UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Exploiting Known Interference as Green Signal Power for Downlink Beamforming Optimization

Masouros, C; Zheng, G; (2015) Exploiting Known Interference as Green Signal Power for Downlink Beamforming Optimization. IEEE Transactions on Signal Processing , 63 (14) pp. 3628-3640. 10.1109/TSP.2015.2430839. Green open access

[thumbnail of 07103338.pdf]
Preview
Text
07103338.pdf

Download (2MB) | Preview

Abstract

We propose a data-aided transmit beamforming scheme for the multi-user multiple-input-single-output (MISO) downlink channel. While conventional beamforming schemes aim at the minimization of the transmit power subject to suppressing interference to guarantee quality of service (QoS) constraints, here we use the knowledge of both data and channel state information (CSI) at the transmitter to exploit, rather than suppress, constructive interference. More specifically, we design a new precoding scheme for the MISO downlink that minimizes the transmit power for generic phase shift keying (PSK) modulated signals. The proposed precoder reduces the transmit power compared to conventional schemes, by adapting the QoS constraints to accommodate constructive interference as a source of useful signal power. By exploiting the power of constructively interfering symbols, the proposed scheme achieves the required QoS at lower transmit power. We extend this concept to the signal to interference plus noise ratio (SINR) balancing problem, where higher SINR values compared to the conventional SINR balancing optimization are achieved for given transmit power budgets. In addition, we derive equivalent virtual multicast formulations for both optimizations, both of which provide insights of the optimal solution and facilitate the design of a more efficient solver. Finally, we propose a robust beamforming technique to deal with imperfect CSI, that also reduces the transmit power over conventional techniques, while guaranteeing the required QoS. Our simulation and analysis show significant power savings for small scale MISO downlink channels with the proposed data-aided optimization compared to conventional beamforming optimization.

Type: Article
Title: Exploiting Known Interference as Green Signal Power for Downlink Beamforming Optimization
Open access status: An open access version is available from UCL Discovery
DOI: 10.1109/TSP.2015.2430839
Publisher version: http://dx.dpoi.org/10.1109/TSP.2015.2430839
Language: English
Additional information: This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/
Keywords: Constructive interference, convex optimization, downlink beamforming, power minimization, SINR balancing
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Electronic and Electrical Eng
URI: https://discovery.ucl.ac.uk/id/eprint/1468400
Downloads since deposit
209Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item