High-efficiency implementation of multi-channel spread spectrum scrambling and shaping filtering system on the satellite

Abstract

A system for realizing multi-channel spread spectrum scrambling and shaping filtering with high efficiency on the star is implemented on a single-chip FPGA, including a system controller, n-way processing modules, two combiners and two shaping filters; the system The controller contains a RAM for pre-storing various initial values. The initial values ​​include the number of the spreading factor of the orthogonal variable spreading factor code and the sequence number of the code word of the orthogonal variable spreading factor code used by the system and The initial phase of the complex scrambling code; each of the n-way processing modules includes a sub-control unit, a RAM storing data to be processed, a serial-to-parallel converter, a spreading code generator, a complex scrambling code generator, a spreading modulator and Complex scrambling code modulator; the present invention overcomes the deficiencies of the prior art, and can efficiently realize multi-channel channel spreading, scrambling and shaping filtering processing under the condition of satisfying the size and quantity restrictions of the FPGA chip selected by the satellite.

Description

technical field [0001] The invention relates to the fields of multi-channel spread spectrum, scrambling and shaping filter processing in a communication system, in particular to a method for realizing high-efficiency FPGA implementation on a satellite system. Background technique [0002] In communication systems, spread spectrum processing is to multiply a high-speed digital sequence with a digital signal, convert a data symbol into a series of chips, increase the rate of digital symbols, increase the signal bandwidth, and improve the anti-noise ability of the signal. Scrambling processing is to multiply a pseudo-random sequence with the sequence after spreading to encrypt and scramble the signal, and can be used to distinguish users, cells and channels. For baseband digital signals, modulation and transmission can only be carried out after waveform transformation through shaping filtering. It can be seen that spreading, scrambling, and shaping filtering are all important ...

AI Technical Summary

Problems solved by technology

However, in the implementation process, when it is necessary to deal with the multi-channel communication system, it takes up a lot of FPGA resources, so it is necessary to use a larger-scale FPGA chip to implement

[0004] Due to the special working environment of the satellite, the use of FPGA in space is vulnerable to the influence of various cosmic ray radiation, which will cause wrong flipping of the working timing of FPGA

FPGAs with more logic resources are more likely to be affected by radiation, and errors are more likely to occur during work. Therefore, in order to ensure the reliability of satellite in-orbit work, FPGAs with too many logic resources should not be used on satellites, nor should more FPGA chips be used.

However, in practical applications, the processing power of the satellite cannot be reduced because of the use of a small-scale FPGA.

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