The effect of group-delay difference for wideband antenna arraying: Degradation and its solution

Abstract

Antenna arraying, which is an important approach for weak signal reception, can effectively improve the received SNR. For wideband signal arraying, group-delay difference between antennas may lead to great combining loss. In this paper, the effect of group-delay difference between antennas on combining SNR is studied. A frequency domain division method, which divides each path of the received signal into several narrowband sub-blocks and accomplishes arraying respectively, is proposed to minimize the arraying degradation. Compared with SIMPLE algorithm, phase compensation effect is investigated via MMSE method. Numerical results show that the proposed method could almost eliminate the effect of group-delay difference and effectively reduce the combining loss.

An Improved Antenna Group Delay Measurement Method Using a Three-antenna Extrapolation Technique

“…With the development of satellite navigation, remote sensing, modern communication, et al, antenna group delay (GD) is paid more and more attentions nowadays. Especially for global navigation satellite systems (GNSS), antenna GD measurement accuracy will set the boundaries of how well it will perform [11][12][13][14][15]. The group delay of the antenna versus aspect angle is defined in the standard of Radio Technical Commission for Aeronautics (RTCA), and its limit is also specified from 0.65 ns to 2.5 ns related to the elevation angle at GPS L1 frequency (1575.42 MHz) which shows the requirements for high accuracy antenna GD measurement [16].…”