scholarly journals Performance Analysis of Large-Scale MU-MIMO With a Simple and Effective Chanel Estimator

2019 ◽  
Author(s):  
Felipe Augusto Pereira de Figueiredo ◽  
Claudio Ferreira Dias ◽  
Eduardo Rodrigues de Lima ◽  
Gustavo Fraidenraich
Keyword(s):  
Mean Square Error ◽  
Spectral Efficiency ◽  
Massive Mimo ◽  
Large Scale ◽  
Mimo Systems ◽  
Minimum Mean Square Error ◽  
Noise Power ◽  
Mean Square ◽  
Pilot Contamination ◽  
Channel Estimator

Accurate channel estimation is of utmost importance for massive MIMO systems that allow providing significant improvements in spectral and energy efficiency. In this work, we investigate the spectral efficiency performance and present a channel estimator for multi-cell massive MIMO systems subjected to pilot-contamination. The proposed channel estimator performs well under moderate to aggressive pilot contamination scenarios without prior knowledge of the inter-cell large-scale channel coefficients and noise power. The estimator approximates the performance of a linear Minimum Mean Square Error (MMSE) as the number of antennas increases. Following, we derive a lower bound closed-form spectral efficiency of the Maximum Ratio Combining (MRC) detector in the proposed channel estimator. The simulation results highlight that the proposed estimator performance approaches the linear minimum mean square error (LMMSE) channel estimator asymptotically.

scholarly journals On the Distribution of an Effective Channel Estimator for Multi-Cell Massive MIMO

2019 ◽  
Author(s):  
Felipe Augusto Pereira de Figueiredo ◽  
Claudio Ferreira Dias ◽  
Fabbryccio A. C. M. Cardoso ◽  
Gustavo Fraidenraich
Keyword(s):  
Massive Mimo ◽  
Large Scale ◽  
Mimo Systems ◽  
Base Station ◽  
Noise Power ◽  
Pilot Contamination ◽  
Channel Estimator ◽  
Symmetric Complex ◽  
Mmse Estimator ◽  
Effective Channel

Accurate channel estimation is of utmost importance for massive MIMO systems to provide significant improvements in spectral and energy efficiency. In this work, we present a study on the distribution of a simple but yet effective and practical channel estimator for multi-cell massive MIMO systems suffering from pilot-contamination. The proposed channel estimator performs well under moderate to aggressive pilot contamination scenarios without previous knowledge of the inter-cell large-scale channel coefficients and noise power, asymptotically approximating the performance of the linear MMSE estimator as the number of antennas increases. We prove that the distribution of the proposed channel estimator can be accurately approximated by the circularly-symmetric complex normal distribution, when the number of antennas, M, deployed at the base station is greater than 10.

scholarly journals Data Ridden Pilots Based Estimation of Sparse Multipath Massive MIMO Channels Using Orthogonal Matching Pursuit

2019 ◽  
Vol 25 (4) ◽  
pp. 81-87 ◽  
Author(s):  
Babar Mansoor ◽  
Moazzam Islam Tiwana ◽  
Syed Junaid Nawaz ◽  
Abrar Ahmed ◽  
Abdul Haseeb ◽  
...  
Keyword(s):  
Mean Square Error ◽  
Massive Mimo ◽  
Mimo Systems ◽  
Matching Pursuit ◽  
Minimum Mean Square Error ◽  
Research Work ◽  
Base Station ◽  
Orthogonal Matching Pursuit ◽  
Mean Square ◽  
Mimo Channels

Massive Multiple-Input Multiple-Output (MIMO) is envisioned to be a strong candidate technology for the upcoming 5th generation (5G) of wireless communication networks. This research work presents a novel Compressed Sensing (CS) and Superimposed Training (SiT) based technique for estimating the sparse uplink channels in massive MIMO systems. The proposed technique involves arithmetic addition of a periodic, but low powered training sequence with each user’s information sequence. Consequently, separately dedicated resources for the pilot symbols are not needed. Moreover, to attain the estimates of the Channel State Information (CSI) in the uplink, the sparsity exhibited by the MIMO channels is exploited by incorporating CS based Orthogonal Matching Pursuit (OMP) algorithm. For decoding the transmitted information symbols of each user, a Linear Minimum Mean Square Error (LMMSE) based equalizer is incorporated at the receiving Base Station (BS). Based on the obtained simulation results, the proposed SiT-OMP technique outperforms the existing Least Squares (SiT) channel estimation technique. The comparison is done using performance metrics of the Bit Error Rate (BER) and the Normalized Channel Mean Square Error (NCMSE).

scholarly journals An Evaluation of Successive Pilot Decontamination in Massive MIMO

2018 ◽  
Vol 39 (2) ◽  
pp. 107
Author(s):  
Victor Croisfelt Rodrigues ◽  
Taufik Abrão
Keyword(s):  
Spectral Efficiency ◽  
Massive Mimo ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Pilot Training ◽  
Pilot Contamination ◽  
Fundamental Issue ◽  
Data Rates ◽  
Multiple Input ◽  
Input Multiple Output

The demand for higher data rates can be satisfied by the spectral efficiency (SE) improvement offered by Massive multiple-input multiple-output (M-MIMO) systems. However, the pilot contamination remains as a fundamental issue to obtain the paramount SE in such systems. This propitiated the research of several methods to mitigate pilot contamination. One of these procedures is based on the coordination of the cells, culminating in proposals with multiple pilot training phases. This paper aims to expand the results of the original paper, whereby the concepts of large pilot training phases were offered. The evaluation of such method was conducted through more comprehensible numerical results, in which a large number of antennas were assumed and more rigorous SE expressions were used. The channel estimation approaches relying on multiple pilot training phases were considered cumbersome for implementation and an uninteresting solution to overcome pilot contamination; contradicting the results presented in the genuine paper.

OPTIMAL ADAPTIVE PREDICTION FOR MIMO SYSTEMS

2009 ◽  
Vol 18 (03) ◽  
pp. 617-628 ◽  
Author(s):  
BEHNAM SHAHRRAVA
Keyword(s):  
Mean Square Error ◽  
Canonical Form ◽  
Mimo Systems ◽  
Minimum Mean Square Error ◽  
Optimal Solution ◽  
Mean Square ◽  
Adaptive Prediction ◽  
Sample Time ◽  
Priori Knowledge

An adaptive predictor for decouplable systems, which is optimal in the minimum mean-square error sense at each sample time is proposed, based on priori knowledge of the structure of the interactor matrix and a canonical form. The adaptive predictor includes the uncertainty associated with the parameter and state estimates. Moreover, it is shown that no optimal solution to indirect adaptive prediction exists for nondecouplable systems having unknown interactor matrix.

Sign in / Sign up

Export Citation Format

Share Document