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M-PSK cooperative trellis codes for coordinate interleaved coded cooperation

M-PSK cooperative trellis codes are proposed for two-user coordinate interleaved coded cooperation operating over quasistatic Rayleigh fading channels. The coding approach properly combines cooperative and modulation diversity techniques to take their full advantage. Two selective cooperation schemes are considered related to whether users know the cooperation status or not. Upper bounds on the pairwise error probability of the considered schemes are derived for each cooperation case which lead to new code design criteria. Based on these criteria, 4-, 8-, 16-state QPSK and 8-, 16-state 8PSK cooperative trellis codes are obtained by means of exhaustive computer search. The error performance evaluation of the new codes by computer simulations shows that they outperform the corresponding best space-time codes used in cooperation with coordinate interleaving.

Coordinate Interleaved Coded Cooperation

In this paper, a two-user cooperative diversity scheme is proposed where coded cooperation and modulation diversity techniques are properly combined to take their full advantage. Users perform selective cooperation in transmission according to the correct estimation of symbols from their partners. Pairwise error probability analysis is performed for all cooperation cases and a tight upper bound on the bit error probability is obtained for rate compatible punctured convolutional codes and QPSK modulation. Numerical results show that the proposed system outperforms the coded cooperation technique given in by achieving two times more diversity.

Bandwidth-efficient code design for coordinate interleaved coded cooperation

A two-user coordinate interleaved coded cooperation scheme is proposed for quasi-static Rayleigh fading channels, where cooperative and modulation diversity techniques are properly combined to take their full advantage. Two selective cooperation schemes are considered related to whether users know the cooperation case or not. Pairwise error probability (PEP) analysis is performed for all cooperation cases and code design criteria are derived from the PEP upper bounds. Bandwidth-efficient 4-, 8- and 16-state rate 2/4 cooperative quadrature phase shift keying (QPSK) trellis codes are obtained based on these criteria by means of exhaustive computer search. The error performances of the new codes evaluated by computer simulations show their superiority compared to the corresponding best space-time codes used in cooperation with coordinate interleaving. The simulation results are supported by an upper bound on the bit error probability developed using union bounding technique.

Optimal step-size LMS equalizer algorithm

In this paper, an optimal step-size finding algorithm for LMS is presented. The algorithm runs iteratively and convergence to the equalizer coefficients by finding the optimal step-size which minimizes the steady-state error rate at each iteration. No initialization for the step-size value is required. Efficiency of the proposed algorithm is shown by making a performance comparison between some of the other LMS based algorithms and optimal step-size LMS algorithm.

A coordinate interleaved user cooperation scheme for distributed Alamouti space-time block code

A new coordinate interleaved user cooperation scheme for distributed Alamouti space-time block code (DSTBC) is presented. When coordinate interleaved symbols are transmitted using DSTBC, a diversity order of four is reached at the destination for perfect cooperation (PC) of two users. A selective cooperation (SC) approach is proposed to prevent detrimental effect of the interuser channel. Error performance of the proposed coordinate interleaved DSTBC (CI-DSTBC) for PC and SC in noisy interuser channel is evaluated by computer simulations for QPSK modulation and its superiority compared to the corresponding counterparts given in the literature is brought out.

Improving diversity order with coordinate interleaving for distributed space-time block codes

In this paper, improving diversity order at the destination is aimed when coordinate interleaved symbols are transmitted using distributed Alamoutis space-time block code. When users perfectly cooperate, diversity order can be doubled with coordinate interleaving. Error performance of the proposed system is evaluated by computer simulations for QPSK modulation and its superiority compared to the equivalent system without coordinate interleaving is demonstrated.

Code design for cooperative diversity with coordinate interleaving

In this paper, code design criteria for coded cooperation systems with coordinate interleaving are derived from analytically obtained upper bounds on pairwise error probabilities. 4- and 8-state optimum trellis codes are designed and their error performances are evaluated by computer simulations which show their superiority compared to their counterparts given in the literature.

Code design for coordinate interleaved coded cooperation

In this paper, code design criteria for coded cooperation systems with coordinate interleaving are derived from pairwise error probability upper bounds. Optimum 4, 8 and 16-state trellis codes are designed by means of exhaustive computer search. The error performances of the new codes evaluated by the computer simulations show their superiority compared to the corresponding best space-time codes used in cooperation with coordinate interleaving.

Cooperative Diversity with Coordinate Interleaving

In this paper, a two-user cooperative diversity scheme is proposed where the coded cooperation is performed with coordinate interleaving suitably to rate compatible punctured coding (RCPC) technique. Users perform selective cooperation in transmission, according to the correctness of the estimated symbols from their partners. Error performance of the proposed system is evaluated by computer simulations for QPSK modulation and its superiority compared to the corresponding reference systems is brought out.