Applications to Heterogeneous Integrated Phased Arrays

Phased arrays play a crucial role in modern wireless communication systems due to their fantastic abilities to shape, switch, and/or steer the radiation beam of antennas. Without using digital signal processing units, beam‐switching, beam‐steering, and even multi‐beam arrays can be realized at microwave and millimeter‐wave frequencies using RF circuit components. This chapter introduces several innovative heterogeneous integrated phased array systems. It involves beam‐switching array, Van Atta array, reflection‐type retrodirective array, and phase‐conjugating array. The chapter discusses dual‐mode retrodirective arrays, enabling dual‐band operation for increasing the data throughput and high quality of service. A heterogeneous integrated phased array functioning as a Butler matrix and a reflection‐type retrodirective array respectively in two different bands follows. A tri‐mode heterogeneous integrated phased array, serving as a beam‐switching array, a Van Atta array, and a phase‐conjugating array respectively in the low, mid, and high bands, is then implemented and demonstrated. A simplified version using two antenna elements is then discussed.