Asymptotic Analysis of MRT Over Double Scattering Channels With MMSE Estimation

Abstract

This paper studies the ergodic rate performance of maximum ratio transmission (MRT) precoding in the downlink of a multiuser multiple-input single-output (MISO) system, where the channel between the base station (BS) and each user is modeled using the double scattering model. We utilize the minimum-mean-square-error (MMSE) channel estimate for this model, which is used in the design of the MRT precoding. Within this setting, we are interested in deriving tight approximations of the ergodic rate under the assumption that the number of BS antennas (N), the number of users (K) and that of scatterers (S) grow large with the same pace. These approximations are expressed in simplified closedform expressions for the special case of multi-keyhole channels. They reveal that unlike the standard Rayleigh channel in which the SINR grows as O N K , the SINR associated with a multi-keyhole channel scales as O S K. This particularly shows that the reaped gains of the large-scale MIMO over double scattering channels do not linearly increase with the number of antennas and are limited by the number of scatterers. We further provide simulation results that confirm the close match provided by the asymptotic analysis for moderate system dimensions and provide some useful insights into the interplay between N , K and S.

Uplink Power Control in Massive MIMO With Double Scattering Channels

“…Lemma 2 shows the concrete expression of the channel estimate of each user together with the statistical information, which are used to formulate the combining vectors and computing the closed-form expression on the uplink ergodic SE hereafter. It should be noticed that our channel estimation considers the influence of coherent interference caused by the pilot contamination in multi-cell Massive MIMO scenarios, which is a generalization of the previous result in [18], [19] that assumed the orthogonal pilot signals for all the users in a single cell. Along with the statistical information in Lemma 1, the channel estimates and estimation errors in Lemma 2 are utilized to compute the closed-form uplink SE expression hereafter.…”

“…The first work numerically studying the uplink ergodic SE of cellular Massive MIMO systems with the double scattering channels (spatially correlated and rank-deficient) was found in [17]. For theoretical analysis, the authors in [18], [19] computed the asymptotic ergodic SE of a single-cell Massive MIMO system with the different linear precoding techniques when the number of BS antennas, scatterers, and users grow large with the same rate. It is worth emphasizing that these works assumed each user utilizing an orthogonal pilot signal in a single-cell system and the formulations are asymptotically established.…”

Massive MIMO under Double Scattering Channels: Power Minimization and Congestion Controls

“…Lemma 1 shows the concrete expression of the channel estimate of each user. Our channel estimation considers the influence of pilot contamination in multi-cell massive MIMO scenarios, which is a generalization of the previous result in [9], [10] that assumed the orthogonal pilot signals for all the users in a single cell.…”

“…The first work numerically studying the uplink ergodic SE of cellular massive MIMO systems with the double scattering channels was found in [8]. For theoretical analysis, the authors in [9], [10] computed the asymptotic The work of T. V. Chien, S. Chatzinotas, and B. Ottersten was supported by FNR, Luxembourg under the COREproject C16/IS/11306457/ELECTIC (Energy and CompLexity EffiCienT mIllimeter-waveLarge-Array Communications). The work of H. Q. Ngo was supported by the UK Research and Innovation Future Leaders Fellowships under Grant MR/S017666/1.…”

Performance Analysis of MIMO-HARQ Assisted V2V Communications With Keyhole Effect

“…In [18], a statistical analysis of signal-to-noise ratio (SNR) was carried out for MIMO keyhole channels by considering double-Rayleigh and double-Nakagami-Rice fadings. In [19], the authors derived the deterministic approximation for the ergodic rate of a large scale MISO system over keyhole fading channel, where the maximum ratio transmission (MRT) precoding was adopted. Furthermore, the impact of the keyhole channels on satellite communications has been studied in [20].…”