D8PSK coherent demodulation method and system

Abstract

The invention discloses a D8PSK coherent demodulation method and system, and the method comprises the steps: enabling a band-pass filter to receive a sampling modulation signal sent by AD sampling, and carrying out the band-pass filtering; processing the two paths of output signals of the band-pass filter to obtain baseband signals of an in-phase path and an orthogonal path; processing the baseband signals of the in-phase path and the orthogonal path to obtain two orthogonal paths of values of the optimal judgment sampling point of each symbol; feeding the two orthogonal paths of values of theoptimal judgment sampling point into a differential demodulation unit, a phase-locked loop unit, a frequency offset estimation unit and a frame synchronization unit at the same time; sending the differential decomposition modulation value is sent to a parallel-serial conversion unit, converting parallel input is converted into serial output, and acquiring a final demodulation sequence is obtained. A ; according to the method, a Gardner-based multi-level code element synchronization algorithm and a D8PSK difference decomposition modulation feedback-based phase synchronization algorithm are provided, so that the calculated amount is reduced to a great extent, and the engineering practice is facilitated.

Description

technical field [0001] The present invention relates to the field of ground-air communication, in particular to a D8PSK coherent demodulation method and system. Background technique [0002] Civil aviation ground-air communication and the transition from analog voice communication to data link communication gradually. The ground-air data link will gradually play an important role in civil aviation ground-air communication. Aircraft Communications Addressing and Reporting System (ACARS), as the current main ground-to-air data link communication method, has the characteristics of low speed, character-oriented transmission and poor confidentiality. ACARS cannot meet the application requirements of large capacity, high speed, and low latency in the current space. The Aeronautical Telecommunications Network (ATN) will replace ACARS as the next-generation aviation communication network. Compared with the ACARS data link, the ground-to-air data link it supports, VDL M2, has the a...

AI Technical Summary

Problems solved by technology

[0004] The invention provides a D8PSK coherent demodulation method and system, which solves the technical problems that the existing D8PSK coherent demodulation method needs to consume a large amount of storage resources and computing units, and is difficult in engineering practice. This method proposes a Gardner-based multi-level Symbol synchronization and phase synchronization algorithm based on D8PSK differential demodulation feedback greatly reduce the amount of calculation, which is beneficial to engineering practice

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