Performance evaluation of quasi-cyclic LDPC codes for IEEE802.11n based MIMO-OFDM systems

Abstract

This paper focuses on the study of low density parity check (LDPC) coded Multiple-Input Multiple-Output (MIMO) systems for high throughput wireless communication. The evaluation and implementation of quasi-cyclic LDPC (QC-LDPC) code in MIMO-OFDM systems are presented. QC-LDPC has comparative error correcting performance with random LDPC and considerably reduces complexity. We evaluate the communication performance of the QC-LDPC coded system based on the IEEE802.11n standard using a 2x2 MIMO scheme.

Performance optimization of iterative receiver for wireless communications based on realistic channel conditions

“…However, to achieve a certain performance level, a minimum number of iterations is required. This number was obtained by simulations in [31]. Thus, in this paper, we choose the best achievable bit error rate performance with fixed iteration loops as a criterion and try to optimize the iteration loops.…”

“…For only adapting iterative detection or decoding, by using the method in [31] for an IEEE 802.11n system, that at least five and two iterations are needed for decoding and detection, respectively, for a packet error rate of 10 −2 . Then, for the bidirectional receiver structure, simulation results are shown for a 4 × 4 MIMO OFDM system.…”

“…Let us now compare the performance of the newlyproposed iterative receiver with optimized numbers of detection and decoding iterations with the conventional noniterative receiver [27] and with the iterative receiver with fixed numbers of iterations [27,28] (40 detection and decoding iterations in total as mentioned in [31] as well). Fig.…”

“…In [20] we have shown that QC-LDPC can approach the bit-error-rate performance of random-structured LDPC [17]. Fig.…”