A comparative study of horn antennas suitable for the transmitting antenna array module of MELISSA architecture

The MELISSA system is a ground based aperture radar that has been designed for landslide monitoring in Italy. It consists of a linear antenna array of 12 Pyramidal horn antennas present in the transmitting module of the system and another linear array of 12 receiving Vivaldi antennas. It has been proven that an alternate planar antenna array geometry of 2 × 6 pyramidal horn antennas gives a better performance than the 12 linear horns; present in the transmitting module of MELISSA; in terms of directivity, half power beam width and peak side lobe ratio. This paper aims at presenting a comparative study of peak gains and half power beam widths of various other types of individual horn antenna elements that could be used to replace the conventional pyramidal horn in the earlier proposed 2 × 6 planar configuration and thereby revise the MELISSA system.

I. Introduction

The Synthetic Aperture Radar (SAR) methodology has been enhanced in the form of Mimo Enhanced Linear Short SAR (MELISSA) [1] from the previous Linear Synthetic Aperture Radar System (LISA) [3] being used by the JRC of the European Union for landslide monitoring in Italy. MELISSA is a disaster monitoring system that uses the Multiple Input Multiple Output (MIMO) technique to transmit and receive its waveforms, with a linear array of 12 transmitting horn antennas and another linear array of 12 receiving Vivaldi antennas. This system has been proposed in [1] and claims to have a lower cost and higher performance in terms of LISA. A different antenna array geometry for the 12 transmitting antennas has been proposed and validated using simulations and mathematical calculations in our previous work [2]. It has been observed that placing the 12 transmitting horn antennas in a planar configuration instead of the linear configuration would result in an increase in the Half Power Beam Width (HPBW) to 113.51 degrees and consecutively, an increase in the area of coverage [2]. It has also been proven that the Peak Side Lobe Ratio (PSLR), is least for the planar array configuration, as when compared to the other planar configurations of 3 and Style [2]. This further validates the usage of the planar array configuration.