ملخص الدراسة:

Multiple-Input-Multiple-Output (MIMO) communication techniques have been an important area of focus for 4th generation wireless systems. This is mainly because of their potentials for high capacity, increased diversity, and interference suppression. There are many schemes that can be applied to MIMO systems such as Space-Time Block Codes (STBCs), Space-Time Trellis Codes (STTCs), and the Vertical Bell Labs Space-Time Architecture (V-BLAST). STBC and STTCs are used for diversity gain while VBLAST is used for capacity advantage. There are many types of detection techniques were introduced for spatial multiplexing MIMO channels. Vertical Bell Labs Space-Time Architecture/ Maximum A-Posteriori (V-BLAST/MAP) is a new symbol detection algorithm for MIMO channels, which is an extension of the well-known V-BLAST algorithm. Another algorithm which is a V-BLAST/MAP, algorithm combines elements of the V-BLAST algorithm and the maximum a-posteriori (MAP) rule. The performance improvement is significant. Simulations show that V-BLAST/MAP achieves symbol error rates close to the optimal maximum likelihood (ML) scheme while retaining the low-complexity nature of the V-BLAST. In the nineties, a novel method of coding that has become known as Turbo Coding was developed. Turbo coding introduced to prevent or reduce the effects of burst error by using several convolutional coders and a random interleaver. Turbo Coding has proved to be the most efficient code developed so far, capable of operating close to the Shannon limit with a reasonable complexity. Recently, some of high potential research considers the case of using principle of iterative (‘Turbo processing’) in improving the performance of multiple antenna systems. One of the resulting classes of MIMO system referred to as Turbo-V-BLAST. Therefore, Turbo codes with independent fading coefficients at each coded bit in a codeword will get the best performance. In this research, the performance of Turbo-V-BLAST algorithm with different types of detection is evaluated. First, the V-BLAST algorithm with zero forcing (ZF), Linear Least Square Estimation (LLSE) and MAP detections is reviewed and the error rate of this algorithm is investigated. Next, the V-BLAST algorithm is combined with Turbo code and the performance of Turbo-V-BLAST algorithm with ZF, LLSE and MAP detections was evaluated. Then, the novel approach of using MAP detection technique with Turbo-V-BLAST is introduced . The performance of the new algorithm is derived.

توثيق المرجعي (APA)