Power Minimization in Multi-tier Networks with Flexible Duplexing

Abstract

In this paper we present an algorithm to minimize transmit power in multiple-input multiple-output (MIMO) heterogeneous networks (HetNets) with flexible duplexing, a promising strategy that allows the coexistence of uplink and downlink cells within the same time and frequency resource block. First, the proposed algorithm minimizes transmit power for a given uplink/downlink (UL/DL) combination, and afterwards, the optimal solution out of the explored UL/DL combinations is selected. To reduce the computational cost of exploring all the UL/DL settings, we propose a hierarchical switching (HS) approach that considers a reduced subset of transmit directions. By means of Monte Carlo simulations, we show that the proposed technique provides significant power savings with respect to a conventional time-division duplex (TDD) scheme.

Experimental evaluation of flexible duplexing in multi-tier MIMO networks

“…In this model, a partial bandwidth overlap is allowed among uplink and downlink frequency-division duplex (FDD) slots, and the data rate is optimized subject to power constraints, so as to determine user scheduling as well. Finally, a power minimization algorithm is proposed in [13] to optimize the total transmit power for a given UL/DL combination, and then combined with the HS approach in [9] to select the best duplexing configuration.…”