A 27-to-31.6 GHz 8-Element Phased-Array Transmitter Front-End with Inter-Element-Interference Cancellation Scheme in 65 nm CMOS.

Millimeter-wave (mm-wave) phased-arrays have demonstrated great potential in 5G, satellite communication, radar applications. However, their compact element arrangement makes them highly susceptible to the influence of other elements, especially in the case of large array elements with a narrow beamwidth. The strength of signal in transmitters (TXs) is commonly stronger than that in the receivers (RXs), resulting in greater influence. In this work, an interelement-interference cancellation (IEIC) scheme is introduced to cancel coupling caused by phase-shifting between elements. A 27-to-31.6 GHz 8-element phased-array transmitter front-end (FE) is proposed to validate this scheme. By implementing this scheme, the coupling can be reduced by 20 dB, proving its effectiveness.