A high-directivity phased array for secure transmission

A high-directivity phased array using combination of beam-steering technique and novel null tracking technique for secure signal transmission is presented. The proposed phased array provides super high directivity and constant data beamwidth for a wide scanning angle without alternating transmitting power. It achieves that by generating jamming signal with a null towards the direction of data signal´s beam as well as a stable twin-beam tracking with the null. A 3×4 antenna array prototype is designed and fabricated. It demonstrates high signal-to-noise ratio directivity of over 25 dB, as well as a constant data beamwidth (S/N >12 dB) of 15° and a large jamming window (S/N <;0 dB) to interfere the spy receivers for a wide scanning angle between ±27° for GSM1800 application.