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Recent works have identified hybrid analog-digital processing as a cost-effective alternative to conventional full-digital processing in massive multiple-input multiple-output (MIMO) systems owing to the deployment of far less number of radio frequency (RF) chains. In this paper, we analyze the impact of oscillator phase noise on hybrid precoding in massive MIMO systems. Relying on the time division...
This paper investigates the performance of bidirectional dynamic networks (BDN) with massive multiple input multiple output (MIMO) systems. In BDN, dynamic allocation of the number of uplink and downlink remote radio heads (RRHs) is proposed, which offers a flexible solution to balance the data traffic asymmetry without requiring the time synchronization. Intuitively, the interference between the...
In this paper, we study the uplink (UL) and downlink (DL) ergodic capacity in the bidirectional dynamic network (BDN). By dynamically allocating the numbers of UL and DL remote radio heads (RRHs), BDN facilitates simultaneous UL and DL communications to accommodate the data traffic asymmetry. Assuming that the number of antennas at each RRH (M) is large, we derive the closed-form expressions for the...
Scaling up the conventional multiple-input multiple- output (MIMO) by orders of magnitude, massive MIMO technique brings huge improvement in spectrum efficiency and energy efficiency. However, under time- division duplex (TDD) operation, the reciprocity calibration need to be necessarily investigated, since the mismatches of the transceiver radio frequency (RF) circuits at both sides of the link will...
When both access points (APs) and user equipments (UEs) have multiple antennas, the block diagonalization (BD) precoding is preferred for the distributed large-scale multiple-input multiple-output (MIMO) systems. In time division duplexing (TDD) operation, the APs can exploit the estimated uplink channel for downlink joint precoding transmission to simultaneously serve multiple UEs, due to the principle...
For multicell MIMO interfering broadcast channels (IFBC), the zero-forcing-based approach can achieve the near optimal performance at high signal-noise-ratio (SNR) regime. However, the drawback of the zero-forcing-based approach is the poor performance in low SNR regime compared to the conditional match filter receive scheme. In order to address this problem, we propose an algorithm for minimizing...
Mutual coupling effect is an important electromagnetic interaction between the antennas, which cannot be neglected for massive multiple-input multiple-output (MIMO) antenna systems. In time division duplex (TDD) mode, it is necessary to perform reciprocity calibration, because the mismatches of transceiver radio frequency (RF) circuits at both sides of the link make the whole communication channel...
We consider the downlink multi-user multi-cell massive MIMO systems, and our system model accounts for channel estimation, pilot contamination, and uniformly random user location distribution. An equivalent channel model is investigated which indicates that the users in various cells come through the same ‘fast fading’ when they reuse the same training signal in uplink pilot transmission phase. Assuming...
In massive multiple-input multiple-output (MIMO) systems, idle users may passively overhear the signal transmitted to the intended user, known as internal eavesdroppers. In order to improve the secrecy performance, artificial noise (AN) is used jointly with maximum ratio transmission (MRT) precoding. Since the idle users can be anywhere in the cell, we investigate the secrecy outage probability for...
We consider the downlink multi-user multi-cell massive MIMO systems, assuming that the number of antennas at base station (BS) and the number of users are large. Our system model accounts for channel estimation, pilot contamination, and uniformly random user location distribution. We derive the approximation of area spectral efficiency (ASE) with regularized zero-forcing (RZF) precoding technique...
In this paper, a channel estimation (CE) and precoding scheme by using H-infinity (H-inf) criterion for mitigation of pilot contamination (PC) in Massive multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems is reconsidered. Firstly, different thresholds in H-inf CE and precoding are considered. Secondly, asymptotic analysis of the large system is applied...
We consider the uplink of a multi-cell multiuser multiple-input multiple-output time-division duplexing (TDD) system. The data detection is done by using MMSE filer taking pilot contamination into consideration. Employing the equivalent channel model of MMSE channel estimation, we find an interesting characteristic of user's SINR. In view of the characteristic, we derive new, exact closed-form expressions...
This paper investigates the uplink performance of multiple-input multiple-output (MIMO) wireless systems employing linear minimum mean-squared error (MMSE) receivers. We focus on multi-cell MU-MIMO systems with pilot contamination over i.i.d Rayleigh fading channels. The MMSE estimator is adopted to get the CSI and we build the equivalent model of estimated channel for MU-MIMO system with pilot contamination...
In this paper, we study iterative detection algorithms of the multi-cell multi-user massive MIMO systems with pilot contamination. First, a iterative algorithm applying soft decision interference cancellation is introduced. It is based on minimum mean square error (MMSE) filter and derived from [1] where it was applied in block transmission. Then, by considering the algorithm complexity, two iterative...
In this paper, the uplink sum-rate of the multi-cell multi-user massive MIMO system is studied under correlated Rayleigh fading channels. First, by considering pilot contamination effect, the equivalent system model of the massive MIMO is given with MMSE channel estimation. Then, the lower bound of the sum-rate is derived, and its asymptotical performance is studied when the base station antenna number...
The spectral efficiency of multi-cell multi-user distributed antenna system with imperfect channel state information (CSI) is studied in this paper. First, considering the pilot contamination and minimum mean-squared-error (MMSE) channel estimation, the equivalent channel model is presented and the sum-rate of the uplink transmission is derived. Under a physical channel model, the equivalent channel...
Transmit diversity (TD) is an efficient method to yield channel capacity in single-user multi-antenna system. In this paper, we first analyze scheduling based on TD in multi-user distributed antenna systems (DAS). We show that average throughput of the system grows with the total number of remote access units (RAUs) in DAS. However, when the total number of RAUs is constant, TD has little improvement...
In this paper, the capacity of MIMO relay channel with decode and forward (DF) scheme is investigated, where each node within the system quipped with multiple antennas and located in an environment with distance-dependent path loss. In order to achieve the maximum capacity of the system, the optimal power allocation (OPA) among the nodes and the transmit antennas is analyzed under the assumption that...
A joint channel estimation and data detection scheme by using Markov chain Monte Carlo (MCMC) is proposed for MIMO-OFDM systems with multi-tone narrow-band interference (MTNBI). The channel impulse response, the noise variance and the indicator of the impulse noise can be estimated accurately, and then the receiver knows whether the signal is interfered by the narrow band interference. One of the...
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