A Low-Complexity Sub-Optimal Decoder for OSTBC-Based Mobile Cooperative Systems

作者:Khattabi Yazid*; Matalgah Mustafa M
来源:IEEE Wireless Communications and Networking Conference (WCNC), 2016-04-03 to 2016-04-07.

摘要

paper, we consider an amplify-and-forward (AF) wireless cooperative-diversity system with Alamouti-type orthogonal-space-time-block-code (Alamouti-OSTBC) transmission at the source under the influence of the cooperating nodes' mobility. The system's links are characterized by Rayleigh frequency-flat (narrowband) and, due to nodes' mobility, time-selective (i.e., rapidly time-varying) fading channels. We first employ the conventional Alamouti's decoder (ALD) at the system's destination and show that the time-selective fading destroys its orthogonality and optimality as a result of its output's interfering and correlated decision statistics, which causes a severely degraded system symbol error probability (SEP) performance with error floors. In order to overcome with this impact, we propose and design a sub-optimal decoder (SOD) that could be employed instead of the ALD, which is capable of providing non-interfering (but still correlated) decision statistics even though the fading links are time-selective. The SEP performance analysis of this proposed SOD shows considerable improvement over that of the ALD with no error floors and without the need of any additional decoding complexity. Numerical results along with practical link-level simulations are provided to validate the accuracy of the presented analysis and to demonstrate the system performance.

  • 出版日期2016