CN106130944B - Pulse modulation signal reception processing system and method - Google Patents

Abstract

The invention discloses a pulse modulation signal receiving and processing system and method. The system includes an automatic gain control amplifier, a squarer, a low-pass filter, a fixed pulse width decision device, a trigger analog-to-digital converter and a differential phase demodulator ; The input end of the automatic gain control amplifier inputs a pulse-type 2DPSK modulation signal, the output end of the automatic gain control amplifier is connected to the input end of the squarer and the signal input end of the trigger-type analog-to-digital converter, and the output end of the squarer is connected to the low-pass filter The input end, the output end of the low-pass filter is connected to the input end of the fixed pulse width decision device, the output end of the fixed pulse width decision device is connected to the synchronous trigger input end of the trigger type analog-to-digital converter, and the output end of the trigger type analog-to-digital converter Connect to the input of the differential phase demodulator. The invention directly performs carrier recovery and outputs baseband absolute code data, has the characteristics of low power consumption, low complexity, high speed and easy integration, and meets the requirements of human body medium transmission applications.

Description

Pulse modulation signal receiving and processing system and method

technical field

The present invention relates to the technical field of human body medium communication, in particular to a pulse modulation signal receiving and processing system and method.

Background technique

With the rapid development of electronic information technology, wireless communication technology, semiconductor integrated circuit technology, and biomedical technology, and the continuous improvement of people's demand for wireless applications, the body area network (BAN, BodyAreaNetwork) communication system with the human body as the medium is because of its portability. , low power consumption, and low complexity, it can well meet the needs of real-time measurement and monitoring of human body signs in medical, aerospace, sports, and military fields, and has gradually become one of the hot spots in the research of next-generation mobile communication technology. one.

Compared with traditional wireless communication methods, the advantages of human body medium communication are that it can be nearly fully automated, can be continuously or periodically detected, has strong flexibility, high reliability and high precision (body area network sensors attached to the human body can effectively and High-precision processing of human physical signals), high efficiency (long service life of nodes under low power consumption), low cost, low power consumption, high confidentiality, and low human damage, etc., and there is no reduction in efficiency when multiple people communicate question. Therefore, research on communication systems using the human body itself as a transmission medium has become an urgent need in the industry.

At present, the industry is still in the initial research stage of signal modulation and demodulation technology in the field of human body media communication. Most of them are carried out around human body channels, data access, networking and signal processing algorithms. Only a few teams use discrete components. A hardware experiment system for human body medium transmission has been preliminarily built. There are few reports on the modulation and demodulation technology of human body medium communication. ), 2FSK (binary frequency shift keying) and other modulation and demodulation technologies. In contrast, 2PSK (binary phase shift keying) has better bit error rate performance, but there is phase uncertainty in the 2PSK signal transmission system, which will cause the inversion of received symbols "0" and "1", A bit error occurs. In order to maintain the advantages of 2PSK and reduce the bit error rate, the 2PSK modulation is improved to binary differential phase shift keying modulation. 2DPSK (Binary Differential Keying Phase Shift Keying) modulation technology has the advantages of high transmission efficiency, strong anti-interference ability, and excellent bit error rate performance. However, since the 2DPSK modulation signal does not contain a carrier component, carrier recovery cannot be performed directly, so the existing demodulation methods are all through the square loop phase-locked loop correlation demodulation method and the Costas ring correlation demodulation method using complex circuits Recovering a coherent carrier that is strictly synchronized with the modulated carrier virtually increases the complexity and energy consumption of the receiving system, and leads to a larger chip area and power consumption after system integration, and needs to withstand a higher operating frequency.

Contents of the invention

Based on the above situation, the present invention proposes a pulse modulation signal receiving and processing system and method, which directly performs carrier recovery to output baseband absolute code data, has the characteristics of low power consumption, low complexity, high speed, and easy integration, and meets the application of human body medium transmission demand.

In order to achieve the above object, the embodiment of the technical solution of the present invention is:

A pulse modulation signal receiving and processing system, including an automatic gain control amplifier, a squarer, a low-pass filter, a fixed pulse width decision device, a trigger type analog-to-digital converter and a differential phase demodulator;

The input terminal of the automatic gain control amplifier inputs a pulsed 2DPSK modulation signal, and the output terminal of the automatic gain control amplifier is respectively connected to the input terminal of the squarer and the signal input terminal of the trigger analog-to-digital converter. The output end of the squarer is connected to the input end of the low-pass filter, the output end of the low-pass filter is connected to the input end of the fixed pulse width decision device, and the output end of the fixed pulse width decision device is connected to the The synchronous trigger input terminal of the trigger-type analog-to-digital converter, the output terminal of the trigger-type analog-to-digital converter is connected to the input terminal of the differential phase demodulator.

A method for receiving and processing a pulse modulation signal, comprising the following steps:

performing automatic gain control amplification on the pulsed 2DPSK modulation signal to obtain an amplitude envelope stabilization signal, and outputting the amplitude envelope stabilization signal in two paths;

Perform square operation on the first amplitude envelope stabilization signal;

Extracting the envelope signal in the first path of amplitude envelope stabilization signal after the squaring operation;

Judging the envelope signal, performing pulse stretching on the determined envelope signal according to the preset pulse width to obtain a synchronous digital pulse signal, the preset pulse width is set according to the pulse width of the amplitude envelope stabilization signal ;

Sampling the second amplitude envelope stabilization signal with a preset sampling rate according to the synchronous digital pulse signal, and the preset sampling rate is set according to the carrier frequency of the amplitude envelope stabilization signal;

Baseband absolute code data is obtained according to two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after.

Compared with the prior art, the beneficial effects of the present invention are: the pulse modulation signal receiving and processing system and method of the present invention, the automatic gain control amplifier performs automatic gain control amplification on the pulsed 2DPSK modulation signal, and obtains a stable amplitude envelope signal; the squarer Perform square operation on the first amplitude envelope stabilization signal; low-pass filter extracts the envelope signal in the signal after square operation; the fixed pulse width decision device judges the extracted envelope signal, and performs The determined envelope signal is pulse-stretched to obtain a synchronous digital pulse signal; when the synchronous digital pulse signal is input to the trigger-type analog-to-digital converter, the trigger-type analog-to-digital converter adopts a preset sampling rate for the second amplitude envelope stabilization signal Sampling; finally, the differential phase demodulator restores and outputs the baseband absolute code data in one step according to the two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal twice before and after. The invention adopts the pulse type 2DPSK modulation signal to improve the frequency band utilization rate of the human body channel and the transmission rate. In exchange for the advantages, the energy consumption per bit of the system is significantly reduced, and it can be completely realized by CMOS (Complementary Metal Oxide Semiconductor, Complementary Metal Oxide Semiconductor) integrated circuit technology. There is no large-area integrated resistor and capacitor shaping circuit, which is suitable for integration in SOC (Systemon Chip, system-on-chip) chip has good promotion value.

Description of drawings

Fig. 1 is a schematic structural diagram of a pulse modulation signal receiving and processing system in an embodiment;

Fig. 2 is a structural schematic diagram of a differential phase demodulator in an embodiment;

Fig. 3 is a schematic structural diagram of a phase comparator in an embodiment;

Fig. 4 is a schematic structural diagram of a pulse modulation signal receiving and processing system based on a specific example of the system shown in Fig. 1;

Fig. 5 is an application example of a pulse modulation signal receiving and processing system;

Fig. 6 is a flowchart of a method for receiving and processing a pulse modulation signal in an embodiment.

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, and do not limit the protection scope of the present invention.

In one embodiment, the pulse modulation signal receiving and processing system, as shown in Figure 1, includes an automatic gain control amplifier 101, a squarer 102, a low-pass filter 103, a fixed pulse width decision device 104, a trigger-type analog-to-digital converter 105 and a differential Phase demodulator 106;

The input terminal of the automatic gain control amplifier 101 inputs a pulsed 2DPSK modulation signal, and the output terminal of the automatic gain control amplifier 101 is respectively connected to the input terminal of the squarer 102 and the signal input of the trigger type analog-to-digital converter 105 end, the output end of the squarer 102 is connected to the input end of the low-pass filter 103, and the output end of the low-pass filter 103 is connected to the input end of the fixed pulse width determiner 104, and the fixed pulse width The output terminal of the decision unit 104 is connected to the synchronous trigger input terminal of the trigger analog-digital converter 105 , and the output terminal of the trigger analog-digital converter 105 is connected to the input terminal of the differential phase demodulator 106 .

The automatic gain control amplifier 101 performs automatic gain control amplification on the pulsed 2DPSK modulation signal, and outputs two channels of amplitude envelope stabilization signals; the squarer 102 performs square operation on the first channel of amplitude envelope stabilization signals and outputs the squared amplitude envelope stabilization signals The low-pass filter 103 extracts the envelope signal in the amplitude envelope stabilization signal after the square operation; the fixed pulse width decision device 104 judges the extracted envelope signal, and the envelope after the decision is made according to the preset pulse width The signal is pulse-stretched to obtain a synchronous digital pulse signal; when the synchronous digital pulse signal arrives, the trigger-type analog-to-digital converter 105 uses a preset sampling rate to sample the second-way amplitude envelope stabilization signal; finally, the differential phase demodulator 106 According to the two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after, the baseband absolute code data is restored and output in one step.

The trigger-type analog-to-digital converter samples only when the synchronous digital pulse signal arrives, and the analog-to-digital converter enters the standby state and does not output data during the rest of the time.

It can be known from the above description that the pulse modulation signal receiving and processing system of the present invention adopts pulse type 2DPSK modulation signal to improve the frequency band utilization rate of the human body channel and increase the transmission rate. The system works in an all-digital trigger state and directly performs carrier recovery. With the advantages of low power consumption, low complexity and high speed, the energy consumption per bit of the system can be significantly reduced, and it can be completely realized by CMOS integrated circuit technology. There is no large-area integrated resistor and capacitor shaping circuit, suitable for integration in SOC The chip has good promotion value.

In addition, in a specific example, as shown in FIG. 2, the differential phase demodulator 106 includes a first shift register 1061, a second shift register 1062, and a phase comparator 1063;

The output end of the trigger-type analog-to-digital converter 105 is connected to the first shift register 1061, and the first output end of the first shift register 1061 is connected to the input end of the second shift register 1062, the The second output terminal of the first shift register 1061 and the output terminal of the second shift register 1062 are respectively connected to the input terminal of the phase comparator 1063 .

The trigger type analog-to-digital converter 105 outputs the first sampling data to the first shift register 1061, and the first shift register 1061 performs a shift register operation on the first sampling data to obtain the first shift register data d _n (t ), the trigger-type analog-to-digital converter 105 outputs the second sampling data to the first shift register 1061, and the first shift register 1061 outputs the first shift register data d _n (t) to the second shift register 1062, The second shift register 1062 outputs the first shift register data d _n (t) to the phase comparator 1063, and the first shift register 1061 performs a shift register operation on the second sampling data to obtain the second shift register data d _n+1 (t), the first shift register 1061 outputs the second shift register data d _n+1 (t) to the phase comparator 1063, and the phase comparator 1063 is based on the first shift register data d _n (t) and The second shift register data d _n+1 (t) outputs baseband absolute code data.

In addition, in a specific example, as shown in FIG. 3 , the phase comparator 1063 includes a digital multiplication circuit 10631, an average value acquisition circuit 10632 and a threshold decision circuit 10633;

The second output end of the first shift register 1061 is connected to the first input end of the digital multiplication circuit 10631, and the output end of the second shift register 1062 is connected to the second input end of the digital multiplication circuit 10631, The output end of the digital multiplication circuit 10631 is connected to the input end of the average value acquisition circuit 10632 , and the output end of the average value acquisition circuit 10632 is connected to the input end of the threshold decision circuit 10633 .

For example, the first shift register 1061 outputs the signal d _n (t), and the second shift register 1062 outputs the signal d _n+1 (t), then the digital multiplication circuit 10631 multiplies the above two signals, and obtains through the mean value acquisition circuit 10632 The digital multiplication circuit 10631 outputs the DC mean value of the product, and the threshold judgment circuit 10633 outputs "logic 1" or "logic 0" corresponding to the DC mean value and a preset mathematical threshold, so as to realize demodulation of pulsed 2DPSK non-correlated signals .

In addition, in a specific example, the above-mentioned system further includes a low-noise amplifier, the input of the low-noise amplifier inputs the pulsed 2DPSK modulation signal, and the output of the low-noise amplifier is connected to the input of the automatic gain control amplifier end.

The noise figure of the low noise amplifier is very low. In the case of amplifying weak signals, the noise of the low noise amplifier itself has little interference with the signal, which improves the signal-to-noise ratio of the output.

In addition, in a specific example, the above-mentioned system further includes a frequency-selective filter, the input end of the frequency-selective filter inputs the pulsed 2DPSK modulation signal, and the output end of the frequency-selective filter is connected to the low-noise amplifier input terminal.

Here, according to the actual needs, the signal of a specific frequency band in the pulsed 2DPSK modulation signal can be obtained through the frequency selective filter for subsequent research and processing, which is suitable for application.

In addition, in a specific example, the fixed pulse width determiner includes a determiner and a fixed pulse stretcher;

The output end of the low-pass filter is connected to the input end of the decision device, the output end of the decision device is connected to the input end of the fixed pulse stretcher, and the output end of the fixed pulse stretcher is connected to the trigger Synchronization Trigger Input for the Analog-to-Digital Converter.

The decider judges the signal output by the low-pass filter, and the fixed pulse stretcher can set the pulse stretching width according to actual needs, and performs pulse stretching on the signal output by the decider to ensure that the follow-up processing is carried out normally.

In order to better understand the above system, an application example of the pulse modulation signal receiving and processing system of the present invention will be described in detail below.

As shown in Figure 4, the system may include a frequency selective filter 401, a low noise amplifier 402, an automatic gain control amplifier 403, a squarer 404, a low pass filter 405, a decision device 406, a fixed pulse stretcher 407, a trigger Analog-to-digital converter 408 and differential phase demodulator 409;

The input terminal of the frequency selective filter 401 inputs the pulse type 2DPSK modulation signal, the output terminal of the frequency selective filter 401 is connected to the input terminal of the low noise amplifier 402, and the output terminal of the low noise amplifier 402 is connected to the input terminal of the automatic gain control amplifier 403, automatically The output end of the gain control amplifier 403 is connected to the input end of the squarer 404 and the signal input end of the trigger type analog-to-digital converter 408 respectively, and the output end of the squarer 404 is connected to the input end of the low-pass filter 405, and the input end of the low-pass filter 405 The output end is connected to the input end of the decision device 406, the output end of the decision device 406 is connected to the input end of the fixed pulse stretcher 407, and the output end of the fixed pulse stretcher 407 is connected to the synchronous trigger input end of the trigger type analog-to-digital converter 408, triggering The output end of mode analog-to-digital converter 408 is connected to the input end of differential phase demodulator 409;

The differential phase demodulator 409 includes a first shift register 4091, a second shift register 4092, a digital multiplication circuit 4093, an average value acquisition circuit 4094 and a threshold decision circuit 4095;

The output end of the trigger type analog-to-digital converter 408 is connected to the first shift register 4091, the first output end of the first shift register 4091 is connected to the input end of the second shift register 4092, and the second output of the first shift register 4091 terminal is connected to the first input end of the digital multiplication circuit 4093, the output end of the second shift register 4092 is connected to the second input end of the digital multiplication circuit 4093, and the output end of the digital multiplication circuit 4093 is connected to the input end of the mean value acquisition circuit 4094, and the mean value acquisition The output end of the circuit 4094 is connected to the input end of the threshold decision circuit 4095 .

Specifically, the frequency-selective filter 401 performs frequency-selective filtering on the broadband pulse-type 2DPSK modulation signal passing through the human body medium, the low-noise amplifier 402 amplifies the wide-band pulse-type 2DPSK modulation signal after frequency-selective filtering, and the automatic gain control amplifier 403 The wideband pulse type 2DPSK modulated signal of a certain frequency band after amplifying carries out automatic gain control amplification, obtains amplitude envelope stable signal r(t), divides two-way output amplitude envelope stable signal r(t), and the squarer 404 pairs the first Square amplitude envelope stabilization signal r(t) to obtain signal a(t), further noise suppression and filtering by low-pass filter 405 to obtain signal b(t), and determine b(t) through decision unit 406 Finally, the fixed-width pulse stretching operation is performed by the fixed pulse stretcher 407 to obtain the synchronous digital pulse c(t). The pulse width of c(t) must be greater than the pulse width of the signal r(t), so as to ensure the trigger mode The digital converter 408 can collect effective pulse information in r(t) every time sampling, and the data length (the number of sampling points) of each group of data d _n (t) outputted by each sampling time length and sampling is the same , when the synchronous digital pulse c(t) arrives, the second amplitude envelope stabilization signal r(t) is sampled by the trigger-type analog-to-digital converter 408 at a sampling frequency greater than or equal to 2 times the carrier frequency of r(t) , obtain the data dn(t) (n corresponds to the number of samples), and recover and output baseband absolute code data e(t) and synchronous digital pulse c(t) in one step through the differential phase demodulator 409;

Here the synchronous digital pulse c(t) is the supporting synchronous clock as the final demodulation output absolute code data e(t) of the system;

Further, the trigger-type analog-to-digital converter 408 samples only when the synchronous pulse of the signal c(t) arrives, and the collected data is the digital form of the corresponding pulse signal in r(t), while the trigger-type mode for the rest of the time The digital converter 408 enters the standby state and does not output data;

Further, the trigger-type analog-to-digital converter 408 outputs the first sampling data to the first shift register 4091, and the first shift register 4091 performs a shift register operation on the first sampling data to obtain the first shift register data d _n (t), the trigger type analog-to-digital converter 408 outputs the second sampling data to the first shift register 4091, and the first shift register 4091 outputs the first shift register data d _n (t) to the second shift register 4092, the second shift register 4092 outputs the first shift register data d _n (t) to the digital multiplication circuit 4093, and the first shift register 4091 performs a shift register operation on the second sampling data to obtain the second shift register data d _n+1 (t), the first shift register 4091 outputs the second shift register data d _n+1 (t) to the digital multiplication circuit 4093, for example, the output signal of the first shift register 4091 is expressed as d _n ( t)=COS(ωt), the output signal of the second shift register 4092 is expressed as d _n+1 (t)=COS(ωt+θ), and the output signal of the digital multiplication circuit 4093 can be expressed as: Obtain the DC average value signal through the average value acquisition circuit 4094 The size of the DC mean value signal q(t) reflects the phase difference information of d _n (t) and d _n+1 (t) data, and the threshold judgment circuit 4095 compares q(t) with a certain preset mathematical Threshold, corresponding to the output of "logic 1" or "logic 0", so as to realize the demodulation of pulsed 2DPSK non-correlated signals.

As shown in Figure 5, when the pulse modulation signal receiving and processing system is applied to human body media communication, the signal u _i generated by the signal source 51 is sent to the input terminal of the 2DPSK transmitter 52, and the output terminal of the 2DPSK transmitter 52 is worn on one of the people. The human body dielectric sensor 1 emits a broadband pulse 2DPSK signal u _n , and the signal un _is transmitted to the human body dielectric sensor 2 worn by another person through the human body dielectric channel constructed by two people shaking hands, and the human body dielectric sensor 2 outputs a broadband pulse Formula 2DPSK signal u' _n , then carry out pulse type 2DPSK non-correlation reception and demodulation to signal u' _n by the implementation example 53 of Fig. 4, output baseband data Data, finish to Data data processing by computer 54 internal upper computer at last, not It requires complex circuits such as carrier synchronization recovery, Costas ring, high-speed real-time acquisition, low complexity, low power consumption and easy integration.

As can be seen from the above description, the frequency selective filter in this embodiment performs frequency selective filtering on the wideband pulsed 2DPSK modulation signal passing through the human body medium, the low noise amplifier amplifies the wideband pulsed 2DPSK modulated signal after the frequency selective filtering, and the automatic gain control The amplifier performs automatic gain control amplification on the amplified broadband pulse 2DPSK modulation signal in a certain frequency band to obtain a stable amplitude envelope signal; the squarer performs square operation on the first amplitude envelope stable signal; the low-pass filter extracts the square signal The envelope signal in the signal after operation; the decision device judges the extracted envelope signal, and the fixed pulse stretcher performs pulse stretching on the determined envelope signal according to the preset pulse width to obtain a synchronous digital pulse signal; when the synchronous digital When the pulse signal arrives, the trigger-type analog-to-digital converter uses the preset sampling rate to sample the second amplitude envelope stable signal; finally, the differential phase demodulator obtains The adjacent two sampling data, one-step recovery output baseband absolute code data. The invention adopts the pulse type 2DPSK modulation signal to improve the frequency band utilization rate of the human body channel and the transmission rate. In exchange for the advantages, the energy consumption per bit of the system is significantly reduced, and it can be realized completely using CMOS integrated circuit technology. There is no large-area integrated resistor and capacitor shaping circuit. It is suitable for integration in SOC chips and has good promotion value.

In one embodiment, the pulse modulation signal receiving and processing method, as shown in Figure 6, includes the following steps:

Step S601: Perform automatic gain control amplification on the pulsed 2DPSK modulation signal to obtain a stable amplitude envelope signal, and output the stable amplitude envelope signal in two ways;

Step S602: performing a square operation on the first amplitude envelope stabilization signal;

Step S603: Extracting the envelope signal from the first amplitude envelope stabilization signal after the squaring operation;

Step S604: Judging the envelope signal, performing pulse stretching on the determined envelope signal according to the preset pulse width to obtain a synchronous digital pulse signal, the preset pulse width is based on the amplitude envelope stabilization signal Pulse width setting;

Step S605: Sampling the second amplitude envelope stabilization signal with a preset sampling rate according to the synchronous digital pulse signal, and the preset sampling rate is set according to the carrier frequency of the amplitude envelope stabilization signal;

Step S606: Obtain baseband absolute code data according to two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after.

Automatic gain control amplification is performed on the wideband pulsed 2DPSK modulation signal passing through the human body medium to obtain a stable amplitude envelope signal r(t), and the signal r(t) is divided into two outputs, namely a and b, and the a signal is processed After squaring, the signal a(t) is obtained, the envelope signal b(t) of the signal a(t) is extracted, the envelope signal b(t) is judged, and the determined envelope signal is pulsed according to the preset pulse width Stretching to obtain the synchronous digital pulse c(t), when the synchronous digital pulse c(t) arrives, the signal of channel b is sampled at the preset sampling frequency to obtain the data d _n (t) (n corresponds to the number of sampling times), according to the Two adjacent sampling data obtained by two samplings are restored and output baseband absolute code data e(t) and synchronous clock c(t) in one step.

As can be seen from the above description, the pulse modulation signal receiving and processing method of the present invention adopts the pulse type 2DPSK modulation signal to improve the frequency band utilization rate of the human body channel and increase the transmission rate. The system works in an all-digital trigger state and directly performs carrier recovery. With the advantages of low power consumption, low complexity and high speed, the energy consumption per bit of the system can be significantly reduced, and it can be completely realized by CMOS integrated circuit technology. There is no large-area integrated resistor and capacitor shaping circuit, suitable for integration in SOC The chip has good promotion value.

In addition, in a specific example, according to the two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after, the manner of obtaining the baseband absolute code data includes:

respectively performing a shift register operation on two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after, to obtain the first shift register data and the second shift register data;

multiplying the first shift-register data and the second shift-register data;

obtaining a DC mean value according to a multiplication result of the first shift-register data and the second shift-register data;

When the DC mean value is greater than the preset first threshold, output the first baseband absolute code data; when the DC mean value is less than the preset second threshold, output the second baseband absolute code data, the preset first threshold is greater than the preset second threshold.

For example, the first shift register data is expressed as d _n (t)=COS(ωt), the second shift register data is expressed as d _n+1 (t)=COS(ωt+θ), and the first shift The multiplication of the registered data and the second shifted registered data can be expressed as: get the DC mean The magnitude of the DC mean value signal q(t) reflects the phase difference information of d _n (t) and d _n+1 (t) data, compare q(t) with a certain preset mathematical threshold, and output correspondingly "Logic 1" or "Logic 0", so as to realize pulse-type 2DPSK non-correlated signal demodulation. When the DC average value is greater than the preset first threshold, it means that the phase difference between d _n (t) and d _n+1 (t) data is zero, and the first baseband absolute code data is output, that is, "logic 0". When the DC average value is less than When the second threshold is preset, it means that the phase difference between d _n (t) and d _n+1 (t) data is not zero, and the second baseband absolute code data is output, that is, “logic 1”.

In addition, in a specific example, before performing automatic gain control amplification on the pulsed 2DPSK modulation signal, the steps are further included:

Perform frequency-selective filtering and low-noise amplification on the pulsed 2DPSK modulation signal in sequence.

In the case of amplifying weak signals, low noise amplification can improve the signal-to-noise ratio of the output. According to actual needs, the signal of a specific frequency band in the pulsed 2DPSK modulation signal can be obtained through frequency-selective filtering for subsequent research and processing, which is suitable for application.

In addition, in a specific example, the preset pulse width is greater than the pulse width of the amplitude envelope stabilization signal, and the preset sampling rate is greater than or equal to twice the carrier frequency of the amplitude envelope stabilization signal.

The preset pulse width is greater than the pulse width of the amplitude envelope stable signal to ensure that effective pulse information in the amplitude envelope stable signal can be collected for each sampling, and the length of each sampling time and each set of data output by sampling d _n The data length (the number of sampling points) of (t) is the same.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A pulse-modulated signal receiving and processing system, characterized in that, comprises an automatic gain control amplifier, a squarer, a low-pass filter, a fixed pulse width decision device, a trigger-type analog-to-digital converter and a differential phase demodulator; The input terminal of the automatic gain control amplifier inputs a pulsed 2DPSK modulation signal, and the output terminal of the automatic gain control amplifier is respectively connected to the input terminal of the squarer and the signal input terminal of the trigger analog-to-digital converter. The output end of the squarer is connected to the input end of the low-pass filter, the output end of the low-pass filter is connected to the input end of the fixed pulse width decision device, and the output end of the fixed pulse width decision device is connected to the The synchronous trigger input terminal of the trigger-type analog-to-digital converter, the output terminal of the trigger-type analog-to-digital converter is connected to the input terminal of the differential phase demodulator; The automatic gain control amplifier performs automatic gain amplification on the pulsed 2DPSK modulation signal, and outputs two stable amplitude envelope signals; the squarer performs square operation on the first amplitude envelope signal and outputs the squared amplitude envelope stable signal ; The low-pass filter extracts the envelope signal in the amplitude envelope stabilization signal after the square operation; the fixed pulse width decision device judges the extracted envelope signal, and judges the extracted envelope signal according to the preset pulse width. The envelope signal is pulse-stretched to obtain a synchronous digital pulse signal; the trigger-type analog-to-digital converter uses a preset sampling rate to sample the second-way amplitude envelope stabilization signal; the differential phase demodulator is based on the second-way Two adjacent sampling data are obtained by sampling the amplitude envelope stabilization signal two times before and after, and output the baseband absolute code data. 2. The pulse modulation signal receiving and processing system according to claim 1, wherein the differential phase demodulator comprises a first shift register, a second shift register and a phase comparator; The output end of the trigger-type analog-to-digital converter is connected to the first shift register, the first output end of the first shift register is connected to the input end of the second shift register, and the first shift register The second output end of the register and the output end of the second shift register are respectively connected to the input end of the phase comparator. 3. The pulse modulation signal receiving and processing system according to claim 2, wherein the phase comparator comprises a digital multiplication circuit, an average value acquisition circuit and a threshold decision circuit; The second output end of the first shift register is connected to the first input end of the digital multiplication circuit, the output end of the second shift register is connected to the second input end of the digital multiplication circuit, and the digital multiplication The output end of the circuit is connected to the input end of the average value acquisition circuit, and the output end of the average value acquisition circuit is connected to the input end of the threshold judgment circuit. 4. according to the described pulse modulation signal reception processing system according to any one of claims 1 to 3, it is characterized in that, also comprise low-noise amplifier, the input terminal of described low-noise amplifier inputs described pulse type 2DPSK modulation signal, so The output end of the low noise amplifier is connected to the input end of the automatic gain control amplifier. 5. The pulse-modulated signal receiving and processing system according to claim 4, further comprising a frequency-selective filter, the input of the frequency-selective filter inputs the pulsed 2DPSK modulation signal, and the frequency-selective filter The output terminal of the device is connected to the input terminal of the low noise amplifier. 6. The pulse modulation signal receiving and processing system according to claim 1, wherein the fixed pulse width decision device comprises a decision device and a fixed pulse stretcher; The output end of the low-pass filter is connected to the input end of the decision device, the output end of the decision device is connected to the input end of the fixed pulse stretcher, and the output end of the fixed pulse stretcher is connected to the modulus Synchronization Trigger Input for Converter. 7. A method for receiving and processing a pulse modulation signal, comprising the following steps: performing automatic gain control amplification on the pulsed 2DPSK modulation signal to obtain an amplitude envelope stabilization signal, and outputting the amplitude envelope stabilization signal in two paths; Perform square operation on the first amplitude envelope stabilization signal; Extracting the envelope signal in the first path of amplitude envelope stabilization signal after the squaring operation; Judging the envelope signal, performing pulse stretching on the determined envelope signal according to the preset pulse width to obtain a synchronous digital pulse signal, the preset pulse width is set according to the pulse width of the amplitude envelope stabilization signal ; Sampling the second amplitude envelope stabilization signal with a preset sampling rate according to the synchronous digital pulse signal, and the preset sampling rate is set according to the carrier frequency of the amplitude envelope stabilization signal; Baseband absolute code data is obtained according to two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after. 8. The pulse modulation signal receiving and processing method according to claim 7, characterized in that, according to the two adjacent sampling data obtained by sampling the second road amplitude envelope stabilization signal before and after two times, the baseband absolute code is obtained Data formats include: respectively performing a shift register operation on two adjacent sampling data obtained by sampling the second amplitude envelope stabilization signal two times before and after, to obtain the first shift register data and the second shift register data; multiplying the first shift-register data and the second shift-register data; obtaining a DC mean value according to a multiplication result of the first shift-register data and the second shift-register data; When the DC mean value is greater than the preset first threshold, output the first baseband absolute code data; when the DC mean value is less than the preset second threshold, output the second baseband absolute code data, the preset first threshold is greater than the preset second threshold. 9. The pulse modulation signal receiving and processing method according to claim 7 or 8, characterized in that, before the automatic gain control amplification is carried out to the pulse type 2DPSK modulation signal, the steps also include: Perform frequency-selective filtering and low-noise amplification on the pulsed 2DPSK modulation signal in sequence. 10. The pulse modulation signal receiving and processing method according to claim 7, wherein the preset pulse width is greater than the pulse width of the amplitude envelope stabilization signal, and the preset sampling rate is greater than or equal to twice The amplitude envelope stabilizes the carrier frequency of the signal.