Reconfigurable Dual Band Bidirectional ReflectionAmplifier with Applications in Van Atta Array

We designed a reconfigurable dual band reflection amplifier with operation frequency bands over 1.8 GHz and/or 2.4 GHz. This one-port amplifier boosts the reflected signal over either of these two frequency bands or both as a dual band reflection amplifier. The amplifier circuit consists of a FET transistor and two PIN diodes which act as switches to form a reconfigurable system. The measured reflection gains at single 1.8 GHz and 2.4 GHz frequency bands are 17.6 dB and 16.75 dB respectively. The dual band operation frequency shows 11.2 dB and 15 dB gain at 1.8 GHz and 2.4 GHz,respectively. Then, we realized a bidirectional amplifier using a dual band -3 dB 90◦ Branch Line Coupler (BLC) integrated with two of the proposed reconfigurable reflection amplifiers.This bidirectional amplifier is a two-port bilateral amplifier.The measured reflection gains show at least 10 dB transmission gains (S21 and S12) at operation frequency bands. The proposed reconfigurable bidirectional amplifier is then used in a dual band Van Atta array. The proposed active retrodirective system outperformed passive Van Atta array by 5 dB gain with only half the number of antenna elements. Each component is investigated analytically and analyzed by Advanced Design System (ADS). Fabricated circuits are measured and show a good agreement with simulations.