Comparison of channel codes in presence of pulsed jammers in TT&amp;amp;C links

Moeneclaey

2019

Satell Commun Network

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.

Section: Introductionmentioning

confidence: 99%

Frame synchronization for pulsed jammed satellite telecommand links

Moeneclaey

2019

Satell Commun Network

“…On the other hand, the new issue of the CCSDS satellite TC synchronization and channel coding sublayer protocol, published in September 2017, has introduced a novel communication link transmission unit (CLTU) structure with advanced LDPC channel coding. It has been shown that, under perfect synchronization, these codes can offer an increased resilience against jamming. In practice, however, a system is never a priori synchronized, and the structures that are in place to perform synchronization are themselves susceptible to jamming attacks.…”

Section: Introductionmentioning

confidence: 99%

Towards improved satellite telecommand link availability

Sánchez

2018

Satell Commun Network

Summary Compliant with the Consultative Committee for Space Data Systems (CCSDS) set of protocols, we explore enhancing the availability service for space links. In particular, we consider specific improved defences against jamming attacks affecting symbol synchronization. More robust adaptive closed‐loop symbol synchronizers are designated with a view to the planned update of the CCSDS standard for the telecommand synchronization and channel coding sublayer of the data link layer. It is shown that adaptive schemes exploiting instantaneous jammer state information are recommended to counter destructive attacks that may harm the availability.

“…with Π (z) (x, y) the probability that x hard decision errors occur when z out of y observed bit intervals are jammed, defined in (3).…”

Section: B False Alarm Probabilitymentioning

confidence: 99%

“…To increase the resilience of satellite telecommand (TC) links against jamming, next generation TC systems are planning to adopt direct-sequence spread spectrum (DSSS) modulation with a very long pseudo-noise spreading code repetition period and a high spreading factor [1], along with advanced channel coding [2], [3].…”

Section: Introduction and State-of-the-artmentioning

confidence: 99%

“…For the next generation uplink CCSDS standard, more advanced channel codes are being put forward [4]. In [2], [3], the codeword error rate (CER) performances of the current BCH(63,56) and some of the proposed coding schemes are investigated under DSSS modulation in the presence of jamming, assuming perfect synchronization.…”

Section: Introduction and State-of-the-artmentioning

confidence: 99%

See 1 more Smart Citation

Performance of advanced telecommand frame synchronizer under pulsed jamming conditions

2017 IEEE International Conference on Communications (ICC)

Moeneclaey

2017

Abstract-This paper studies frame synchronization for use with the advanced communication link transmission unit format that was recently proposed for updating the telecommand synchronization and channel coding standard for space applications. With a view to improving the robustness against jamming, future satellite telecommand systems are planning to adopt directsequence spread spectrum modulation and advanced channel coding. Compared to the frame synchronization algorithm specified in the current Consultative Committee for Space Data Systems (CCSDS) recommendation, we consider a longer start sequence and relax the condition for declaring synchronization. We investigate the performance of this algorithm in the presence of jamming, and show that the frame synchronizer can be designed such that the overall system's robustness against pulsed jamming is limited by the robustness of the code rather than the synchronizer.