruction information

[0040]

[0041] Typically, the correspondence between the 8-bit data combination state and the instruction information is not limited to Table 1. Only examples are given here. As long as the correspondence between the 8-bit data combination state and the instruction information satisfies a one-to-one correspondence, other example forms will not be repeated here.

[0042] Furthermore, in the technical solution disclosed in the embodiment of the present invention, pulse width modulation is used to load information onto the carrier wave, and the sonde only needs an adder to demodulate the information when decoding, which occupies little resources. Typically, after the sonde receives the command waveform of the ground radar, it samples after down-conversion, first takes the absolute value of the sampled value, then filters and averages it, and the value greater than half of the maximum value is recorded as the rising edge, and the value less than half of the maximum value is recorded as the falling edge, and the pulse width between the rising edge and the falling edge is recorded and measured. Thus, the transmitted command information can be obtained according to the pulse width. Typically, a pulse width of 2±0.2μs is recorded as 1, and a pulse width of 1±0.1μs is recorded as 0. In the decoding process, only comparators and adders are used, and multipliers are not required. Information can be demodulated according to the pulse width after filtering. Therefore, the hardware implementation is simple, occupies little resources, and reduces costs.

[0043] Furthermore, in the technical solution disclosed in the embodiment of the present invention, the instruction waveform is also provided with a check bit pulse , set between the last information pulse and the termination pulse, the check bit pulse With the start pulse The time interval is , the time width is ,in, The total number of 0s in the meteorological type information and control information to be transmitted in the command waveform. A check pulse is reserved, and the check pulse duty cycle is 0.5. The demodulated code element can be checked by checking the pulse width to further improve the reliability of command information transmission.

[0044] In the prior art, the detection waveform emitted by the ground radar of the secondary wind sounding radar system is a narrow-band signal modulated by ASK. The detection waveform carries little energy and has weak anti-interference ability, resulting in a low signal-to-noise ratio for the airborne sounding instrument. This makes it difficult for the airborne sounding instrument to respond to the "inquiry signal" of the ground radar in a timely manner, easily leading to the phenomenon of "questions without answers".

[0045] In order to solve the problems existing in the prior art, in the technical solution disclosed in the embodiment of the present invention, the ground radar uses a linear frequency modulation signal to form a detection waveform. The linear frequency modulation signal has a large time-bandwidth product and a strong anti-interference ability. The airborne sonde can process the gain by pulse compression, which can significantly improve the received signal-to-noise ratio. Therefore, after receiving the interrogation waveform of the ground radar, the airborne sonde can ensure that the airborne sonde responds to the "interrogation signal" of the ground radar in a timely manner and transmits the meteorological detection signal to the ground in real time.

[0046] In the prior art, since the sonde is triggered by the "inquiry signal" of the ground radar and then transmits the "response signal", there is a delay, and the inconsistency of the sonde delay is an important factor affecting the ranging accuracy of the secondary wind radar. Since the detection waveform emitted by the ground radar in the prior art is a narrow-band signal using ASK modulation, and the signal is easily affected by channel noise, it is difficult for the airborne sonde to accurately capture the rising edge of the ground radar "inquiry signal" and cannot trigger the "response signal" in time, resulting in inaccurate measurement of the transmission delay between the "inquiry signal" and the "response signal", which reduces the ranging accuracy.

[0047] In order to solve the problems existing in the prior art, in the technical solution disclosed in the embodiment of the present invention, the ground radar uses a linear frequency modulation signal to form a detection waveform, triggering the aerial sonde to transmit a "response signal". Since the linear frequency modulation signal has a large time-bandwidth product and a strong anti-interference ability, and the pulse accumulation characteristics of the multiple linear frequency modulation signals contained in the detection waveform enable the sonde to greatly improve the signal-to-noise ratio of the received ground radar detection signal, accurately capture the rising edge of the ground radar "interrogation signal", and trigger the "response signal" in time, which greatly improves the timing accuracy, thereby improving the ranging accuracy and angle measurement accuracy of the system. Typically, the timing of transmitting the sonde response waveform is: after the sonde receives the ground radar interrogation waveform, it delays 2060μs and then transmits the sonde response waveform.

[0048] In the prior art, the ground radar of the secondary wind sounding radar system sends a detection waveform, i.e., an "inquiry signal", which triggers the aerial sonde to send back a response waveform containing a sounding code, i.e., an "answer signal", to achieve the transmission of meteorological detection data. However, the ground detection waveform and the sonde response waveform of the existing system are not related to each other and are two completely different waveforms, which increases the complexity of the ground radar in processing the sonde signal. In addition, the anti-interference ability of the response waveform in the existing system results in a low reception signal-to-noise ratio of the response waveform received by the ground radar, and even the phenomenon of being unable to extract meteorological information may occur.

[0049] In order to solve the problems existing in the prior art, in the technical solution disclosed in the embodiment of the present invention, the sonde adopts a storage-modulation-forwarding method to form a response waveform, which not only eliminates the traditional resonance module, phase shift module, etc., reduces costs, reduces power consumption and volume, and improves the endurance time of the sonde; at the same time, it also makes the sonde response waveform and the ground radar detection waveform have good autocorrelation characteristics, and the channel noise interference can be effectively resisted by using this autocorrelation; further, the linear frequency modulation waveform contained in the response waveform enhances the signal-to-noise ratio of the response signal received and processed by the ground radar, and the pulse compression and pulse accumulation processing can greatly improve the signal-to-noise ratio of the weak response signal of the sonde received by the ground radar; further, the response waveform is formed by secondary modulation of the phase or amplitude of the linear frequency modulation pulse, that is, the linear frequency modulation signal can be used to transmit information; the ground radar can use pulse compression to obtain code element information to demodulate the pulse signal, and use the demodulated signal for coherent accumulation to further improve the signal-to-noise ratio. Pulse accumulation can also improve the signal-to-noise ratio of the signal, which is beneficial to improving the reliability of meteorological detection information transmission, and is also beneficial to improving the ranging accuracy and angle measurement accuracy of the ground radar.

[0050] In the prior art, the code rate or waveform time length of the detection waveform emitted by the ground radar and the response waveform emitted by the sonde always remains unchanged, regardless of the distance between the ground radar and the sonde and the working mode. This can easily lead to insufficient signal processing gain during long-distance detection and waste of signal processing gain during close-range detection.

[0051] In order to solve the problems existing in the prior art, in the technical solution disclosed in the embodiment of the present invention, the code rate or waveform time length of the radar detection waveform and the sonde response waveform is closely related to the distance between the ground radar and the sonde, and is closely related to the working mode. Different code rates or waveform time lengths are set in the long-distance detection and short-distance detection cases, which improves the signal processing gain during long-distance detection, avoids the waste of signal processing gain during short-distance detection, rationally utilizes energy consumption, and is conducive to increasing the airborne working time of the aerial sonde.

[0052] Typically, in the technical solution disclosed in the embodiment of the present invention, the radar detection waveform has different waveforms in different working modes:

[0053] In the general working mode, the radar detection waveform has a frame length of 1920 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 60 μs;

[0054] In the long-distance working mode, the radar detection waveform has a frame length of 3840μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 120μs or 64 linear frequency modulation waveforms with a repetition period of 60μs; in the long-distance working mode, the spatial attenuation is strong, the signal-to-noise ratio of the sonde is low, and a higher processing gain is required. Increasing the code rate of the radar detection waveform or increasing the length of the radar transmission waveform is conducive to improving the signal-to-noise ratio of the sonde and improving the signal processing gain.

[0055] In the close-range working mode, the radar detection waveform has a frame length of 960μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 30μs or 16 linear frequency modulation waveforms with a repetition period of 60μs. In the close-range working mode, the spatial attenuation is low, the signal-to-noise ratio of the sonde reception is high, and a high processing gain is not required. Reducing the code rate of the radar detection waveform or reducing the length of the radar transmission waveform is conducive to reducing the working time of the sonde receiving channel, reducing the power consumption of the sonde system, and extending the working time.

[0056] Furthermore, in the technical solution disclosed in the embodiment of the present invention, the sonde adopts a store-modulate-forward method to form a response waveform. When the detection waveform emitted by the ground radar adjusts the waveform code rate or time length according to the transmission distance or working mode, the response waveform emitted by the sonde will also be adjusted accordingly to make its code rate or waveform time consistent with the ground radar. In this way, the processing gain of the ground radar for the response waveform is also adjusted accordingly, which is beneficial to improving the ground radar's processing capability for the response signal.

[0057] Although the embodiments of the present invention have been disclosed above, they are not limited to the application methods listed in the specification and the embodiment. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Therefore, without departing from the general concept defined by the claims and equivalent scope, the present invention is not limited to specific details.

Claims

1. A method for generating an integrated waveform of a secondary wind sounding radar, characterized in that: Includes ground radar interrogation waveform and radiosonde response waveform; in, The ground radar interrogation waveform consists of a command waveform and a detection waveform. The command waveform is used to transmit meteorological type information and control information, and the detection waveform is used to detect the motion state of the balloon in the air. The command waveform is formed by carrier modulation of a start pulse, a stop pulse and a plurality of information pulses, and the detection waveform includes a plurality of linear frequency modulation waveforms repeated in a time period. The ground radar interrogation waveform is expressed as: ； in, Indicates the start pulse, Indicates the termination pulse, Represents information pulse, represents the time interval between the information pulse and the start pulse, represents the time interval between the end pulse and the start pulse, represents the time interval between the first linear frequency modulation waveform and the start pulse, Indicates the number of linear frequency modulation waveforms, represents the time repetition period of the linear frequency modulation waveform, Indicates the frequency modulation slope; and Indicates the carrier frequency; The sonde forms a response waveform by a store-modulate-forward method. Specifically, the sonde receives the detection waveform emitted by the ground radar and stores it according to the time repetition period. The sonde prepares the meteorological type data to be transmitted according to the received command waveform, reads the detection waveform according to the time repetition period, and uses amplitude modulation or phase modulation to load the meteorological type data to be transmitted onto the detection waveform to form a response waveform, which is then sent to the ground radar.

2. The integrated waveform generation method for secondary wind sounding radar according to claim 1, characterized in that: The information pulse It is composed of multiple wide pulses and narrow pulses with the same time intervals. The wide pulses and narrow pulses represent digital information 1 and 0 respectively. Pulse width modulation is used to load the information onto the carrier to form a command waveform modulation signal.

3. The integrated waveform generation method for secondary wind sounding radar according to claim 1 is characterized in that: The radar detection waveform has different waveforms in different working modes: In the general working mode, the radar detection waveform has a frame length of 1920 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 60 μs; In the long-range working mode, the radar detection waveform has a frame length of 3840 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 120 μs or 64 linear frequency modulation waveforms with a repetition period of 60 μs; In the short-range working mode, the radar detection waveform has a frame length of 960 μs, which is composed of 32 linear frequency modulation waveforms with a repetition period of 30 μs or 16 linear frequency modulation waveforms with a repetition period of 60 μs.

4. The integrated waveform generation method for secondary wind sounding radar according to claim 1 is characterized in that: The instruction waveform is also provided with a check bit pulse , set between the last information pulse and the termination pulse, the check bit pulse With the start pulse The time interval is , the time width is ,in, is the total number of 0s in the meteorological type information and control information to be transmitted in the command waveform.

5. The integrated waveform generation method for secondary wind sounding radar according to claim 1 is characterized in that: The timing of transmitting the sonde response waveform is: after the sonde receives the ground radar interrogation waveform, it delays for 2060 μs and then transmits the sonde response waveform.

6. The integrated waveform generation method for secondary wind sounding radar according to claim 1 is characterized in that: The time repetition period of the linear frequency modulation waveform Includes the waveform sending period and the waveform stopping period.

7. The integrated waveform generation method for secondary wind sounding radar according to claim 1 is characterized in that: The carrier frequency and Works in the microwave L band.

8. The integrated waveform generation method for secondary wind sounding radar according to claim 2 is characterized in that: The information pulse It is composed of 8 wide pulses and narrow pulses with the same time intervals, carrying 8 bits of binary information, and the data combination state of the 8 bits of information represents the meteorological type information and control information to be transmitted.

9. The integrated waveform generation method for secondary wind sounding radar according to claim 2, characterized in that: The information pulse The pulse width of the wide pulse is 2μs, and the pulse width of the narrow pulse is 1μs.

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