Advanced QRD-M Detection with Iterative Scheme in the MIMO-OFDM System

Abstract

SUMMARYIn this letter, advanced QRD-M detection using iterative scheme is proposed. This scheme has a higher diversity degree than conventional QRD-M detection. According to the simulation results, the performance of proposed QRD-M detection is 0.5dB to 5.5dB better than the performance of conventional QRD-M detection and average iteration time is approximately 1 in the value of M = 1, 2, 3. Therefore, the proposed QRD-M detection has better performance than conventional QRD-M detection, particularly in a high SNR environment and low modulation order.

Low-Complexity QRD-M with Path Eliminations in MIMO-OFDM Systems

“…For further comparisons, Table 3 represents the comparisons for the complexity ratio using 16-QAM modulation in 4 × 4 system. In Table 3, a simplified QRD-M [6], combined QRD-M and Kalman filter [7], a pseudo-inverse-based QRD-M [8], and an advanced QRD-M [9] are compared with the conventional QRD-M and the proposed QRD-M. The error performances for the conventional QRD-M, existing algorithms, and the proposed QRD-M are almost the same.…”

“…In order to justify the better performance for the proposed QRD-M, the complexity for several QRD-M algorithms is compared with the proposed QRD-M. The complexity for the proposed QRD-M is lower than several QRD-M algorithms in [6][7][8][9][10][11][12] because the proposed QRD-M eliminates many unnecessary survival paths due to adaptively calculated thresholds at all layers considering the used modulation scheme. For further comparisons, the complexity for the E-DFE in [16] which has poor error performance is also compared with the proposed QRD-M.…”

“…The main reason for the high complexity of the QRD-M is that it contains unnecessary survival paths among the M survival paths. Several detections were developed to reduce the complexity of the conventional QRD-M in [6][7][8][9][10][11][12][13][14][15]. Among several detections, an adaptive QRD-M was developed in [10], a modified tree structure QRD-M was developed in [11], 2 of 14 and a lattice reduction (LR)-aided adaptive QRD-M was developed in [12].…”

Reduced Complexity of QRD-M Detection Scheme in MIMO-OFDM Systems

“…However, the complexity of ML detection increases exponentially when the number of transmission antennas and modulation set increase. And QR decomposition-M algorithm (QRD-M) has optimal error performance with lower complexity than the ML detection [1]. However, the complexity of the QRD-M also increases exponentially when the number of candidates M, transmission antennas and modulation set increase due to tree structure.…”

Adaptive Power Control Using Large Scale Antenna of the Massive MIMO System in the Mobile Communication

“…Because it effectively compensates interference signals and noise using large scale antenna, it supports theoretical throughput in according to the number of antenna compared to the conventional MIMO systems. As another advantage of the massive MIMO system, although the massive MIMO system uses linear pre-coding scheme and linear detection scheme such as zero forcing (ZF) and matched-filter (MF) with low complexity, it has high reliability in contrast with the conventional MIMO systems [11][12][13][14].…”