RADIO PHYSICS AND RADIO ASTRONOMY

Subject and Purpose. The objective of Part 2 of the work is the development and experimental study of a multichannel correlator for creating a correlation-type transceiver based on software-defined radio (SDR) systems. The signal formation, reception, and decoding due to direct sequence spread spectrum (DSSS) technology are studied for organizing discreet transmission of digital information and reception of video images using software-defined radio systems.

Methods and Methodology. The algorithm software for the multichannel correlator is designed to integrate with a correlation-type receiver in a spread-spectrum communication system that uses direct sequence spread spectrum technology. This includes testing and hardware checks for software solutions related to data reception, conversion, processing, and mapping.

Results. An algorithm for generating and decoding signals of a sub-noise correlation communication system has been implemented, using the spreading signal method for data transmission with noise-like Gold-code-based signals. The basic software of the bladeRFx40 radio system has been modified. Namely, software modules for the correlation-type transceiver have been developed for coherent and incoherent reception using single-channel and multi-channel correlators. The main software solutions for data reception, conversion, processing, and mapping have been experimentally studied and tested.The functional capabilities of the software and hardware to incorporate with the system have been assessed and analyzed.

Conclusions. The research and development of digital communication channels through signal coding by the direct sequence spread spectrum method and with Gold codes have shown the technical feasibility of advanced compact devices for organizing interference-immune sub-noise multi-channel communication for data transmission in contemporary contexts.

Keywords: communication system; interference-immune communication; DSSS technology; Gold codes; multi-channel correlator; SDR receiver; digital stream

Manuscript submitted 09.02.2025

Radio phys. radio astron. 2025, 30(2): 109-119

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