Distributed Beamforming and Power Allocation for Heterogeneous Networks with MISO Interference Channel.

Kisong Lee

doi:10.3390/s21082606

Abstract

To address the limitations of centralized resource allocation, i.e., high computational complexity and signaling overhead, a distributed beamforming and power allocation strategy is proposed for heterogeneous networks with multiple-input-single-output (MISO) interference channels. In the proposed scheme, each secondary user transceiver pair (SU TP) determines the beamforming vector and transmits power to maximize its own spectral efficiency (SE) while keeping the interference to the primary user below a predetermined threshold, and such resource management for each SU TP is updated iteratively without any information sharing until the strategies for all SU TPs converge. The simulation confirms that the proposed scheme can achieve a performance comparable to that of a centralized approach with a much lower computation time, e.g., less than 5% degradation in SE while improving computation time by more than 10 times.

Highlights

With the explosive growth of mobile data traffic and wireless devices, heterogeneous networks emerged as a promising mechanism to provide high data rates and extend communication coverage [1,2,3]
The nodes are uniformly distributed over an area of 35 m × 35 m with a maximum distance between the Tx and Rx in the same secondary user transceiver pair (SU transceiver pairs (TPs)) of
I.e., wi = khi,i k, and an optimal power allocation is found via an exhaustive search in i,i which the transmit power is quantized into 100 equispaced values, and all possible combinations are examined; Proposed scheme: a distributed power allocation described in Algorithm 1 is utilized h with wi =

Summary

Introduction

With the explosive growth of mobile data traffic and wireless devices, heterogeneous networks emerged as a promising mechanism to provide high data rates and extend communication coverage [1,2,3]. Heterogeneous networks are considered with MISO interference channels, in which multiple SU transceiver pairs (TPs) share the same spectrum with the PUs. In this paper, heterogeneous networks are considered with MISO interference channels, in which multiple SU transceiver pairs (TPs) share the same spectrum with the PUs In such networks, an optimization problem is formulated to find optimal beamforming vectors and transmit powers for the SU TPs to maximize their sum SE with a guarantee of the requirements of allowable interference to the PUs. Given that a centralized approach needs a large signaling overhead and a high computational complexity to determine the suboptimal solutions from the formulated nonconvex problem, a distributed beamforming and power allocation strategy that does not require any information sharing is proposed, where each SU TP determines beamforming vector with the maximum ratio transmission (MRT) and finds transmit power iteratively using dual methods.

System Model and Problem Statement

Distributed Beamforming and Power Allocation

Simulation Results and Discussion

Conclusions