CN-116953737-B - Fpga-based gps signal generation method

CN116953737BCN 116953737 BCN116953737 BCN 116953737BCN-116953737-B

Abstract

The invention provides a gps signal generation method based on Fpga, and relates to the technical field of wireless communication. The generation method specifically comprises the following steps of S1, determining signal requirements, carrying out a prefabricated signal rule template comprising at least one variable rule according to the required signal direction and purpose, S2, generating at fixed points, and determining signal loading values of signal generation frequency, waveform and amplitude. The method can be used for transmitting various different gps signals, can realize signal source combination transmission without additional plate making, can realize signals of various types on any required frequency band, can change the combined mode in real time by inputting control parameters according to the needs, has simple structure, flexible control, time and cost saving, is also beneficial to the improvement of the signal source, has good adaptability and expandability, can quickly realize the gps signal simulation of various systems by only carrying out adaptive modification and adjusting the variable parameters of the prefabricated signal template.

Inventors

WANG JUN
ZHOU YUNFEI

Assignees

福州大学
福建金石电子有限公司

Dates

Publication Date: 20260508
Application Date: 20230714

Claims (7)

1. The gps signal generation method based on Fpga is characterized by comprising the following steps of: S1, determining signal requirements: Performing a prefabricated signal rule template comprising at least one variable rule according to the required gps signal direction and purpose; s2, fixed point generation: determining signal loading values of signal generation frequency, waveform and amplitude, and generating a directional signal based on Fpga internal port resource ends; s3, signal processing: The decimal integration is carried out by utilizing 12-bit binary system, the frequency synthesizer is utilized for receiving the directional signal generated based on Fpga resource ends and completing character integration, and meanwhile, a cutting switch is utilized for cutting and outputting the directional signal; s4, directional conversion: the directional output gps signals which finish the decimal integration, character integration and cutting output processing in the S3 are subjected to frequency conversion by a frequency conversion module; s5, signal sending: And transmitting the final variable-frequency directional output signal to a transmitter, and generating and transmitting a final signal after the virtual and real calculation of the final signal is completed by utilizing a multiplication operation and trigonometric function operation module.
2. The gps signal generating method based on Fpga as set forth in claim 1, wherein the variable rule included in the prefabricated signal rule module in S1 includes three variables of signal type, frequency and amplitude.
3. The method for generating the gps signal based on Fpga of claim 1, wherein the Fpga internal port resource end in S2 is an FPGA internal dual-port RAM resource, directional signal parameters are written through a port 1, a timing sequence is generated through a port 2 according to signals, and a directional signal, a preamble signal, a signal frequency control word and a control signal of an amplitude control word are output, wherein the timing sequence between the preamble signal and the directional signal is fixed and is output before the directional signal.
4. The gps signal generating method based on Fpga, as set forth in claim 1, wherein the 12-bit binary decimal integration in S3 performs decimal expansion by using 12-bit binary multiplication, and the decimal expansion is represented by an integer, and the frequency synthesizer generates the corresponding connection wave signal according to the frequency control word and the amplitude control word output based on Fpga.
5. The gps signal generating method based on Fpga as set forth in claim 1, wherein the frequency conversion module in S4 includes two generating clocks and an intermediate frequency signal frequency conversion, and wherein the two generating clocks are designed in parallel.
6. The gps signal generating method based on Fpga as set forth in claim 1, wherein the frequency conversion module in S4 includes a Fpga frequency conversion unit and a signal frequency conversion unit based on an initial pre-fabricated signal rule template, and wherein the signal frequency conversion unit is connected in series based on a Fpga frequency conversion unit and based on the initial pre-fabricated signal rule template.
7. The gps signal generating method according to claim 1, wherein the gps signal generating system comprises a comprehensive control unit and a Fpga unit, the comprehensive control unit is connected with a signal synthesizer, the signal synthesizer is connected with a frequency conversion module, the frequency conversion module is connected with a signal generator, the signal generator is connected with a signal transmitter, and the comprehensive control unit is electrically connected with the Fpga unit.

Description

Fpga-based gps signal generation method Technical Field The invention relates to the technical field of wireless communication, in particular to a gps signal generation method based on Fpga. Background With the implementation of GPS modernization, more and more GPS satellites use the application of adding civil signals to L2 carrier frequency, so that GPS civil users can also use L1 and L2 dual frequencies to correct ionosphere propagation errors, and the signals adopt special civil medium-length codes (CM codes) and civil long codes (CL codes) for time division multiplexing, and are more suitable for being applied in weak environments such as indoor environments, boulevards, tunnels and the like. FPGA is a product of further development based on PAL, GAL, CPLD and other Programmable devices, and is presented as a semi-custom circuit in the Field of Application Specific Integrated Circuits (ASIC), and is known as Field-Programmable GATE ARRAY, i.e., field-Programmable gate array. The application fields of the common FPGA include algorithm acceleration, video image processing, communication field, medical field, security field and the like. Since the FPGA was created in 1984 by Xilinx, the programmable logic device has obvious advantages in terms of performance, time to market, cost, stability and long-term maintenance, and has a place in the fields of communication, medical treatment, security and the like. However, as shown in the prior patent (publication number: CN 110933003A) and the prior patent (publication number: CN 109857014A) which are related to the generation method of the DMRS signal based on the FPGA, the prior patent (publication number: CN 113960577A) which is related to the generation method of the PWM signal based on the FPGA and the prior patent (publication number: CN 113960577A) which is related to the generation method of the active sonar signal based on the FPGA, the signals generated by the FPGA are various, but a generation method applied to the generation of the GPS signal and the conversion frequency conversion is lacked. Disclosure of Invention (One) solving the technical problems Aiming at the defects of the prior art, the invention provides a gps signal generation method based on Fpga, which solves the problem that the signal generation based on the FPGA lacks a generation method for gps signal application and conversion frequency conversion in the prior art. (II) technical scheme In order to achieve the purpose, the invention is realized by the following technical scheme that the gps signal generating method based on Fpga specifically comprises the following steps: s1, determining signal requirements Performing a pre-made signal rule template comprising at least one variable rule according to the required signal direction and purpose; s2, fixed point generation Determining signal loading values of signal generation frequency, waveform and amplitude, and generating a directional signal based on Fpga internal port resource ends; s3, signal processing The decimal integration is carried out by utilizing 12-bit binary system, the frequency synthesizer is utilized for receiving the directional signal generated based on Fpga resource ends and completing character integration, and meanwhile, a cutting switch is utilized for cutting and outputting the directional signal; s4, directional conversion The directional output signals which finish the decimal integration, character integration and cutting output processing in the S3 are subjected to frequency conversion by a frequency conversion module; s5, signal sending And generating the final variable-frequency directional output signal to a transmitter, and generating a final signal after the virtual and real calculation of the final signal is completed by utilizing a multiplication operation and trigonometric function operation module. Preferably, the variable rule included in the prefabricated signal rule module in S1 includes three variables of signal type, frequency and amplitude. Preferably, the internal port resource based Fpga in S2 is a dual-port RAM resource based on FPGA, the directional signal parameter is written through the port 1, and the directional signal, the preamble signal, the control signal of the signal frequency control word and the amplitude control word are output according to the signal generation time sequence through the port 2, wherein the time sequence between the preamble signal and the directional signal is fixed and is output before the directional signal. Preferably, the 12-bit binary decimal integration in S3 performs decimal expansion by using 12-bit binary multiplication, and is expressed as an integer, and the frequency synthesizer generates a corresponding connection wave signal according to the frequency control word and the amplitude control word output based on Fpga. Preferably, the frequency conversion module in S4 includes two generating clocks and frequency conversion of the intermediate frequ