"Turbo DPSK" using soft multiple-symbol differential sphere decoding

2011 IEEE International Conference on Communications (ICC)

2011

Abstract-This paper presents a multiple-symbol differential spatial division multiple access (MS-DSDMA) system conceived for lowcomplexity and high-bandwidth-efficiency applications operating in timevarying fading channels, where no channel estimation is required. A low-complexity adaptive multiple-symbol differential interference suppression (MS-DIS) scheme is proposed, which is based on the maximum signal-to-interference-plus-noise ratio (MSINR) criterion and facilitates the implementation of the powerful multiple-symbol differential sphere detection (MSDSD). Then, a practical three-stage turbo DIS receiver design framework is proposed for the MS-DSDMA system, which is constituted by concatenating the adaptive DIS filter bank, the MSDSD and the channel decoder. Both the EXtrinsic Information Transfer (EXIT) chart analysis and the Monte-Carlo-based simulation results show that the proposed three-stage turbo DIS scheme is capable of achieving a substantially enhanced performance in comparison to the conventional linear minimum mean-squared error (LMMSE) based adaptive receiver. Furthermore, for the sake of significantly reducing the iterative detection complexity, two complexity reduction techniques are devised, namely the a priori-LLR-threshold (ALT) and the adaptive-window-duration (AWD) aided MSDSD schemes.

Section: B Multiple-symbol Differential Sphere Detectionmentioning

confidence: 99%

Section: B Multiple-symbol Differential Sphere Detectionmentioning

confidence: 99%

Multiple-Symbol Detection Aided Differential Spatial Division Multiple Access

Wang

2011 IEEE International Conference on Communications (ICC)

2011

“…The hard-output MSDSD designed for the DSTM of [5] should be modified in order to be used in turbo detection. Similarly to the soft-output DPSK MSDSD of [6], the Sphere Decoder (SD) aims to find the optimum ( ) blocks that leads to the minimum Euclidean distance, which is formulated as (6) where denotes the decoding sphere radius, which is minimized by the SD. The coefficient in (6) represents the predictor coefficients hosted by the corresponding elements in the lower triangular matrix in [6, eq.…”

Section: Soft-decision Aided Msdsd Decoder Designed For Dstmmentioning

confidence: 99%

“…The price paid is that the complexity imposed increases exponentially with . To mitigate the complexity, Multiple-Symbol Differential Sphere Decoding (MSDSD) was proposed for Differential Space-Time Modulation (DSTM) including DSTBCs as well as DLDCs in [5] a further advance, a soft-output MSDSD designed for DPSK was proposed in [6] for the sake of turbo detection. A novel MSDSD aided cooperative Amplify-and-Forward (AF) design was proposed in [7], where a low BER can only be achieved in the high-SNR region.…”

Section: Introductionmentioning

confidence: 99%

Near-Capacity Irregular Convolutional Coded Cooperative Differential Linear Dispersion Codes Using Multiple-Symbol Differential Detection

IEEE Signal Process. Lett.

2011

Abstract-We propose a novel near-capacity Multiple-Symbol Differential Decoding (MSDD) aided cooperative Differential Linear Dispersion Code (DLDC) scheme, which exhibits a high grade of system design flexibility in terms of the choice of activated relays and the DLDC's rate allocation. More specifically, the system has the freedom to activate a range of DLDCs depending on both the number of relays available in the network, as well as on their position, throughput and complexity considerations.

“…between the same subcarrier of two consecutive OFDM symbols. Due to space limitation, we refer the interested reader to [22] for more information on turbo-style SISO-MSDSD detection, whilst details on the URC and RSC decoders can be found in [14] [23].…”

Section: Further Enhancements Across the Protocol Stackmentioning

confidence: 99%

On-Demand Decode and Forward Cooperative MAC for VoIP in Wireless Mesh Networks

Cheung

2011 IEEE Vehicular Technology Conference (VTC Fall)

2011

Abstract-1 The employment of wireless mesh networking in reallife scenarios has attracted substantial research interest in recent years and in this context VoIP has become a ubiquitous application. However, it has been demonstrated that VoIP transmissions over a multihop network may still remain inadequate in terms of their high packet-loss ratio and network-induced delays. To alleviate these limitations, we propose a novel distributed MAC-layer cooperation protocol, which is based on the decode-and-forward regime, whilst relying on the lowest possible control packet overhead. Furthermore, we employ several improvements across the protocol stack, including an improved PHY-layer, based on three-stage turbo-style differential detection, packet aggregation in the MAC-layer, as well as on adjusting the retransmission limit of each packet in order to reduce the delay imposed when employing cooperation. We characterize our improved system in a Wireless Mesh Network (WMN) scenario using the OMNeT++ network simulator and compare it to an 802.11g-based benchmarker. As a benefit of these techniques, we have observed up to 10-fold reduction in the energy consumption per bit, despite increasing the number of simultaneous calls supported by up to 9, when the number of hops between the sources and destination is 6.