Walid Abediseid

Lattice sequential decoder for coded MIMO channel: Performance and complexity analysis

In this paper, the performance limits and computational complexity of lattice sequential decoder for coded MIMO channel are analyzed. It is shown that using nested lattice codes, the optimal diversity-multiplexing tradeoff of the channel can be achieved in the presence of such very low complexity decoder. We show that the computational complexity distribution, at high signal-to-noise ratio, is dominated by the outage probability.

A linearizing approach to code design for generalized MSK with four symbol pulse duration

Quadruple repetition code exhibits unique properties when combined with precoded generalized minimum-shift keying signals of up to four symbol period pulse duration. It is shown that using two stages of channel encoding, the last being a quadruple repetition code, the code design for such modulation schemes simplifies. Also, it is shown that the nonlinear continuous-phase frequency-shift keying modulator can be replaced by a simple linear I-Q modulator to generate the same coded signals. The detection problem for the recovery of the symbols sequence from the decision variables is shown to be one corresponding to memoryless modulation, avoiding the use of maximum likelihood sequence detection.

Time-Out Lattice Sequential Decoding for the MIMO ARQ Channel

The optimal diversity-multiplexing-delay tradeoff for the multi- input multi-output (MIMO) automatic repeat request (ARQ) channel can be achieved using an incremental redundancy lattice space- time codes. The optimal tradeoff has been shown in [1] to be achieved using a list lattice decoder for joint detection and decoding. However, such decoder suffers from high computational complexity for low-to-moderate signal-to-noise ratios, especially for large signals dimension. In this paper, we would like to construct a more efficient decoder that is capable of achieving the optimal tradeoff with much lower complexity. We show, analytically and via simulation, that using a modified lattice sequential decoder for joint error detection and correction in the MIMO ARQ channel, the optimal tradeoff can be achieved with significant reduction in decoder complexity at a very small degradation in performance.

Lattice Sequential Decoding: Achievable Rates and Diversity-Multiplexing Tradeoff

In this paper, the performance limit of lattice sequential decoder for coded

New system design for serial-MSK based on Laurent decomposition

M\times N

A simplified approach to coding, modulation, and detection design for generalized MSK with two symbol period pulse duration

MIMO channel is analysed. We determine the rates achievable by lattice coding and sequential decoding applied to such channel. The diversity-multiplexing trade- off under lattice sequential decoding is derived as a function of its parameter---the bias term. Such parameter is critical for controlling the amount of computations required at the decoding stage. Achieving low decoding complexity requires increasing the value of the bias term. However, this is done at the expense of losing the optimal trade- off of the channel. We show how such decoder can bridge the gap between lattice decoder and low complexity decoders [e.g., minimum mean-square error successive interference cancellation (MMSE-SIC)]. We argue that, MMSE-SIC may achieve close to the maximum diversity gain of the channel

Lattice Sequential Decoding for LAST Coded MIMO Channels: Achievable Rate, DMT, and Complexity Analysis

MN

A linearizing approach to coding for generalized MSK

at very low multiplexing gain.

On the Average Complexity of Sphere Decoding in Lattice Space-Time Coded MIMO Channel

In this paper, a new approach to coding, modulation, and detection design for serial minimum-shift keying (MSK) modulation scheme is presented. The design of the new linear modulator is based on the Laurent decomposition of a well-known modified MSK scheme termed duobinary MSK. It is shown that a simple linear receiver can be designed to optimally detect the coded symbols. The detection problem for the recovery of the symbols sequence from the decision variable sequence is one corresponding to memoryless linear modulation. It is also demonstrated that the Euclidean distance between different signals is directly related to the Hamming distance between corresponding coded sequence. Therefore, optimum encoders (for a given rate and constraint length) that maximize the minimum Hamming distance can be applied.

Efficient Lattice Decoders for the Linear Gaussian Vector Channel: Performance & Complexity Analysis

Double repetition code exhibits unique properties when combined with precoded generalized minimum-shift keying signals of up to two symbol period pulse duration. It is shown that using two stages of channel encoding, the last being a double repetition code, the code design for such modulation scheme simplifies. Also, it is shown that the nonlinear continuous-phase frequency-shift keying modulator can be replaced by a simple linear I-Q modulator to generate the same coded signals. The detection problem for the recovery of the symbols sequence from the decision variables is shown to be one corresponding to memoryless modulation, avoiding the use of the maximum likelihood sequence detection.