Antenna Placement Optimization for Distributed Antenna Systems

Abstract

In this paper, we propose new algorithms to determine the antenna location for downlink distributed antenna systems (DASs) in single-cell and two-cell environments. We consider the composite fading channel which includes small and large scale fadings. First, for the single-cell DAS, we formulate the optimization problem of distributed antenna (DA) port locations by maximizing the lower bound of the expected signal to noise ratio (SNR). In comparison to the conventional algorithm based on the squared distance criterion which requires an iterative method, our problem generates a closed form solution. Next, for the two-cell DAS, we propose a gradient ascent algorithm which determines the optimum DA locations by maximizing the lower bound of the expected signal to leakage ratio (SLR). In our work, we consider selection transmission, maximal ratio transmission and zero-forcing beamforming (ZFBF) under sum power constraint and study equal gain transmission and scaled ZFBF under per-antenna power constraint. Simulation results show that our proposed algorithms based on both the SNR and the SLR criteria offer a capacity gain over the conventional centralized antenna systems.Index Terms-Distributed antenna systems, antenna placement.

Downlink Spectral Efficiency of Distributed Antenna Systems Under a Stochastic Model

“…The optimal antenna placement has been dealt with in several previous works, e.g., [8] develops a scheme based on the stochastic approximation theory, and [20] proposes a placement optimization for single-cell and twocell systems by maximizing the lower bound of either SNR or the signal-to-leakage ratio (SLR). However, in this paper the placement of antennas is not an optimization objective.…”

Timing Acquisition with Cooperation of Two Distributed Receive Antennas over Flat-Fading Channels

“…simultaneously be satisfied, the DRX i , which can reach the detection threshold ,1 h T  , must be verified to ensure the false alarm probability at DRX i is not higher than the pre-defined σ σ ≈ , the detection threshold is set according to (4) and (6). From reference [21], we consider the path loss and shadowing model, i.e., , 0 10 lg 10 lg , 1, 2…”

Composite vector quantization for optimizing antenna locations

“…The system performance improvements of the DAS in terms of power saving and spectral efficiency highly depend on the locations of its RAUs [3,[5][6][7]. Several papers analyzed the performance of DASs with fixed RAU locations for various transmit strategies for uplink or downlink.…”

“…Similarly, an SNR criterion is used for a DAS with multiple-antenna ports in [14]. In [7], the authors extend the SDC results to single-and two-cell DASs with ST, maximal ratio transmission (MRT), and zero-forcing beamforming under sum power constraint by maximizing a lower bound of the expected SNR. In [15], the authors place RAUs in a circular layout and estimate the optimal radius of the antenna layout that maximizes the sum rate.…”