A novel low profile Tapered Slot Antenna with absorbing material for radar imaging system

A novel Double Exponentially Tapered Slot Antenna (DETSA) for microwave imaging applications is presented. To extend the antenna´s impedance bandwidth toward low frequency, an absorbing material is stacked on the antenna sides. The measured reflection coefficient |S₁₁| of the antenna confirms that the absorbing material increases the bandwidth as expected. Besides, the radiation pattern is also modified. The mean (θ̅_-3dB) and the standard deviation (σ_θ-3dB) of the -3dB aperture show that antenna with absorbing material exhibits more stable radiation pattern. The time domain characteristics of the antenna are also measured in terms of fidelity factor, transfer function and Full Width at Half Maximum.