Evaluation of EAR Spaced Antenna Performance Using Multiple Receiving Antennas Orientations

Abstract

Equatorial Atmosphere Radar (EAR) is a very high frequency (VHF) Doppler radar with an active phased array antenna system operating at 47 MHz. It had originally been equipped with a single receiving channel system since its establishment in 2001 at the equator in Kototabang, West Sumatra, Indonesia (0.20 • S, 100.32 • E). Recent progress has enabled the implementation of a spaced antenna (SA) method on the EAR through the development of a multichannel receiver using Universal Software Radio Peripheral (USRP) and GNU Radio. However, this approach exhibits limited height observation and horizontal wind estimation accuracy. Here, we present comparison and analysis of EAR SA performance with five different orientations, taking into consideration the size of the receiving antennas and their separation distance. Experiments with the chosen configurations were carried out between April and September 2019, and the horizontal wind profiles were estimated using full correlation analysis (FCA) and compared with the EAR standard data. In addition, FCA with the least squares method is carried out for all configurations with the aim of improving the estimation accuracy. Based on the results, the configuration with the largest aperture shows a clear advantage over the other four configurations but with limited improvement in terms of maximum observable height.

Multi‐Receiver Augmentation to Advanced Indian MST Radar (AIR)—Implementation of Spaced Antenna Technique

“…The comparison of winds presented in the present study are on par with those reported in earlier studies made elsewhere with correlation coefficients in the range of 0.85–0.96 for zonal and meridional winds (or wind speeds) (Aris et al., 2020; Engler et al., 2008; Hocking, 1997; Kumar et al., 2014). Though winds derived by both the radar techniques, DBS and SA, correlates well with those derived by radiosonde with R 2 > 0.9, the correlation of winds between SA and radiosonde is marginally superior than that between DBS and radiosonde.…”

“…Several studies have shown that the performance of these different variants is similar to that of FCA (Chau & Balsley, 1998; Doviak et al., 2004; Kumar et al., 2014). The impact of distance between receiving antennas on wind estimation has been studied by combining arrays in a variety of ways (Aris et al., 2020; Holdsworth & Reid, 1997; Kumar et al., 2013; Praskovsky et al., 2004). Longer distance between receiving antennas decorrelates the signal, while the shorter distance causes underestimation of winds (triangle size effect).…”

A Lens Antenna with Reconfigurable Beams for mmWave Wind Profile Radar

“…Similar technology of wind profiles has been explored for forecasting weather [4][5][6]. In the WPR (Wind Profile Radar), magnitudes and directions of the wind speed are both detected via the antenna with multiple radiation beams pointing to different spatial directions [7][8][9]; thus, DBS (Doppler Beam Steering) antenna [10,11], which requires large-scale phased array antennas, and the Spaced Antenna (SA) antenna [12,13], which resembles MIMO (Multiple-Input Multiple-Output) with setting up several transmitting and receiving antennas, are the typical two types of antenna. In terms of DBS antennas, as shown in [14,15], scanning beams are available but with a mechanical method or multiple antennas.…”