Iterative interference cancellation and channel estimation in multibeam satellite systems

Abstract

SUMMARYThis paper deals with the use of non-linear multiuser detection techniques to mitigate co-channel interference on the reverse link of multibeam satellite systems. These techniques allow more capacity efficient frequency reuse strategies than classical ones, as they make possible to cope with lower C=I: The considered system takes as a starting point the DVB-RCS standard, with the use of convolutional coding, and the use of the Ka-band.We propose different iterative interference cancellation schemes, which operate at the beamformer outputs, and which use information from decoders. The proposed receivers assume an initial single-user synchronization step: frame synchronization and timing recovery, and then perform channel estimation: beamformer coefficients; signal carrier phases and signal amplitudes.In a first step, these receivers are evaluated by simulation in terms of bit error rate and of channel estimation error on two interference configurations. For one of these receivers, sensitivity to imperfect timing recovery and to low-frequency offsets from user terminals is evaluated.In a second step, since the receiver performances highly depend on the interference configuration, we propose an approach to evaluate performances on a multibeam coverage (by taking into account the variability of interference configurations on the coverage). This method is used to compare different receivers on an example based on a coverage designed on a digital focal array feed reflector antenna.

Performance, cost analysis, and ground segment design of ultra high throughput multi‐spot beam satellite networks applying different capacity enhancing techniques

“…Millerioux et al . investigate the effect of non‐linear multi‐user detection technique for reducing the effect of co‐channel interference in the return link of satellite system . In particular, they consider an iterative parallel interference cancellation technique rather than a centralized multi‐user detector followed by a set of single‐user decoders.…”

Multiuser detection in the presence of strong phase noise for DVB-RCS systems

“…In [3], the authors use modified branch metrics for the Viterbi decoder instead of predistortion. However, the work done on multi-user techniques like iterative ACI/CCI cancellation for satellite communications [4][5][6][7], or multi-user (burst) synchronization [8,9] assume a linearized on-board HPA, or totally ignore the HPA effect. Moreover, when dealing with multiple interfering signals the difference in phase offsets, carrier frequency offsets, and power levels of the interfering signals at the satellite transponder input results in varying satellite behaviour.…”

Coarse recovery of carrier frequency and symbol timing in multibeam satellite channels

“…Of course, the performance of such a solution is significantly affected by interference effects, which have to be treated by an appropriately selected interference mitigation technique. Most prominent examples in this context are linear as well as nonlinear precoding algorithms and multiuser detection (MUD) schemes, both of them excellently summarized and discussed in several chapters of Chatzinotas et al, but the interested reader is also referred to Devillers et al, Christopoulos et al, Zheng et al, Moher, Millerioux et al, Arnau et al, and Christopoulos et al, respectively.…”