Reconfigurable parasitic antennas for compact mobile terminals in multiuser wireless systems

Abstract

This article considers the exploitation of parasitic antenna arrays in multi-user (MU) wireless communication systems by using their adaptive beamforming capabilities in order to improve the average system throughput. The use of parasitic arrays and especially the electrically steerable passive array radiator (ESPAR) antennas enables the design of terminals with a single RF front-end and reduced antenna dimensions, i.e., lightweight and compact mobile terminals. Although the beamforming capabilities of active element arrays at the receiver have been well investigated in the past, this article highlights the potentials of pattern reconfigurable parasitic arrays based on the beamspace representation of the ESPAR antenna. The advantages of using ESPAR at the receiving terminal are examined both in opportunistic beamforming and in MIMO broadcast channel MU systems, optimizing correspondingly the SNR or the SINR of the forward link.

LTE low-cost vertical sectorization through a leaky-wave antenna

“…Radio technology is based on Orthogonal Frequency Division Multiple Access (OFDMA) and it applies sophisticated scheduling and multiple antenna methods. The role of the antenna system performance is thus determinant, and as a result increasing interest is being given to novel multiple antenna schemes [2][3][4][5][6][7][8][9], to increase the Signal to Interference plus Noise Ratio (SINR) and the throughput performance.…”

“…Intelligent/smart antennas [2,3] (based on electronically reconfigurable arrays, either in switched beam mode or in adaptive phased array mode), space-time coding [4], vertical sectorization [6,7], or multiple antenna [3,[8][9][10] techniques have been proposed to increase the capacity gain in 3GPP LTE. As mentioned, LTE aims for simpler and lower-cost solutions.…”

Channel estimation and performance analysis of beamspace MIMO systems

“…Then the authors in [9] demonstrated M orthonormal basis beam patterns to analyse aerial degree of freedom (aDOF) and efficient degree of freedom (eDOF). Later, the authors in [10] applied the beamspace MIMO with ESPAR antenna into multi-user MIMO scenario. The authors proposed channel estimator based on the basic beam patterns in [11].…”

Opportunistic Beamforming Using Dumb Basis Patterns in Cognitive Multiple Access Channels

“…Blind interference alignment was implemented utilizing the reconfigurability feature of the ESPAR antenna in [11]. Other applications of ESPAR antennas in multiuser systems can be found in [12].…”