An Adaptive Power and Bit Allocation Algorithm for MIMO OFDM/SDMA System Employing Zero-Forcing Multi-user Detection

Abstract

, which operates in a frequency selective fading channel. The zero forcing (ZF) technique is applied to accomplish multi user detection (MUD). A Lagrange multiplier method is applied to obtain a one-step solution for optimal power and bit allocations in this system. The resulting algorithm is advantageous over an alternative Greedy algorithm, because it does not require a timeconsuming iterative procedure for its implementation. The algorithm assigns bits and power for all users according to the channel state information (CSI), which is assumed to be fully or partially available to the transmitter. The simulation results show the proposed algorithm operates successfully in multiple user access scenarios.

MMwave MIMO in 5G Network Analysis for Spectral Efficiency with Beamforming Based Channel Estimation

“…The development of Massive MIMO systems, which have numerous transmitter and receiver antennas and great spectrum and energy efficiency, is a major driver of the adoption of the 5G network [1].Massive MIMO networks have recently captured the attention of many academics, while models for energy augmentation, spectral efficiency, uplink and downlink transmission, and channel estimation have been scrutinised during the past ten years.On the other hand, the massive MIMO system's numerous antennas render the uplink signal assumption ineffective and complicated.In contrast to the conventional uplink detection approach, the suggested method in [2] is effective as well asattains optimal bit error rate (BER), which is based on least-square (LS) channel estimator.As a result, 5G is intended to adapt high reliabilityand to increase SEas well asEE with low latency [3]. Matrix inversion has been avoided by using the Richardson and Neumann series expansion (NSE) approach.Channel is also evaluated based on pilot signals that are sent by user to base stations (BS), while massive MIMO method offers benefits of high reliability, SE and EE.…”