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.

中文翻译：

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使用多个接收天线方向评估EAR间隔天线性能

赤道大气雷达（EAR）是一种非常高频率（VHF）的多普勒雷达，其有源相控阵天线系统工作于47 MHz。自2001年在印度尼西亚西苏门答腊省科托邦的赤道建立以来，它最初配备了单个接收通道系统（0.20°S，100.32°E）。通过开发使用通用软件无线电外围设备（USRP）和GNU无线电的多通道接收器，最近的进展已使EAR上的间隔天线（SA）方法得以实现。但是，这种方法表现出有限的高度观测和水平风估计精度。在这里，我们考虑了接收天线的尺寸及其分离距离，对五种不同方向的EAR SA性能进行了比较和分析。在2019年4月至9月之间进行了所选配置的实验，并使用全相关分析（FCA）估算了水平风廓线，并将其与EAR标准数据进行了比较。另外，针对所有配置执行具有最小二乘法的FCA，以提高估计精度。根据结果​​，具有最大孔径的配置相对于其他四种配置具有明显的优势，但是在最大可观察高度方面的改进有限。