Simple Structure Efficient Full-Rate STBC for LTE-Advanced System over Correlated Rayleigh Fading Channel with Simple Decoder
Paper ID : 1091-IST
1Ali Kuhestani, 2Abbas Mohammadi *
1Department of electrical engineering
An efficient full-rate linear dispersion (LD) code is designed over correlated Rayleigh fading channel. This code is suitable for mobile station in LTE-Advanced system where a code with two antennas and three time slots is required and the orthogonal Alamouti code can not be applied. For this purpose, we first derive a closed-form formula for the ergodic achievable information rate of an LD coded multi-input multiple-output (MIMO) system over correlated Rayleigh fading channel. This formula is a closed-form solution of integrals if the special functions are included. Then, we construct a cost function and using an exhaustive search, we design an efficient full-rate LD code. The designed code has elegant features such as full-rate, minimum power fluctuation, simple structure and simple decoder (decoding of real and imaginary parts of each symbol, separately) at the receiver. Simulation results show that the proposed code provides better bit error rate (BER) performance than the best known scheme, AV code (its maximum likelihood (ML) decoding requires a joint detection of three real symbols), for BER > 4 × 10−3 over correlated Rayleigh fading channel. Moreover, it outperforms AV code at practical signal-to-noises (SNRs) when both the STBCs are concatenated with a simple outer encoder. Furthermore, the proposed code has more achievable information rate than the proposed codes in the literatures at all SNRs.
Linear dispersion (LD) code, LTE-Advanced, Achievable information rate, Correlated Rayleigh fading MIMO channel