Frequency selection method based on medium and long wave communication, terminal device and storage medium

Abstract

The embodiment of the application discloses a frequency selection method based on medium-long wave communication, a terminal device and a storage medium, which are used for reducing the message transmission rate to improve the demodulation sensitivity, so as to select a desired frequency point. The method of the embodiment of the application comprises the following steps: receiving radio frequency signals corresponding to a first frequency point transmitted at least twice through a first preset number of channels; screening a second preset number of radio frequency signals from the first preset number of radio frequency signals, wherein the second preset number is less than the first preset number; feeding back an ACK signal; and receiving service data transmitted according to the ACK signal.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication, in particular to a frequency selection method based on medium-long wave communication, a terminal device and a storage medium. BACKGROUND

[0002] In the actual application of the prior art, a few frequency points are often agreed upon. Although this method shortens the scanning time, it may miss better frequency points, and even the selected frequency points cannot establish a communication link, so that the communication effect cannot be guaranteed. The selection of experience frequency points depends on geographical location, personal experience and other factors, and must be pre-stationed to explore to establish experience frequency points, which cannot adapt to the changing environment. SUMMARY

[0003] The embodiments of the present application provide a frequency selection method based on medium-long wave communication, a terminal device and a storage medium, which are used to improve the demodulation sensitivity by reducing the message transmission rate, so as to select the desired frequency point.

[0004] The first aspect of the present application provides a frequency selection method based on medium-long wave communication, which can include:

[0005] Receiving a radio frequency signal corresponding to a first frequency point sent at least twice through a first preset number of channels;

[0006] From the first preset number of radio frequency signals, a second preset number of radio frequency signals are selected, and the second preset number is less than the first preset number;

[0007] Feedback ACK signal;

[0008] Receiving service data sent according to the ACK signal.

[0009] The second aspect of the present application provides a frequency selection method based on medium-long wave communication, which can include:

[0010] Sending a radio frequency signal corresponding to a first frequency point at least twice, the radio frequency signal corresponding to the first frequency point being used to select a radio frequency signal;

[0011] Receiving an ACK signal;

[0012] Sending service data according to the ACK signal.

[0013] The third aspect of the present application provides a terminal device, which can include:

[0014] The transceiver module is configured to receive a radio frequency signal corresponding to a first frequency point sent at least twice through a first preset number of channels;

[0015] The processing module is configured to screen a second preset number of radio frequency signals from a first preset number of radio frequency signals, the second preset number being less than the first preset number.

[0016] The transceiver module is further configured to feed back an acknowledgement (ACK) signal and receive service data sent according to the ACK signal.

[0017] The fourth aspect of the present application provides a terminal device, which can include:

[0018] The transceiver module is configured to send a radio frequency signal corresponding to a first frequency point at least twice, the radio frequency signal corresponding to the first frequency point being used for screening radio frequency signals, receive an acknowledgement (ACK) signal, and send service data according to the ACK signal.

[0019] The fifth aspect of the present application provides a terminal device, which can include:

[0020] A memory storing executable program codes;

[0021] A processor and a transceiver coupled to the memory;

[0022] The processor invokes the executable program codes stored in the memory, so that the processor and the transceiver perform the method according to the first aspect or the second aspect of the present application correspondingly.

[0023] In yet another aspect, the embodiments of the present application provide a computer readable storage medium, including instructions, when the instructions are run on a processor, causing the processor to perform the method according to the first aspect or the second aspect of the present application.

[0024] In yet another aspect, the embodiments of the present application disclose a computer program product, when the computer program product is run on a computer, causing the computer to perform the method according to the first aspect or the second aspect of the present application.

[0025] In yet another aspect, the embodiments of the present application disclose an application publishing platform, the application publishing platform being used for publishing a computer program product, when the computer program product is run on a computer, causing the computer to perform the method according to the first aspect or the second aspect of the present application.

[0026] From the above technical solutions, the embodiments of the present application have the following advantages:

[0027] In the embodiment of the present application, the master terminal device sends the radio frequency signal corresponding to the first frequency point at least twice, the radio frequency signal corresponding to the first frequency point is used for screening the radio frequency signal; the slave terminal device receives the radio frequency signal corresponding to the first frequency point sent at least twice through the first preset number of channels; the slave terminal device screens the second preset number of radio frequency signals from the first preset number of radio frequency signals, the second preset number is less than the first preset number; the slave terminal device feeds back the acknowledgement ACK signal; the master terminal device receives the acknowledgement ACK signal; the master terminal device sends the service data according to the ACK signal; and the slave terminal device receives the service data sent according to the ACK signal. By reducing the message transmission rate, the demodulation sensitivity is improved, so that the desired frequency point is selected. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments and the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained from these drawings.

[0029] Figure 1 A schematic diagram for the master terminal device sending the frequency point and the slave terminal device all frequency point cycle scanning waiting in the prior art;

[0030] Figure 2 An embodiment schematic diagram of the frequency selection method based on medium and long wave communication in the embodiment of the present application;

[0031] Figure 3A A schematic diagram of full frequency band real-time waiting scanning in the embodiment of the present application;

[0032] Figure 3B A basic link flow schematic diagram between the master terminal device and the slave terminal device in the embodiment of the present application;

[0033] Figure 4 Another embodiment schematic diagram of the frequency selection method based on medium and long wave communication in the embodiment of the present application;

[0034] Figure 5A A schematic diagram of two pieces of FPGA connected by software direct connection in the embodiment of the present application;

[0035] Figure 5B A schematic diagram of two pieces of FPGA connected by software direct connection in the embodiment of the present application;

[0036] Figure 5C A basic flowchart of processing the received radio frequency signal in the embodiment of the present application;

[0037] Figure 5D A schematic diagram of the sampling algorithm used by the terminal device in the embodiment of the present application;

[0038] Figure 5E Figure 1 is a schematic diagram of interface connection among channel board, service board and master control board included in terminal device in an embodiment of the present application;

[0039] Figure 5F Figure 2 is a schematic diagram of connection of two FPGAs with ADC and DAC in an embodiment of the present application;

[0040] Figure 5G Figure 3 is a schematic diagram of hardware connection in terminal device in an embodiment of the present application;

[0041] Figure 5H Figure 4 is a schematic diagram of interface connection of hardware in terminal device in an embodiment of the present application;

[0042] Figure 6 Figure 5 is a schematic diagram of an embodiment of terminal device in the present application;

[0043] Figure 7 Figure 6 is a schematic diagram of another embodiment of terminal device in the present application;

[0044] Figure 8 Figure 7 is a schematic diagram of another embodiment of terminal device in the present application. DETAILED DESCRIPTION

[0045] The embodiment of the present application provides a frequency selection method based on medium-long wave communication, a terminal device and a storage medium, which are used for reducing message transmission rate to improve demodulation sensitivity, so as to select a desired frequency point.

[0046] In order for those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all should belong to the scope of protection of the present application.

[0047] The traditional communication link establishment mode of medium-long wave communication is that the master terminal device sends a single frequency point fixedly, and the slave terminal device scans and waits. Since the waveform is relatively long (signaling of 12.5 byte / min needs 200 seconds), the master terminal device needs to send for a long time to ensure that the slave terminal device receives the frequency point matched with the transmission frequency point of the master terminal device. This is a very severe test for the master terminal device with high power, and it is also easy to be detected by the enemy according to the continuous power. For example, as shown in FIG. 1, it is a schematic diagram of the master terminal device sending a frequency point and the slave terminal device cyclically scanning and waiting for all frequency points in the prior art. Figure 1

[0048] ​In view of the above actual situation, in the actual application of the prior art, a few frequency points are often agreed upon. Although this method shortens the scanning time, it may miss better frequency points, and even the selected frequency points cannot establish a chain communication, so that the communication effect cannot be guaranteed. The selection of the experience frequency point depends on the geographical location, personal experience and other factors, and must be pre-stationed to explore to establish the experience frequency point, which cannot adapt to the changing environment.

[0049] According to the use requirements of the medium-long wave communication system, in combination with the strong signal processing technology, the application proposes an intelligent frequency selection technology of the medium-long wave terminal device to realize a more reliable and efficient communication scheme. In the embodiment of the application, the demodulation sensitivity is improved by reducing the message transmission rate. Since the technology is mainly used for weak signal demodulation, it is limited by frequency and message type, and the frequency selection time of the application is relatively long; although the message transmission time is relatively long, extremely weak signals can be stably and reliably received, and even signals below noise, such as 30 dB, can be received.

[0050] The technical scheme of the application will be further described below in the form of embodiments. As shown in FIG. 1, it is an embodiment schematic diagram of the frequency selection method based on the medium-long wave communication in the embodiment of the application, which can include: Figure 2

[0051] 201, at least twice sending a radio frequency signal corresponding to a first frequency point, the radio frequency signal corresponding to the first frequency point is used for screening the radio frequency signal.

[0052] Receiving a first preset number of radio frequency signals corresponding to the first frequency point sent at least twice through a first preset number of channels.

[0053] The first terminal device, that is, the master terminal device, sends the radio frequency signal corresponding to the first frequency point at least twice, and the second terminal device, that is, the slave terminal device, receives the radio frequency signal corresponding to the first frequency point sent at least twice through the first preset number of channels.

[0054] Optionally, the first frequency point is selected by the master terminal device according to experience data.

[0055] Optionally, the experience data includes at least one of historical spectrum data, experience available frequency band, and geographical location. Optionally, the experience data can also include other information.

[0056] ​Exemplarily, the frequency of the middle-long wave is 200 KHz-400 KHz (66.6 frequency points in total scanning), and for the convenience of calculation, 64 frequency points are usually used for calculation, and the resource-rich condition can be extended to 66 ways. The application is calculated by multiple Field Programmable Gate Array (FPGA) parallel computing, and the channels of the full frequency band are parallel standby. The master terminal device needs to continuously send two radio frequency signals or more than two radio frequency signals, and the terminal device can receive the radio frequency signal.

[0057] 202、From the first preset number of radio frequency signals, a second preset number of radio frequency signals are screened out, and the second preset number is less than the first preset number.

[0058] Exemplarily, the terminal device is comprehensively evaluated, and some channels are excluded through experience information and current spectrum monitoring information, etc. For example, 24, 20, 16, etc. Information is screened out to realize full-band scanning. As shown in Figure 3A

[0059] 203, feedback ACK signal.

[0060] Receive ACK signal.

[0061] The terminal device feeds back the ACK signal to the master terminal device, and the master terminal device receives the ACK signal.

[0062] 204, according to the ACK signal to send service data.

[0063] Receive service data sent according to the ACK signal.

[0064] The master terminal device can send service data according to the received ACK signal, and the terminal device receives the service data sent by the master terminal device.

[0065] Exemplarily, as shown in Figure 3B

[0066] ​​In the embodiment of the present application, the master terminal device transmits the radio frequency signal corresponding to the first frequency point at least twice, the radio frequency signal corresponding to the first frequency point is used for screening the radio frequency signal; the slave terminal device receives the radio frequency signal corresponding to the first frequency point transmitted at least twice through the first preset number of channels; the slave terminal device screens the second preset number of radio frequency signals from the first preset number of radio frequency signals, the second preset number is less than the first preset number; the slave terminal device feeds back the acknowledgement ACK signal; the master terminal device receives the acknowledgement ACK signal; the master terminal device transmits the service data according to the ACK signal; and the slave terminal device receives the service data transmitted according to the ACK signal. By reducing the message transmission rate, the demodulation sensitivity is improved, so that the desired frequency point is selected.

[0067] As shown in Figure 4 , it is another embodiment schematic diagram of the frequency selection method based on medium and long wave communication in the embodiment of the present application, which can include:

[0068] 401, transmitting the radio frequency signal corresponding to the first frequency point at least twice, the radio frequency signal corresponding to the first frequency point is used for screening the radio frequency signal.

[0069] 402, screening the second preset number of radio frequency signals from the first preset number of radio frequency signals, the second preset number is less than the first preset number.

[0070] Optionally, the method is applied to a terminal device, the terminal device includes a channel board and a service board, the service board includes a first FPGA and a second FPGA, one end of the first FPGA is connected with an analog-to-digital converter ADC, the other end is connected with a digital-to-analog converter DAC, the pin of the second FPGA is set as high resistance, the input and output pins of the first FPGA and the second FPGA are consistent;

[0071] The screening of the second preset number of radio frequency signals from the first preset number of radio frequency signals can include: processing the first preset number of radio frequency signals by the first analog-to-digital converter ADC through the channel board to obtain the first preset number of intermediate frequency signals; transmitting the first preset number of intermediate frequency signals to the second FPGA through the first FPGA; screening the second preset number of intermediate frequency signals from the first preset number of intermediate frequency signals through the first FPGA and the second FPGA.

[0072] Understandably, since the pre-selected frequency points cannot be guaranteed to be evenly distributed across the two FPGAs, the main controller needs to continue distributing tasks equally between the two FPGAs. Simultaneously, to reduce the complexity of interface transmission, both FPGAs simultaneously implement functions such as channel down-conversion across the entire frequency band, directly transmitting the RF signal from FPGA1 to FPGA2 via an analog-to-digital converter (ADC). The following scheme ensures the consistency of the FPGA program: The input and output pins of the two FPGAs must be completely identical. For example... Figure 5A The diagram shown is a schematic of a software pass-through connection between two FPGAs in an embodiment of this application.

[0073] Since this application uses two FPGAs, but only one digital-to-analog converter (DAC) is needed, to ensure consistency of the FPGA program loading file, the corresponding DAC pin can be set to high impedance. The same general-purpose input / output (GPIO) pins can be pulled high or low to serve as the device's identity (ID), facilitating subsequent debugging and protocol simplification. Figure 5B The diagram shown is a schematic of two FPGAs connected to a DAC in an embodiment of this application.

[0074] It should be noted that the FPGA in this application is a Zynq chip, replacing the FPGA and Digital Signal Processing (DSP) chips in the prior art.

[0075] Currently, the main solution used in China is 7K325T+DSP (TI6416). This application's technical solution: Zynq7045 uses a PS (Power Sequencer) to replace digital signal processing (DSP) for various waveforms on shortwave, and its computing power can meet the requirements.

[0076] Zynq: Generally refers to Xilinx's ZYNQ series chips, which is the industry's first scalable processing platform launched by Xilinx, designed to provide the required processing and computing performance levels for high-end embedded applications such as video surveillance, automotive driver assistance, and factory automation.

[0077] 403. The second preset number of intermediate frequency signals are evenly divided between the first FPGA and the second FPGA, and the signals are detected using Fast Fourier Transform (FFT) to obtain the signal detection results.

[0078] It can be understood that the channel board transmits intermediate frequency signals to the service board from the terminal device, and the bandwidth of the intermediate frequency signals can be set to 200 KHz, so that the wideband reception of medium and long waves is realized. Through wideband reception and multi-channel processing, channel down-conversion and down-sampling of the full frequency band are realized. The basic signal processing flow is: radio frequency signal→channel board→ADC→intermediate frequency signal→multi-channel down-conversion (mixing+direct data control (DDC)).

[0079] As Figure 5C shown, it is a basic flow chart for processing the received radio frequency signals in the embodiment of the application. The following describes a basic flow of processing the received radio frequency signals from the terminal device, as follows:

[0080] 1. The radio frequency signals are divided into two paths by ADC and given to two FPGAs at the same time;

[0081] 2. 64-channel down-conversion processing is performed at the same time on both sides (although some unnecessary repeated resources are consumed, but the workload of interface development is reduced);

[0082] 3. Through actual measurement spectrum and historical experience, for example, the top 24 channels are selected, and 12 channels are evenly distributed to the two FPGAs;

[0083] 4. If the experience data and spectrum are too different, less than 12 channels are selected, which reduces the probability of false alarm in subsequent detection (here, it needs to rely on actual experience accumulation);

[0084] 5. The FPGA performs fast Fourier transform (FFT) spectrum sensing and signal detection, and sends the signal detection result to the processing system (PS) side.

[0085] The central processing unit (CPU) continues to configure the signal detection result on the PS side; the PS side can report the decoded signal to the CPU; and the FFT data is transferred to the CPU through the PS.

[0086] In Figure 5C , MIX: mixer.

[0087] PS side decoding: the PS (Processing System) is the part of the ARM (Advanced RISC Machines) SOC (System on Chip) independent of the FPGA, and the PS side decoding means that the decoding process is completed in the ARM.

[0088] It can be understood that the terminal device further comprises a main control board, and the main control board comprises a CPU.

[0089] 404、selecting a target channel according to the signal detection result.

[0090] Optionally, the target channel is an optimal channel.

[0091] 405、changing the center frequency of the channel board to correspond to the target channel.

[0092] 406、feeding back an ACK signal.

[0093] 407、sending service data according to the ACK signal.

[0094] receiving the service data sent according to the ACK signal.

[0095] Optionally, the receiving the service data sent according to the ACK signal can comprise receiving the service data sent according to the ACK signal through the target channel.

[0096] Optionally, the receiving the first frequency point corresponding to the radio frequency signal sent at least twice through the first preset number of channels by the terminal device can comprise receiving the first frequency point corresponding to the radio frequency signal sent at least twice through the first preset number of channels by the terminal device using a 4-fold oversampling algorithm.

[0097] The receiving the service data sent according to the ACK signal by the terminal device can comprise receiving the service data sent according to the ACK signal by the terminal device using an 8-fold oversampling algorithm.

[0098] It can be understood that, in the service frequency selection link establishment, in order to ensure more parallel channel detection, a 4-fold oversampling algorithm is used for guaranteeing. After the frequency selection is determined, the channel is specified to a single down-conversion, and 8-fold oversampling baseband data is used to realize signal detection. At this time, the center frequency of the channel board also needs to be changed to adapt to the narrowband filtering of the single down-conversion analog part on the channel board. As shown in Figure 5D the sampling algorithm used by the terminal device in the embodiment of the application is a schematic diagram.

[0099] PL side: programmable logic (Progarmmable Logic), that is, the FPGA part.

[0100] Optionally, the terminal device comprises a channel board, a service board and a main control board; the channel board, the service board and the main control board are connected through a serial port.

[0101] As Figure 5EAs shown, it is a schematic diagram of interface connection among channel board, service board and main control board included in terminal device in the embodiment of the application. The interface connection diagram based on core devices such as FPGA and zynq is shown as 5E.

[0102] Optionally, the second preset number of channel frequencies is 50 byte / min or 11 byte / min.

[0103] It can be understood that the terminal device scans at 50 byte / min, for example, 12 (50 byte / min) frequencies are real-time guarded from the terminal device (it can also be configured to scan at 11 byte / min), and the rate selection can be selected according to actual test effect, which is not limited here.

[0104] Based on the exclusion of corresponding frequencies based on local position, the range can be greatly reduced, and the detection can also be changed to 8-way processing per FGPA, which is more practical. (Considering the scheme demonstration, the more the number of parallel detection effects, the better) In order to improve the throughput, the frequency is changed preferentially, and the medium and long waves do not use 12.5 byte / min of this rate (which can be configured according to test requirements).

[0105] As shown in Figure 5F As shown in the embodiment of the application, it is a schematic diagram of connection of two FPGAs and ADC and DAC. Since the signal detection resource is the most critical in the application, each FPGA can only process 12-way signal detection, if the frequency band is divided into upper and lower halves, there is no guarantee that the data to be detected can be evenly distributed on the two FPGAs. Through the interface, the IQ data of the corresponding channel is converted, which increases the debugging workload. Therefore, both of the two FPGAs realize channel filtering of the full frequency band, and the detection task of the two FPGAs is allocated by the main control to achieve the purpose of load balancing. Therefore, the ADC needs to be connected to the two FPGAs completely. However, the transmitting DAC only needs to be connected to one FPGA.

[0106] Among them, IQ data: the data of the IQ signal obtained after the signal is IQ modulated, in essence, the IQ signal is the amplitude of the pair of signals I and Q modulating the orthogonal Cos and Sin components, and the sum of the two can express any modulation of amplitude and phase.

[0107] Next, a brief comparison of chip Z7045 and Z7100 resources is made (for easy expansion, debugging allowance is reserved), as shown in Table 1:

[0108]

[0109] Table 1

[0110] Z7100 logic resources are 1.26 times of Z7045, Z7100 storage resources are 1.38 times of Z7045. Z7100 can make moderate expansion in the case of Z7045 resource shortage, but if the computing amount needs to be multiplied, the device must be increased (Z7100 and Z7045 Pin-to-Pin compatible, integrated replacement over 2HF).

[0111] BRAM: Block RAM, Block Random Access Memory, block random access memory. After programming configuration is carried out on BRAM, the storage function can be realized. BRAM is arranged in the form of an array in the FPGA, and is the main part of the FPGA to realize various storage functions, and is a true double read / write port synchronous RAM.

[0112] As shown in Figure 5G , it is a schematic diagram of hardware connection in the terminal device in the embodiment of the application. As shown in Figure 5H , it is a schematic diagram of hardware interface connection in the terminal device in the embodiment of the application.

[0113] 1. The channel board provides a clock signal through a 1:4 interface (guaranteeing amplitude);

[0114] 2. The black bold line represents a 16-bit low voltage differential signal (Low Voltage Differential Signaling, LVDS);

[0115] The ADC from 7045-A is transmitted to 7045-B, the 7045-B code is the same as 7045-A, and the output pin hardware is suspended.

[0116] 3. The 7010 and the service board interact through a 16-bit LVDS signal, and the hardware pulls up and down through the pin as the ID number of the FPGA, which can maintain the unity of the code;

[0117] 4. The new board hopes to increase some information feedback from the channel board AGC to the service board (dotted GPIO).

[0118] The interface between the main control board, the service board and the channel board in the terminal device is briefly described as follows:

[0119] (1) Main control board → service board (list interface types)

[0120] Tx terminal information to be sent by the main control board to the service board PS side;

[0121] Cfg The main control board configures the detection channel mapping relationship of the service board PL side and can close the switch;

[0122] Cfg master board configuration business board mode of operation - is mainly mapping detection module to 8 times the sample point detection module.

[0123] (2) master board < business board

[0124] Business board reported to the master board PS side local noise;

[0125] Rx business board demodulation information through PS to report to the master PS;

[0126] Business board reported to the master board PTT information. Among them, the PTT button is a button to control the transmission, and when there is a signal (usually connected to the ground), the transmitter is converted from standby to transmission.

[0127] (3) master board and channel board (need business board relay)

[0128] Master board control channel board switching to narrowband filter mode (design to switch frequency) pure wideband does not need to switch mode, set the success of the automatic error correction (ARQ) need to feedback to the master board.

[0129] It can be understood that the following is an example of the technical solutions of the present application.

[0130] As shown in Table 2, for single channel resource, resource statistics using 8 times oversampling algorithm.

[0131] slice DSP BRAM (36 Kb) Overall 21000-6000 180 277-73 11 byte / min detection 1600 22 43 50 byte / min detection 1600 22 43 180 byte / min detection 1600 22 20 360 byte / min detection 1600 22 11 720 byte / min detection 1600 22 11 DUC 1000 32 9 DDC 3000 34 22

[0132] Table 2

[0133] Explanation: The lowest two detection resources, the RAM of the cache data is 36.5 (the debug resource occupation in the above table). Reduce the sampling rate by one, and use the RAM according to 19.

[0134] It can be understood that in the multi-channel parallel computing resource estimation, in order to improve the use efficiency of the device, the original 8 times oversampling detection scheme can be changed to 4 times oversampling (the performance is expected to be lost by 0.5 dB), and for the whole waveform system scene, this performance has little effect on the distance test.

[0135] Optionally, the working master clock of the FPGA is 157.2864MHz.

[0136] The 9.6K symbol used in multipath detection, and there are 8192 clks between each symbol. The number of multiplexed paths for each set of detection resources is 8192 / 1024 (the FFT length used by the algorithm) = 8 paths. If all the detection is performed using 12.5 bytes / min, then the number of multiplexed paths for each resource is 8*8 = 64 paths. There is no additional cost for the logic resources, and the problem to be solved is the storage problem.

[0137] In the embodiment of the present application, the master terminal device sends the radio frequency signal corresponding to the first frequency point at least twice, and the radio frequency signal corresponding to the first frequency point is used for screening the radio frequency signal; the slave terminal device screens the second preset number of radio frequency signals from the first preset number of radio frequency signals, and the second preset number is less than the first preset number; the slave terminal device divides the second preset number of intermediate frequency signals by the first FPGA and the second FPGA, and uses fast Fourier transform (FFT) to perform signal detection to obtain a signal detection result; the slave terminal device selects a target channel according to the signal detection result; the slave terminal device changes the center frequency of the channel board to correspond to the target channel; the slave terminal device feeds back an acknowledgement (ACK) signal; and the master terminal device sends service data according to the ACK signal. That is, in the present application, the slave terminal device can select a target channel by referring to experience data, for example, selecting a target channel by referring to experience frequency. The frequency selection is more accurate, and the frequency selection efficiency of the prior art in the same band is higher and faster. Since the medium and long wave mainly communicates through ground wave, its special communication property causes many factors such as different weather, seasons, morning and evening, and surrounding environment to have certain influence on its frequency selection characteristics. The present scheme can effectively overcome the working frequency band characteristics, and accurately and quickly select the best frequency point.

[0138] As shown in Figure 6 , it is an embodiment schematic diagram of the terminal device in the embodiment of the present application, which can include:

[0139] The transceiver module 601 is configured to receive the radio frequency signal corresponding to the first frequency point sent at least twice through the first preset number of channels.

[0140] The processing module 602 is configured to screen the second preset number of radio frequency signals from the first preset number of radio frequency signals, and the second preset number is less than the first preset number.

[0141] The transceiver module 601 is further configured to feed back an acknowledgement (ACK) signal, and receive service data sent according to the ACK signal.

[0142] Optionally, the terminal device includes a channel board and a service board. The service board includes a first FPGA and a second FPGA. One end of the first FPGA is connected to an analog-to-digital converter (ADC), and the other end is connected to a digital-to-analog converter (DAC). The pins of the second FPGA are set to high impedance. The input and output pins of the first FPGA and the second FPGA are the same.

[0143] The processing module 602 is specifically used to process the first preset number of radio frequency signals through the channel board using the first analog-to-digital converter (ADC) to obtain a first preset number of intermediate frequency signals; to pass the first preset number of intermediate frequency signals through the first FPGA to the second FPGA; and to filter out a second preset number of intermediate frequency signals from the first preset number of intermediate frequency signals through the first FPGA and the second FPGA.

[0144] Optionally, the processing module 602 is further configured to divide the second preset number of intermediate frequency signals equally between the first FPGA and the second FPGA, perform signal detection using Fast Fourier Transform (FFT), obtain signal detection results, select a target channel based on the signal detection results, and change the center frequency of the channel board to correspond to the target channel.

[0145] The transceiver module 601 is specifically used to receive service data sent according to the ACK signal through the target channel.

[0146] Optionally, the transceiver module 601 is specifically used to receive the radio frequency signal corresponding to the first frequency point transmitted at least twice through a first preset number of channels using a 4x oversampling algorithm;

[0147] The transceiver module 601 is specifically used to receive service data sent according to the ACK signal using an 8x oversampling algorithm.

[0148] Optionally, the channel frequency of the second preset number is 50 bytes / min or 11 bytes / min.

[0149] Optionally, the terminal equipment includes a channel board, a service board, and a main control board;

[0150] The channel board, the service board, and the main control board are connected via a serial port.

[0151] like Figure 7 The diagram shown is a schematic representation of another embodiment of the terminal device in this application, which may include:

[0152] The transceiver module 701 is used to transmit a radio frequency signal corresponding to a first frequency point at least twice, the radio frequency signal corresponding to the first frequency point being used to filter radio frequency signals; receive an acknowledgment (ACK) signal; and transmit service data according to the ACK signal.

[0153] Optionally, the first frequency point is selected based on empirical data, which includes at least one of historical spectrum data, empirically available frequency bands, and geographical location.

[0154] like Figure 8 The diagram shown is a schematic representation of another embodiment of the terminal device in this application, which may include:

[0155] Figure 8 This is a block diagram illustrating a portion of the structure of a mobile phone related to the terminal device provided in an embodiment of the present invention. (Reference) Figure 8 The mobile phone includes components such as a radio frequency (RF) circuit 810, a memory 820, an input unit 830, a display unit 840, a sensor 850, an audio circuit 860, a wireless fidelity (Wi-Fi) module 870, a processor 880, and a power supply 890. Those skilled in the art will understand that... Figure 8 The mobile phone structure shown does not constitute a limitation on the mobile phone and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0156] The following is combined Figure 8 A detailed introduction to each component of a mobile phone:

[0157] The RF circuit 810 can be used for receiving and sending signals in the process of information or communication, especially, receiving the downlink information from the base station and processing by the processor 880; in addition, sending the uplink data to the base station. Generally, the RF circuit 810 includes but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc. In addition, the RF circuit 810 can also communicate with the network and other devices through wireless communication. The above wireless communication can use any communication standard or protocol, including but not limited to global system for mobile communication (GSM), general packet radio service (GPRS), code division multiple access (CDMA), wideband code division multiple access (WCDMA), long term evolution (LTE), email, short messaging service (SMS), etc.

[0158] The memory 820 can be used to store software programs and modules, and the processor 880 can execute various function applications and data processing of the mobile phone by running the software programs and modules stored in the memory 820. The memory 820 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application program required by a function (such as a sound playing function, an image playing function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory 820 can include a high-speed random access memory, and can also include a non-volatile memory, for example, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device.

[0159] The input unit 830 can be used to receive input digital or character information, and to generate key signal inputs used for user settings and function controls of the mobile phone. Specifically, the input unit 830 can include a touch panel 831 and other input devices 832. The touch panel 831, also called a touch screen, can collect touch operations (such as operations of a user using a finger, a stylus, or any suitable object or accessory on or near the touch panel 831) of the user on or near it, and drive the corresponding connection device according to the pre-set program. Optionally, the touch panel 831 can include two parts, a touch detection device and a touch controller. The touch detection device detects the touch position of the user and detects the signal generated by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into touch coordinates, and sends it to the processor 880, and can also receive commands from the processor 880 and execute them. In addition, the touch panel 831 can be implemented in various types such as resistive, capacitive, infrared, and surface acoustic wave. In addition to the touch panel 831, the input unit 830 can also include other input devices 832. Specifically, the other input devices 832 can include one or more of a physical keyboard, function keys (such as volume control keys, on / off keys, etc.), trackballs, mice, joysticks, etc.

[0160] The display unit 840 can be used to display information input by the user or information provided to the user, as well as various menus of the mobile phone. The display unit 840 can include a display panel 841, which can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc. Further, the touch panel 831 can cover the display panel 841, and when the touch panel 831 detects a touch operation on or near it, it transmits to the processor 880 to determine the type of touch event, and then the processor 880 provides corresponding visual output on the display panel 841 according to the type of touch event. Although in the above description, the touch panel 831 and the display panel 841 are implemented as two independent components to realize the input and output functions of the mobile phone, in some embodiments, the touch panel 831 and the display panel 841 can be integrated to realize the input and output functions of the mobile phone. Figure 8

[0161] ​The phone can also include at least one sensor 850, such as an optical sensor, a motion sensor, and other sensors. Specifically, the optical sensor can include an ambient light sensor to adjust the brightness of the display panel 841 according to the brightness of ambient light, and a proximity sensor to turn off the display panel 841 and / or the backlight when the phone is moved to the ear. As one of the motion sensors, the accelerometer sensor can detect the magnitude and direction of the acceleration in each direction (generally three axes), and when at rest, it can detect the magnitude and direction of gravity, which can be used for applications that identify the phone posture (such as switching between landscape and portrait screens, related games, magnetometer posture calibration), vibration recognition related functions (such as pedometer, tapping), and the like. As for other sensors that the phone can also be configured, such as a gyroscope, a barometer, a hygrometer, a thermometer, an infrared sensor, and the like, they will not be described here.

[0162] The audio circuit 860, the speaker 861, and the microphone 862 can provide an audio interface between the user and the phone. The audio circuit 860 can convert the received audio data into an electrical signal, transmit it to the speaker 861, and convert it into a sound signal output by the speaker 861; on the other hand, the microphone 862 converts the collected sound signal into an electrical signal, which is received by the audio circuit 860 and converted into audio data, which is then processed by the processor 880 and transmitted to, for example, another phone via the RF circuit 810, or output to the memory 820 for further processing.

[0163] Wi-Fi belongs to a short-range wireless transmission technology. The phone can help users send and receive emails, browse web pages, and access streaming media through the Wi-Fi module 870, which provides users with wireless broadband Internet access. Although Figure 8 The Wi-Fi module 870 is shown, but it is understood that it does not belong to the necessary components of the phone, and can be omitted as needed without changing the essence of the application.

[0164] The processor 880 is the control center of the phone, which connects all parts of the phone through various interfaces and lines, executes various functions of the phone and processes data by running or executing software programs and / or modules stored in the memory 820, and calling data stored in the memory 820, thereby monitoring the whole phone. Optionally, the processor 880 can include one or more processing units; preferably, the processor 880 can integrate an application processor and a modem processor, wherein the application processor mainly processes the operating system, user interface, and application programs, and the modem processor mainly processes wireless communication. It is understood that the above-mentioned modem processor can also not be integrated into the processor 880.

[0165] The mobile phone further includes a power supply 890 (such as a battery) for supplying power to various components, and preferably, the power supply is logically connected to the processor 880 through a power management system, so that the power management system can realize functions such as charge management, discharge management, and power consumption management.

[0166] Although not shown, the mobile phone can further include a camera, a Bluetooth module, and the like, which will not be described here.

[0167] In an embodiment of the present application, the RF circuit 810 is configured to receive, through a first preset number of channels, radio frequency signals corresponding to a first frequency point transmitted at least twice.

[0168] The processor 880 is configured to filter, from the first preset number of radio frequency signals, a second preset number of radio frequency signals, the second preset number being less than the first preset number.

[0169] The RF circuit 810 is further configured to feed back an ACK signal and receive service data transmitted according to the ACK signal.

[0170] Optionally, the terminal device includes a channel board and a service board, the service board includes a first FPGA and a second FPGA, one end of the first FPGA is connected to an analog-to-digital converter ADC, and the other end is connected to a digital-to-analog converter DAC, pins of the second FPGA are set to high resistance, and input and output pins of the first FPGA and the second FPGA are consistent.

[0171] The processor 880 is specifically configured to process, through the channel board, the first preset number of radio frequency signals by using the first analog-to-digital converter ADC to obtain a first preset number of intermediate frequency signals, transmit the first preset number of intermediate frequency signals to the second FPGA through the first FPGA, and filter, from the first preset number of intermediate frequency signals, a second preset number of intermediate frequency signals through the first FPGA and the second FPGA.

[0172] Optionally, the processor 880 is further configured to divide the second preset number of intermediate frequency signals by using the first FPGA and the second FPGA, perform signal detection by using a fast Fourier transform FFT to obtain a signal detection result, select a target channel according to the signal detection result, and change a center frequency of the channel board to correspond to the target channel.

[0173] The RF circuit 810 is specifically configured to receive, through the target channel, service data transmitted according to the ACK signal.

[0174] Optionally, the RF circuit 810 is specifically configured to receive, through a first preset number of channels, radio frequency signals corresponding to a first frequency point transmitted at least twice by using a 4 times oversampling algorithm.

[0175] The RF circuit 810 is configured to receive service data sent according to the ACK signal by using an 8 times oversampling algorithm.

[0176] Optionally, the second preset number of channel frequencies is 50 byte / min or 11 byte / min.

[0177] Optionally, the terminal device comprises a channel board, a service board and a main control board.

[0178] The channel board, the service board and the main control board are connected through a serial port.

[0179] In an embodiment of the present application, the RF circuit 810 is configured to send a radio frequency signal corresponding to a first frequency point at least twice, the radio frequency signal corresponding to the first frequency point is used for screening a radio frequency signal, receive an ACK signal, and send service data according to the ACK signal.

[0180] Optionally, the first frequency point is selected according to empirical data, and the empirical data comprises at least one of historical spectrum data, empirical available frequency bands and geographical positions.

[0181] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product comprises one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. The computer instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) mode. The computer readable storage medium can be any available medium that can be stored by the computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available media can be magnetic media (for example, floppy disk, hard disk, magnetic tape), optical media (for example, DVD), or semiconductor media (for example, solid state disk (SSD)) and the like.

[0182] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0183] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic, and the division of the units is merely a logical function division, and there can be another division manner in actual implementation, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or in other forms.

[0184] The units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, that is, can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments.

[0185] In addition, each functional unit in the embodiments of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware, or in the form of software functional units.

[0186] When the integrated unit is realized in the form of software functional units and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on such an understanding, the technical solutions of the present application essentially or the part that makes a contribution to the prior art, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0187] The above-described embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A frequency selection method based on medium-long wave communication, characterized in that, The method is applied to a terminal device, the terminal device comprising a service board, the service board comprising a first FPGA and a second FPGA, comprising: Receiving radio frequency signals corresponding to a first frequency point sent at least twice through a first preset number of channels, the number of the first frequency points being 66 or 64, each frequency point corresponding to a channel; From the radio frequency signals corresponding to the first preset number of frequency points, screening out radio frequency signals corresponding to a second preset number of frequency points, the second preset number being less than the first preset number, the second preset number of frequency points being the top-ranked frequency points screened out according to the measured spectrum and historical experience; Dividing the radio frequency signals corresponding to the second preset number of frequency points by the first FPGA and the second FPGA, and performing signal detection by using fast Fourier transform (FFT) to obtain a signal detection result; According to the signal detection result, selecting a target channel, the frequency point corresponding to the target channel being the best frequency point in the second preset number of frequency points; Changing the center frequency of the channel board to correspond to the target channel; Feeding back an acknowledgement (ACK) signal through the target channel; Receiving service data sent according to the ACK signal through the target channel.

2. The method of claim 1, wherein, The terminal device further comprises a channel board, one end of the first FPGA being connected to an analog-to-digital converter (ADC) and the other end being connected to a digital-to-analog converter (DAC), the pin of the second FPGA being set as high resistance, the input and output pins of the first FPGA and the second FPGA being consistent; The method further comprises: Processing the radio frequency signals corresponding to the first preset number of frequency points by using the first ADC through the channel board to obtain intermediate frequency signals corresponding to the first preset number of frequency points; Transmitting the first preset number of intermediate frequency signals to the second FPGA through the first FPGA; From the intermediate frequency signals corresponding to the first preset number of frequency points, screening out intermediate frequency signals corresponding to a second preset number of frequency points through the first FPGA and the second FPGA.

3. The method according to claim 1 or 2, characterized in that, The method further comprises: Receiving the radio frequency signals corresponding to the first frequency point sent at least twice through the first preset number of channels by using a 4-fold oversampling algorithm; The method further comprises: Receiving the service data sent according to the ACK signal by using an 8-fold oversampling algorithm.

4. The method according to claim 1 or 2, characterized in that, The channel frequency of the second preset number is 50 byte / min or 11 byte / min.

5. The method of claim 2, wherein, The terminal device further comprises a main control board; the channel board, the service board and the main control board are connected through a serial port.

6. A frequency selection method based on medium-long wave communication, characterized in that, The method further comprises: The first frequency point corresponds to the radio frequency signal sent at least twice through the first preset number of channels, the first preset number of frequency points correspond to the radio frequency signal used to filter out the second preset number of frequency points corresponding to the radio frequency signal, the second preset number is less than the first preset number, and the second preset number of frequency points are selected according to the measured spectrum and historical experience. The top-ranked frequency points; the second preset number of frequency points correspond to the radio frequency signal used to divide by the first FPGA and the second FPGA, and the signal detection result is obtained by using fast Fourier transform (FFT) for signal detection; the signal detection result is used to select a target channel, the target channel corresponds to the best frequency point in the second preset number of frequency points, and the target channel is used to change the center frequency of the channel board corresponding to the target channel. The number of the first frequency points is 66 or 64, and each frequency point corresponds to a channel; The ACK signal is received through the target channel; The service data is sent according to the ACK signal through the target channel.

7. The method of claim 6, wherein, The first frequency point is selected according to experience data, and the experience data includes at least one of historical spectrum data, experience available frequency band, and geographical position.

8. A terminal device, comprising: The terminal device includes a service board, the service board includes a first FPGA and a second FPGA, and includes: The transceiver module is used for receiving the first frequency point corresponding to the radio frequency signal sent at least twice through the first preset number of channels, and the number of the first frequency points is 66 or 64, and each frequency point corresponds to a channel; The processing module is used for filtering out the second preset number of frequency points corresponding to the radio frequency signal from the first preset number of frequency points corresponding to the radio frequency signal, the second preset number is less than the first preset number, and the second preset number of frequency points are selected according to the measured spectrum and historical experience. The top-ranked frequency points; The processing module is also used for dividing the second preset number of frequency points corresponding to the radio frequency signal by the first FPGA and the second FPGA, using fast Fourier transform (FFT) for signal detection, and obtaining a signal detection result; according to the signal detection result, a target channel is selected, the target channel corresponds to the best frequency point in the second preset number of frequency points; change the center frequency of the channel board corresponding to the target channel; The transceiver module is also used for feeding back an ACK signal through the target channel; and receiving service data sent according to the ACK signal through the target channel.

9. A terminal device, comprising: includes: The transceiver module is used for sending the radio frequency signals corresponding to the first frequency points at least twice through the first preset number of channels, the radio frequency signals corresponding to the first preset number of frequency points are used for screening out the radio frequency signals corresponding to the second preset number of frequency points, the second preset number is smaller than the first preset number, the second preset number of frequency points are the top frequency points screened out according to the measured spectrum and historical experience, the radio frequency signals corresponding to the second preset number of frequency points are used for being divided by the first FPGA and the second FPGA, signal detection is carried out by using fast Fourier transform (FFT), and a signal detection result is obtained; the signal detection result is used for selecting a target channel, a frequency point corresponding to the target channel is the best frequency point in the second preset number of frequency points, the target channel is used for changing the center frequency of the channel board corresponding to the target channel, the number of the first frequency points is 66 or 64, each frequency point corresponds to a channel, the number of the first frequency points is 66 or 64, an ACK (acknowledgement) signal is received through the target channel, and service data is sent according to the ACK signal through the target channel.

10. A terminal device, comprising: Comprise: a memory storing executable program codes; a processor and a transceiver coupled with the memory; the processor invokes the executable program codes stored in the memory, so that the processor and the transceiver correspondingly execute the method as claimed in any one of claims 1-5, or 6 or 7.

11. A computer readable storage medium comprising instructions which, when executed on a processor, cause the processor to perform the method as claimed in any one of claims 1-5, or 6 or 7.

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