A novel planar antenna array for a ground-based synthetic aperture radar

Abstract

A MIMO GB-SAR system called MELISSA was put in place to monitor landslides in Italy and the sinking of the Costa Concordia cruise liner in France. It comprises 12 pyramidal horn antennas placed in a linear geometry for transmission, and these are used in the detection of the motion of a target (for example a landslide or other terrestrial deformation). The low half power beam width (19.76° at θ = 90°) of the transmitting radiation pattern of MELISSA results in low coverage area of the target. This paper proposes two alternative types of horn antenna for the current transmitter module of MELISSA, namely the cantenna and coaxial cavity horn antenna, for installation in a 2×6 planar antenna array. A higher value of the 3 dB beamwidth is observed using these arrays (38.320 at θ = 90° and 104.80 at φ = 0° for the cantenna array and 410 at θ = 90° and 140.40 at φ = 0° for the coaxial cavity horn antenna array). The overall gain of the proposed systems is around 10 dBi, and the efficiencies are between 85% and 90%. Using the Dolph Chebyshev beamforming technique on the proposed antenna arrays yields a zero sidelobe level, which improves the overall peak sidelobe ratio of the system and in turn the quality of the images obtained. Our proposed design for the transmitting section of the MELISSA system has applications terrestrial deformation monitoring with higher area coverage.

Antenna Array for Ku-Band MIMO GB-SAR

“…Recently, multi-input multi-output (MIMO) radar has attracted much attention as an alternative to the mechanical GB-SAR [10][11][12][13][14][15][16][17]. The development of new MIMO antenna configurations for radar systems to monitor large areas is demanded.…”

“…A 6 × 6 folded dipole MIMO antenna working at the C-band was used to configure a MIMO radar to synthesize an equally spaced virtual array of 36 elements [16]. A 2 × 6 planar MIMO antenna with coaxial cavity horn elements was used to construct a MIMO radar system with great area coverage [17]. All these researches employed horn antennas as transmitting and receiving sensors, and they occupy large areas.…”