Short wave speed change communication system and multipath estimation and separation method used by same

Abstract

The invention relates to a short wave speed change communication system and a multipath estimation and separation method used by the short wave speed change communication system. The short wave speed change communication system comprises a communication terminal A and a communication terminal B which communicate through a short wave channel, wherein the communication terminal A comprises a modulator A and a demodulator A, and the communication terminal B comprises a modulator B, a demodulator B and a multipath estimation and separation module; the multipath estimation and separation module is connected with the modulator B and used for calculating a code element period value required in the multipath separation, sending the code element period value into the modulator B, and finally transmitting the code element period value to the communication terminal A through the short wave channel; and the demodulator B comprises an analog-digital converter, the analog-digital converter is connected with a shock filter, the shock filter is connected with a detection judgment module, and the detection judgment module is connected with a bit synchronization module which is used for outputting an information sequence. According to the short wave speed change communication system and a multipath estimation and separation method used by the short wave speed change communication system, the multipath interference can be separated without complex channel equalization, the transmission efficiency and the demodulation performance are improved, and the cost and the complexity for realizing communication system hardware are reduced.

Description

technical field [0001] The present invention relates to the high-speed data transmission of the digital communication system on the short-wave multipath fading channel, especially adopting a kind of extended binary phase-shift keying modulation and a special filter to quickly estimate the short-wave channel parameters and efficiently demodulate the short-wave communication data, It belongs to the technical field of communication signal processing. Background technique [0002] 1. Short wave communication [0003] Shortwave communication is radio communication using electromagnetic waves with a wavelength of 100-10m (frequency 3-30MHz). The transmitted radio waves must be reflected by the ionosphere to reach the receiving equipment, which is the main means of long-distance communication. [0004] 1) Obvious advantages [0005] In mountainous areas, Gobi, oceans and other areas, ultra-short wave coverage is not available, and short-wave and satellites are mainly relied on, ...

AI Technical Summary

Problems solved by technology

Moreover, short-wave is the only means of long-distance communication that is not restricted by network hubs and active relays. In the event of war or disaster, various communication networks may be damaged, and satellites may also be attacked. The indestructibility and autonomous communication of these communication methods Capabilities unmatched by shortwave communications

[0006] 2) Serious disadvantages

[0038] For asymmetric modulation where the difference between "0" and "1" waveforms is small, the classical matched filter and correlation detection methods for symmetrically modulated waveforms are no longer optimal

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