Cross‐layer design for MIMO systems over spatially correlated and keyhole Nakagami‐m fading channels

Abstract

Cross‐layer design is a generic designation for a set of efficient adaptive transmission schemes, across multiple layers of the protocol stack, that are aimed at enhancing the spectral efficiency and increasing the transmission reliability of wireless communication systems. In this paper, one such cross‐layer design scheme that combines physical layer adaptive modulation and coding (AMC) with link layer truncated automatic repeat request (T‐ARQ) is proposed for multiple‐input multiple‐output (MIMO) systems employing orthogonal space‐‐time block coding (OSTBC). The performance of the proposed cross‐layer design is evaluated in terms of achievable average spectral efficiency (ASE), average packet loss rate (PLR) and outage probability, for which analytical expressions are derived, considering transmission over two types of MIMO fading channels, namely, spatially correlated Nakagami‐m fading channels and keyhole Nakagami‐m fading channels. Furthermore, the effects of the maximum number of ARQ retransmissions, numbers of transmit and receive antennas, Nakagami fading parameter and spatial correlation parameters, are studied and discussed based on numerical results and comparisons. Copyright © 2009 John Wiley & Sons, Ltd.

Error Performance Analysis of Multiuser CDMA Systems with Space-time Coding in Rician Fading Channel

“…According to Refs. [19][20], utilizing (17) and (26), a closed-form approximate expression of average SER of multiuser space-time coded CDMA system with MPSK modulation is obtained as: It is well known that the CDMA system performance with quasi-orthogonal spreading code is worse than that with orthogonal spreading code. Namely, the BER of the former is higher than that of the latter, and the corresponding effective SNR (denoted by G , 2 G , X code) can be easily obtained.…”

“…Hence, it is necessary to extend the STBC scheme into multiuser CDMA scenario for practical purposes. Based on different multiuser spacetime coded system models, the receiver schemes are designed in references [11][12][13][14][15][16][17][18] and references therein. In reference [11], the bit error rate (BER) analysis is provided for space-time coded CDMA system with the conventional matched filter receiver, but the analysis method and system model are applicable only to the BPSK modulation and downlink, and does not provide the closed-form BER expression for Rician fading channel.…”

“…Blind space-time multiuser detection schemes are presented in reference [16] for MC-CDMA system. The performance of space-time coded MIMO system with cross-layer design is analyzed in spatially-correlated and Keyhole Nakagami fading channel [17], but the analytical method is applicable only to single user system. Reference [18] gives the effective combination of CDMA system and different space-time codes, and the developed decorrelative receiver scheme can decouple the detection of different users, but the decoding complexity is exponential for each user, which will not benefit practical application.…”