Multisymbol with memory noncoherent detection of CPFSK

Multisymbol receiver is an effective method to demodulate noncoherent sequences. However it is necessary to correlate an important number of symbols in a noncoherent scheme to reach the performances carried out by optimal coherent Maximum a Posteriori (MAP) detectors such as BCJR. In this paper, we propose an advanced multisymbol receiver by adding some memory to the decision process. The advanced receiver, called here Multisymbol With Memory (MWM) takes into account the cumulative phase information unlike multisymbol algorithm and thus it can be seen as a truncated BCJR. An exact mathematical derivation is performed for this truncated BCJR. Then an implementation of the MWM detector applied to a continuous phase frequency shift keying modulation is presented. Finally an asymptotic analysis is carried out based on the achievable Symmetric Mutual Information rate. The proposed system exhibits good performances compared to classical multisymbol receivers at the expense of increased complexity and can approach the performances of a coherent receiver

Precoding for Non-coherent Detection of Continuous Phase Modulations

Non-coherent trellis based receiver (TBR) is an effective method to demodulate noncoherent continuous-phase modulated sequences. However it requires to increase the observation length to reach the performance of classical coherent TBRs. Furthermore it appears that both receivers offers different behaviours when considered in a bit-interleaved coded modulation (BICM) system using iterative decoding. Indeed, trellis based outer coding schemes performing well in coherent regime generate error floors in non-coherent regime. In this paper, we show that precoding of the continuous phase modulation (CPM) encoder can deal with the latter issue. The optimization of this non-coherent precoding relies on different objectives than the existing precoding methods introduced in the coherent case. The optimization relies on some asymptotic arguments enabling an efficient BICM scheme using iterative decoding. Using the proposed precoding approach enables to remove error floors in the non-coherent regime while enabling transparent use in the coherent case

Multisymbol With Memory Noncoherent Detection of CPFSK

International audienceMultisymbol receiver is an effective method to demodulate noncoherent sequences. However it is necessary to correlate an important number of symbols in a noncoherent scheme to reach the performances carried out by optimal coherent Maximum a Posteriori (MAP) detectors such as BCJR. In this paper, we propose an advanced multisymbol receiver by adding some memory to the decision process. The advanced receiver, called here Multisymbol With Memory (MWM) takes into account the cumulative phase information unlike multisymbol algorithm and thus it can be seen as a truncated BCJR. An exact mathematical derivation is performed for this truncated BCJR. Then an implementation of the MWM detector applied to a continuous phase frequency shift keying modulation is presented. Finally an asymptotic analysis is carried out based on the achievable Symmetric Mutual Information rate. The proposed system exhibits good performances compared to classical multisymbol receivers at the expense of increased complexity and can approach the performances of a coherent receiver

Détection non-cohérente souple par bloc ou à mémoire des CPM

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Multisymbol With Memory Noncoherent Detection of CPFSK

International audienceMultisymbol receiver is an effective method to demodulate noncoherent sequences. However it is necessary to correlate an important number of symbols in a noncoherent scheme to reach the performances carried out by optimal coherent Maximum a Posteriori (MAP) detectors such as BCJR. In this paper, we propose an advanced multisymbol receiver by adding some memory to the decision process. The advanced receiver, called here Multisymbol With Memory (MWM) takes into account the cumulative phase information unlike multisymbol algorithm and thus it can be seen as a truncated BCJR. An exact mathematical derivation is performed for this truncated BCJR. Then an implementation of the MWM detector applied to a continuous phase frequency shift keying modulation is presented. Finally an asymptotic analysis is carried out based on the achievable Symmetric Mutual Information rate. The proposed system exhibits good performances compared to classical multisymbol receivers at the expense of increased complexity and can approach the performances of a coherent receiver

Minimal state noncoherent symbol MAP detection of Continuous-Phase-Modulations

International audienceTrellis-based detector is an effective method to demodulate non-coherent continuous-phase modulated sequences. Most of them have been derived for the maximum likelihood sequence estimation setting, while only few contributions have been proposed for the maximum a posteriori (MAP) symbol detection, required when soft information is needed for iterative detection and decoding. In this letter, we derive a new symbol MAP non-coherent receiver with reduced state space representation compared with the existing extended state-space-based approaches. While having the same performance, it enables a lower complexity