Wireless transmission modulation and demodulation method, wireless information transmission device, transmitting end and receiving end
Through the multi-component periodic frequency modulation signal modulation and demodulation method, the problems of insufficient wireless transmission distance and reliability in complex environments are solved, and efficient information transmission is achieved in environments with severe multipath interference and Doppler frequency shift.
Patent Information
- Application Number
- CN202411898942.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2044-12-20
AI Technical Summary
Existing wireless signal modulation and demodulation methods are difficult to meet the transmission distance and reliability requirements in complex environments, especially in urban multipath environments and heavy rainfall or rapid carrier movement where fading is severe and Doppler frequency shift is large, which shortens the transmission distance and reduces the reliability.
A multi-component periodic frequency modulation signal modulation and demodulation method is adopted. The transmitter generates a multi-component periodic frequency modulation signal and modulates the binary information code onto it. The receiver demodulates it into a binary information code through periodic resampling frequency domain energy detection. The characteristics of frequency domain energy dispersion and strong energy concentration are utilized to improve the transmission distance and reliability.
The wireless transmission distance and reliability are significantly improved in complex environments, the processing gain is increased by about Z1×Z2 times, and the ability to resist multipath interference and Doppler frequency shift is strong, solving the problems of reduced transmission distance and reduced reliability in existing technologies.
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Figure CN119766607B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of wireless communication technology, and in particular to a wireless transmission modulation and demodulation method, a wireless information transmission device, a transmitter, and a receiver. Background Art
[0002] With the increasing demand for information technology, the transmission of critical information such as the safety status, distress messages, and emergency instructions of people, livestock, and equipment in complex environments has attracted widespread attention. However, due to space and economic cost constraints, the transmission distance and reliability of existing wireless signal modulation and demodulation methods and information transmission equipment are difficult to meet these requirements. For example, devices based on chirp spread spectrum modulation have strong Doppler and multipath resistance, enabling long-distance transmission at low transmit power in open, low-dynamic environments. However, their transmission distance is significantly reduced in urban multipath environments, and information transmission reliability is reduced in environments with severe fading and large Doppler shifts due to heavy rainfall or rapid carrier motion. Multi-antenna diversity technology can improve information transmission reliability in selective fading channels, but it requires relatively accurate channel information, is complex, and is not suitable for environments with rapidly changing channel conditions. Summary of the Invention
[0003] In response to the problems existing in the above-mentioned prior art, the purpose of this application is to provide a wireless transmission modulation and demodulation method, a wireless information transmission device, a transmitter and a receiver, which can improve the wireless transmission distance and reliability of information in complex environments.
[0004] To achieve the above objectives, this application provides the following solutions.
[0005] In a first aspect, the present application provides a wireless transmission modulation and demodulation method, comprising:
[0006] The transmitter obtains the binary information code of the information to be transmitted and sets the code element width and transmission bandwidth;
[0007] The transmitter generates a multi-component periodic frequency modulation signal according to the symbol width and transmission bandwidth;
[0008] The transmitter modulates the binary information code onto the multi-component periodic frequency modulation signal to generate a modulated signal;
[0009] The transmitter adjusts the modulated signal to the transmission frequency and transmits it at the specified power;
[0010] The receiving end performs frequency conversion and digital processing on the received signal to obtain a digital received signal;
[0011] The receiving end detects whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determines the starting position of the code element;
[0012] After the receiving end determines the starting position of the code element, it uses the periodic resampling frequency domain energy detection method to demodulate the information on the modulated signal into a binary information code;
[0013] The receiving end decodes the binary information code to obtain the transmitted information.
[0014] Optionally, the transmitting end obtains a binary information code of information to be transmitted and sets a code element width and a transmission bandwidth, specifically including:
[0015] The transmitter obtains the information to be transmitted;
[0016] Binary encode the information to be transmitted to obtain the corresponding binary information code;
[0017] The symbol width T and transmission bandwidth B are set according to the transmission environment and transmission rate requirements.
[0018] Optionally, the transmitting end generates a multi-component periodic frequency modulation signal according to the symbol width and the transmission bandwidth, specifically including:
[0019] The transmitting end generates Z1 periodic frequency modulated signals as a multi-component periodic frequency modulated signal; where Z1 is the number of components; the Z1 periodic frequency modulated signals meet the following conditions: the carrier frequencies are equal, the bandwidth is less than or equal to the transmission bandwidth B, the minimum common period P is one Nth of the code element width T, and N is a positive integer.
[0020] Optionally, the transmitting end modulates the binary information code onto a multi-component periodic frequency modulation signal to generate a modulated signal, specifically including:
[0021] The transmitter modulates the multi-component periodic frequency modulation signal according to the binary information code and the code element width T; when transmitting the binary code 1, it transmits Z1 periodic frequency modulation signals with a duration of T; when transmitting the binary code 0, it does not transmit a signal for a duration of T.
[0022] Optionally, the receiving end performs frequency conversion and digital processing on the received signal to obtain a digital received signal, specifically including:
[0023] The receiving end uses Z2 antennas to receive signals, and performs frequency conversion and digital processing on the received signals. The received signals of each channel are superimposed to obtain the digital received signal S r =[x1,x2,x3,…,x t ,…]; where the subscript t = 1, 2, 3,… represents the sampling point number; Z2 is a positive integer.
[0024] Optionally, the receiving end detects whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determines the starting position of the code element, specifically including:
[0025] The receiving end determines the observation window length L according to the set code element width T, and sets the observation window length L = T;
[0026] To S r Perform the starting end detection, take one sampling point as the starting position of the sliding observation window, and record the data sequence selected by the qth sliding observation window as S q =[x q ,x q+1 ,…,x q+L-1 ];
[0027] For the selected data sequence S q , starting from the first to the Pth sampling point, with P as the sampling interval for S q Resample and obtain P groups of resampled data sequences; the qth sliding pth group of resampled data sequences is recorded as S q_p =[x q+p-1 ,x q+p ,…,x q+p+n-1 ,…,x q+p+N ]; where n = 1, 2, ..., N; p = 1, 2, ..., P;
[0028] Calculate each set of resampled data sequence S q_p The spectrum sequence FFT (S q_P ), and add up the spectrum sequences of each group to obtain the sum spectrum sequence F of the data sequence corresponding to the qth sliding observation window q =|FFT(S q_1 )|+|FFT(S q_2 )|+…+|FFT(S q_P )|; where FFT() represents the Fast Fourier Transform of the resampled data sequence; || represents taking the absolute value;
[0029] Detect and record the sum spectrum sequence F q Peak F q max ;
[0030] In the range of q<2T, make sure that F q max The starting position x of the observation window that is the largest and greater than the set threshold q The starting position x of the code element o .
[0031] Optionally, after determining the symbol starting position, the receiving end demodulates the information on the modulated signal into a binary information code using a periodic resampling frequency domain energy detection method, specifically including:
[0032] The receiving end is based on the code element starting position x o , according to the observation window length L, the data sequence Sq Segmentation is performed, and the data sequence of the g-th segment is S g =[x o+(g-1)T+1 ,x o+(g-1)T+2 ,…,x o+gT ];
[0033] For the g-th data sequence S g , starting from the 1st to the Pth sampling points, with P as the sampling interval for S g Resample and obtain P groups of resampled data sequences; record the p-th group of resampled data sequences in the g-th segment as S g_p =[x o+(g-1)T+p ,x o+(g-1)T+1+p, …,x o+(g-1)T+p+N ];
[0034] Calculate each set of resampled data sequence S g_p The spectrum sequence FFT (S g_P ), and add up the spectrum sequences of each group to obtain the spectrum sequence F corresponding to the data of each sliding observation window g =|FFT(S g_1 )|+|FFT(S g_2 )|+…+|FFT(S g_P )|;
[0035] Detect and record the sum spectrum sequence F g Peak F g max ;
[0036] When F g max When the value is greater than the set threshold, it is determined as binary code 1, otherwise it is determined as binary code 0. After the determination is completed, the corresponding binary information code is obtained.
[0037] In a second aspect, the present application also provides a wireless information transmission device, comprising a transmitter and a receiver; the transmitter and the receiver are used to execute the wireless transmission modulation and demodulation method.
[0038] In a third aspect, the present application further provides a transmitting end of a wireless information transmission device, the transmitting end being configured to perform the following steps:
[0039] Obtain the binary information code of the information to be transmitted and set the code element width and transmission bandwidth;
[0040] Generate a multi-component periodic frequency modulation signal according to the symbol width and the transmission bandwidth;
[0041] Modulating a binary information code onto a multi-component periodic frequency modulation signal to generate a modulated signal;
[0042] Adjust the modulated signal to the transmit frequency and transmit at the specified power.
[0043] In a fourth aspect, the present application further provides a receiving end of a wireless information transmission device, the receiving end being configured to perform the following steps:
[0044] Performing frequency conversion and digital processing on the received signal to obtain a digital received signal;
[0045] Detect whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determine the starting position of the code element;
[0046] After determining the starting position of the code element, the information on the modulated signal is demodulated into a binary information code using the periodic resampling frequency domain energy detection method;
[0047] Decode the binary information code to obtain the transmitted information.
[0048] According to the specific embodiments provided in this application, this application discloses the following technical effects:
[0049] The present application provides a wireless transmission modulation and demodulation method, a wireless information transmission device, a transmitter and a receiver. The transmitter generates a multi-component periodic frequency modulation signal according to the code element width and the transmission bandwidth, and modulates the binary information code onto the multi-component periodic frequency modulation signal for transmission. The multi-component periodic frequency modulation signal has the characteristics of frequency domain energy dispersion and low peak power, and has strong energy concentration and strong anti-multipath interference capability after periodic resampling at the receiving end. Therefore, under the conditions of equivalent transmission power, transmission bandwidth and code element rate, the processing gain of the wireless transmission modulation and demodulation method of the present application is greatly improved, and is not affected by multipath interference, and has a strong ability to resist Doppler frequency shift, which greatly improves the wireless transmission distance and reliability of information in complex environments. BRIEF DESCRIPTION OF THE DRAWINGS
[0050] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0051] Figure 1 A flowchart of a wireless transmission modulation and demodulation method;
[0052] Figure 2 The figure is a schematic diagram showing the principle of a wireless transmission modulation and demodulation method. DETAILED DESCRIPTION
[0053] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0054] The purpose of this application is to propose a wireless transmission modulation and demodulation method, a wireless information transmission device, a transmitter and a receiver that are resistant to Doppler frequency shift and multipath interference, so as to improve the wireless transmission distance and reliability of information in complex environments with large path loss and severe Doppler frequency shift and multipath interference.
[0055] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.
[0056] In an exemplary embodiment, the present application provides a wireless transmission modulation and demodulation method. Figure 1 and Figure 2 As shown, the wireless transmission modulation and demodulation method includes the following steps 1 to 8.
[0057] Step 1: The transmitter obtains the binary information code of the information to be transmitted and sets the code element width and transmission bandwidth.
[0058] The transmitter first obtains the information to be transmitted. The information to be transmitted can be various key information that needs to be transmitted due to the activities of people, livestock, or equipment operations in a complex environment, such as alarm information, distress information, emergency command information, safety status information, etc.
[0059] By performing binary encoding on the information to be transmitted, the corresponding binary information code can be obtained. Furthermore, the symbol width T and transmission bandwidth B need to be set according to the transmission environment and transmission rate requirements.
[0060] Step 2: The transmitter generates a multi-component periodic frequency modulation signal based on the symbol width and transmission bandwidth.
[0061] The transmitter generates the Z1-periodic frequency-modulated signals required for transmitting information according to the specified conditions, as a multi-component periodic frequency-modulated signal. Z1 is the number of components and is a positive integer. These Z1-periodic frequency-modulated signals meet the following conditions: equal carrier frequency, bandwidth no greater than the transmission bandwidth B, minimum common period P equal to one-Nth of the symbol width T, and N is a positive integer, typically greater than 32.
[0062] Step 3: The transmitter modulates the binary information code onto the multi-component periodic frequency modulation signal to generate a modulated signal.
[0063] The transmitter modulates the multi-component periodic frequency modulation signal according to the binary information code and the code element width T. The specific process is as follows: when the binary code "1" is transmitted, the Z1 periodic frequency modulation signals generated in step 2 are transmitted for a duration of T; when the binary code "0" is transmitted, no signal is transmitted for a duration of T.
[0064] There are two main ways to transmit multi-component periodic frequency-modulated signals: 1) transmitting the Z1 components (i.e., Z1 periodic frequency-modulated signals) through Z1 different RF channels and antennas, which can avoid power amplifier distortion caused by a large peak-to-average power ratio and reduce the requirements for power amplification; 2) adding the Z1 components and then transmitting them through a single RF channel and antenna can reduce hardware complexity.
[0065] Step 4: The transmitter adjusts the modulated signal to the transmission frequency and transmits it at the specified power.
[0066] That is, the modulated signal generated in step 3 is frequency-converted, adjusted to the transmit frequency, and then transmitted at the specified power. The frequency and power of the transmit signal can be set as needed. After the transmit signal is transmitted through the channel, it is received by the receiver.
[0067] Step 5: The receiving end performs frequency conversion and digitization on the received signal to obtain a digitized received signal.
[0068] The receiving end uses Z2 antennas to receive signals, and performs frequency conversion and digital processing on the received signals. The received signals of each channel are superimposed to obtain the digital received signal S r ; Where Z2 is a positive integer. Specifically, S r =[x1,x2,x3,…,x t ,…]; where the subscript t=1,2,3,… represents the sampling point number, for example, x t It represents the tth sampling point.
[0069] Step 6: The receiving end detects whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determines the starting position of the code element.
[0070] The receiving end determines the observation window length L according to the set code element width T, and makes the observation window length equal to the code element width, that is, L = T. Then, r Perform the starting end detection, the specific process is as follows.
[0071] Step 6.1: Slide the observation window starting position with a sampling point as the step length, and record the data sequence selected by the qth sliding observation window as S q =[x q ,x q+1 ,…,x q+L-1 ].
[0072] Step 6.2: For the selected data sequence S q , starting from the first to the Pth sampling point, with P as the sampling interval for S q Resample and obtain P groups of resampled data sequences; where P is the minimum common period; the qth sliding pth group of resampled data sequences is recorded as S q_p =[x q+p-1 ,x q+p ,…,x q+p+n-1 ,…,x q+p+N ]; where n = 1, 2,…, N; p = 1, 2,…, P.
[0073] Step 6.3: Calculate each set of resampled data sequence S q_p The spectrum sequence FFT (S q_P ), and add up the spectrum sequences of each group to obtain the sum spectrum sequence F of the data sequence corresponding to the qth sliding observation window q =|FFT(S q_1 )|+|FFT(S q_2 )|+…+|FFT(S q_P )|. FFT() represents computing the fast Fourier transform of the resampled data sequence to obtain its corresponding spectrum sequence. || represents taking the absolute value of each element in the resampled data sequence.
[0074] Step 6.4: Detect and record the sum spectrum sequence F q Peak F q max .
[0075] Step 6.5: In the range where the number of observation window slides is less than 2 times the symbol width, that is, in the range of q<2T, determine the value of F q max The starting position x of the observation window that is the largest and greater than the set threshold q The starting position x of the code element o .
[0076] The threshold value can be determined by using the constant false alarm detection principle, the mean absolute variance method, and other methods. o , which means that the digitized received signal contains multi-component periodic frequency modulation signals to be detected.
[0077] Step 7: After the receiving end determines the starting position of the code element, it uses the periodic resampling frequency domain energy detection method to demodulate the information on the modulated signal into a binary information code.
[0078] The demodulation and decoding process specifically includes:
[0079] Step 7.1: The receiver estimates the starting position of the code element xo , according to the observation window length L, the data sequence S q Segmentation is performed, and the data sequence of the g-th segment is S g =[x o+(g-1)T+1 ,x o+(g-1)T+2 ,…,x o+gT ].
[0080] Step 7.2: For the g-th data sequence S g , starting from the 1st to the Pth sampling points, with P as the sampling interval for S g Resample and obtain P groups of resampled data sequences; record the p-th group of resampled data sequences in the g-th segment as S g_p =[x o+(g-1)T+p ,x o+(g-1)T+1+p, …,x o+(g-1)T+p+N ].
[0081] Step 7.3: Calculate each set of resampled data sequence S g_p The spectrum sequence FFT (S g_P ), and add up the spectrum sequences of each group to obtain the spectrum sequence F corresponding to the data of each sliding observation window g =|FFT(S g_1 )|+|FFT(S g_2 )|+…+|FFT(S g_P )|; FFT() represents the calculation of the fast Fourier transform of the resampled data sequence; || represents taking the absolute value of each element in the resampled data sequence.
[0082] Step 7.4: Detect and record the sum spectrum sequence F g Peak F g max .
[0083] Step 7.5: When F g max When the value is greater than the set threshold, it is judged as binary code "1", otherwise it is judged as binary code "0", and the corresponding binary information code is obtained after the judgment is completed.
[0084] After the above demodulation and decoding process, the binary information code of the transmitter is restored.
[0085] Step 8: The receiving end decodes the binary information code to obtain the transmitted information.
[0086] Steps 6-7 above implement multi-component PFMS signal detection using periodic resampling frequency-domain energy detection. This method detects the presence of a communication signal in the channel and performs synchronization alignment. By determining the information contained in each symbol, the modulated signal is demodulated into a binary information code. The receiving end decodes the resulting binary information code to obtain the transmitted information.
[0087] The wireless transmission modulation and demodulation method provided by the present application is based on the advantages of frequency domain energy dispersion and low peak power of multi-component (Z1 components) periodic frequency modulation signals, as well as strong energy concentration and strong anti-multipath interference capability after periodic resampling. It alleviates the problem of insufficient energy utilization in the time and frequency domain of existing wireless signal modulation and demodulation methods, which makes it difficult to provide sufficient modulation gain and the ability to resist multipath interference and environmental interference, resulting in degradation or even failure of wireless communication performance. Under the conditions of equivalent transmission power, transmission bandwidth and code element rate, the processing gain of the wireless transmission modulation and demodulation method of the present application is improved by approximately Z1×Z2 times compared to the chirp spread spectrum modulation non-coherent demodulation method, and is not affected by multipath interference and has strong anti-Doppler frequency shift capability, greatly improving the wireless transmission distance and reliability of information in complex environments.
[0088] In an exemplary embodiment, the present application also provides a wireless information transmission device, including a transmitter and a receiver; the transmitter and the receiver are used to perform the wireless transmission modulation and demodulation method.
[0089] Of course, in other exemplary embodiments, the transmitter and receiver can also be used as independent devices, or separately arranged in different communication devices or computing devices for use. The communication device / computing device can be a server or a terminal. The communication device / computing device includes a processor, memory, an input / output interface, and a communication interface. The processor, memory, and input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the communication device / computing device is used to provide computing and control capabilities. The memory of the communication device / computing device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals via a network connection.
[0090] Therefore, in an exemplary embodiment, the present application further provides a transmitting end of a wireless information transmission device, wherein the transmitting end is configured to perform the following steps:
[0091] Obtain the binary information code of the information to be transmitted and set the code element width and transmission bandwidth;
[0092] Generate a multi-component periodic frequency modulation signal according to the symbol width and the transmission bandwidth;
[0093] Modulating a binary information code onto a multi-component periodic frequency modulation signal to generate a modulated signal;
[0094] Adjust the modulated signal to the transmit frequency and transmit at the specified power.
[0095] In an exemplary embodiment, the present application further provides a receiving end of a wireless information transmission device, wherein the receiving end is configured to perform the following steps:
[0096] Performing frequency conversion and digital processing on the received signal to obtain a digital received signal;
[0097] Detect whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determine the starting position of the code element;
[0098] After determining the starting position of the code element, the information on the modulated signal is demodulated into a binary information code using the periodic resampling frequency domain energy detection method;
[0099] Decode the binary information code to obtain the transmitted information.
[0100] The use of the wireless transmission modulation and demodulation method, wireless information transmission device, transmitter and receiver of the present application can improve the wireless transmission distance and reliability of information in environments with large path loss, Doppler frequency shift and severe multipath interference, and provide an effective and highly reliable technical means for the transmission of status information of people, livestock and equipment in complex environments, especially alarm information.
[0101] It should be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.
[0102] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0103] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.
Claims
1. A wireless transmission modulation and demodulation method, characterized in that: include: The transmitter obtains the binary information code of the information to be transmitted and sets the code element width and transmission bandwidth; The transmitter generates a multi-component periodic frequency modulation signal according to the symbol width and transmission bandwidth; The transmitter generates Z1 periodic frequency modulated signals required for transmitting information according to the set conditions as a multi-component periodic frequency modulated signal; where Z1 is the number of components and Z1 is a positive integer; the Z1 periodic frequency modulated signals meet the following conditions: the carrier frequencies are equal, the bandwidth is no greater than the transmission bandwidth B, and the minimum common period P is one-Nth of the symbol width T; N is a positive integer; The transmitter modulates the binary information code onto the multi-component periodic frequency modulation signal to generate a modulated signal; The transmitter adjusts the modulated signal to the transmission frequency and transmits it at the specified power; The receiving end performs frequency conversion and digital processing on the received signal to obtain a digital received signal; The receiving end detects whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determines the starting position of the code element; After the receiving end determines the starting position of the code element, it uses the periodic resampling frequency domain energy detection method to demodulate the information on the modulated signal into a binary information code; The receiving end decodes the binary information code to obtain the transmitted information.
2. The wireless transmission modulation and demodulation method according to claim 1, wherein: The transmitting end obtains the binary information code of the information to be transmitted and sets the code element width and transmission bandwidth, specifically including: The transmitter obtains the information to be transmitted; Binary encode the information to be transmitted to obtain the corresponding binary information code; The symbol width T and transmission bandwidth B are set according to the transmission environment and transmission rate requirements.
3. The wireless transmission modulation and demodulation method according to claim 2, wherein: The transmitting end modulates the binary information code onto the multi-component periodic frequency modulation signal to generate a modulated signal, specifically including: The transmitter modulates the multi-component periodic frequency modulation signal according to the binary information code and the code element width T; when transmitting the binary code 1, it transmits Z1 periodic frequency modulation signals with a duration of T; when transmitting the binary code 0, it does not transmit a signal for a duration of T.
4. The wireless transmission modulation and demodulation method according to claim 3, wherein: The receiving end performs frequency conversion and digital processing on the received signal to obtain a digital received signal, specifically including: The receiving end uses Z2 antennas to receive signals, and performs frequency conversion and digital processing on the received signals. The received signals of each channel are superimposed to obtain the digital received signal S r =[x1,x2,x3,…,x t ,…]; where the subscript t = 1, 2, 3,… represents the sampling point number; Z2 is a positive integer.
5. The wireless transmission modulation and demodulation method according to claim 4, wherein: The receiving end detects whether there is a multi-component periodic frequency modulation signal to be detected in the digitized received signal and determines the starting position of the code element, specifically including: The receiving end determines the observation window length L according to the set code element width T, and sets the observation window length L = T; To S r Perform the starting end detection, take one sampling point as the starting position of the sliding observation window, and record the data sequence selected by the qth sliding observation window as S q =[x q ,x q+1 ,…,x q+L-1 ]; For the selected data sequence S q , starting from the first to the Pth sampling point, with P as the sampling interval for S q Resample and obtain P groups of resampled data sequences; the qth sliding pth group of resampled data sequences is recorded as S q_p =[x q+p-1 ,x q+p ,…,x q+p+n-1 ,…,x q+p+N ]; where n = 1, 2, ..., N; p = 1, 2, ..., P; Calculate each set of resampled data sequence S q_p The spectrum sequence FFT (S q_P ), and add up the spectrum sequences of each group to obtain the sum spectrum sequence F of the data sequence corresponding to the qth sliding observation window q =|FFT(S q_1 )|+|FFT(S q_2 )|+…+|FFT(S q_P )|; where FFT() represents the Fast Fourier Transform of the resampled data sequence; || represents taking the absolute value; Detect and record the sum spectrum sequence F q Peak F q max ; In the range of q<2T, make sure that F q max The starting position x of the observation window that is the largest and greater than the set threshold q The starting position x of the code element o .
6. The wireless transmission modulation and demodulation method according to claim 5, wherein: After the receiving end determines the starting position of the code element, the information on the modulated signal is demodulated into a binary information code using a periodic resampling frequency domain energy detection method, specifically including: The receiving end is based on the code element starting position x o , according to the observation window length L, the data sequence S q Segmentation is performed, and the data sequence of the g-th segment is S g =[x o+(g-1)T+1 ,x o+(g-1)T+2 ,…,x o+gT ]; For the g-th data sequence S g , starting from the 1st to the Pth sampling points, with P as the sampling interval for S g Resample and obtain P groups of resampled data sequences; record the p-th group of resampled data sequences in the g-th segment as S g_p =[x o+(g-1)T+p ,x o+(g-1)T+1+p, …,x o+(g-1)T+p+N ]; Calculate each set of resampled data sequence S g_p The spectrum sequence FFT (S g_P ), and add up the spectrum sequences of each group to obtain the spectrum sequence F corresponding to the data of each sliding observation window g =|FFT(S g_1 )|+|FFT(S g_2 )|+…+|FFT(S g_P )|; Detect and record the sum spectrum sequence F g Peak F g max ; When F g max When the value is greater than the set threshold, it is determined as binary code 1, otherwise it is determined as binary code 0. After the determination is completed, the corresponding binary information code is obtained.
7. A wireless information transmission device, characterized in that: It comprises a transmitting end and a receiving end; the transmitting end and the receiving end are used to execute the wireless transmission modulation and demodulation method according to any one of claims 1 to 6.
8. A wireless information transmission device, characterized in that: Includes the following modules: A module for obtaining the binary information code of the information to be transmitted and setting the code element width and transmission bandwidth; A module for generating a multi-component periodic frequency modulation signal according to a symbol width and a transmission bandwidth; Specifically, Z1 periodic frequency modulation signals required for transmitting information are generated according to set conditions as multi-component periodic frequency modulation signals; where Z1 is the number of components and Z1 is a positive integer; the Z1 periodic frequency modulation signals meet the following conditions: the carrier frequencies are equal, the bandwidth is not greater than the transmission bandwidth B, and the minimum common period P is one Nth of the symbol width T; N is a positive integer; A module for modulating a binary information code onto a multi-component periodic frequency modulation signal to generate a modulated signal; A module used to adjust the modulated signal to the transmission frequency and transmit it at a specified power.
9. A wireless information transmission device, characterized in that: Includes the following modules: A module for performing frequency conversion and digital processing on a received signal to obtain a digital received signal; A module for detecting whether a multi-component periodic frequency modulation signal to be detected exists in a digitized received signal and determining a symbol starting position; wherein the multi-component periodic frequency modulation signal refers to Z1 periodic frequency modulation signals required for transmitting information generated according to set conditions, where Z1 is the number of components and Z1 is a positive integer; the Z1 periodic frequency modulation signals satisfy the following conditions: equal carrier frequency, bandwidth not greater than the transmission bandwidth B, minimum common period P is one-Nth of the symbol width T, and N is a positive integer; A module for demodulating the information on the modulated signal into a binary information code using a periodic resampling frequency domain energy detection method after determining the starting position of the code element; A module used to decode binary information codes to obtain the transmitted information.
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Patent Citations
Information modulation and demodulation method of high frequency band utilization rate
CN1494284A