Frame synchronization for pulsed jammed satellite telecommand links. (21st April 2019)

• Record Type: Journal Article
• Authors: Noels, Nele; Moeneclaey, Marc
• Is Part Of: International journal of satellite communications and networking. Volume 38:Number 1(2020)
• Page Start: 16
• Page End: 30
• Publication Date: 2019-04-21
• Subjects: frame synchronization -- pulsed jamming -- satellite telecommand system; Artificial satellites in telecommunication -- Periodicals; Digital communications -- Periodicals; 621.3825
• DOI: 10.1002/sat.1305
• Languages: English
• ISSNs: 1542-0973

Abstract

Summary: A new issue of the satellite telecommand synchronization and channel coding sublayer protocol includes LDPC‐coded communication link transmission units (CLTUs) that contain a 64‐bit start sequence. The novel data structures allow operation at lower signal‐to‐noise ratios than before and offer improved protection against jamming attacks. This paper considers the corresponding CLTU frame synchronization process. We derive practical algorithms to locate the start sequence in the presence of high noise levels and pulsed jamming. The different algorithms are compared in terms of implementation complexity and performance under various jamming conditions. It is shown that among the considered frame synchronizers, those involving a full search over the entire observation window provide the desired accuracy, ie, they guarantee a frame synchronization error probability that is significantly smaller than the codeword error rate, for codeword error rates near a target value of 10 −4 . Among these synchronizers, the full‐search hard‐decision–directed correlation‐based algorithm has the lowest complexity. Abstract : In view of the recent update of the standard for satellite telecommand systems, we study the corresponding frame synchronization in the presence of high noise levels and pulsed jamming. Potential algorithms are compared in complexity and performance. We identify those providing a frame synchronization error probability that is significantly smaller than the codeword error rate (CER), for CERs near a target value of 10–4, under all relevant channel conditions. Among these synchronizers, the one with the lowest complexity is selected.