US Patent 11606115 Transmitter signal cancellation in phased array receivers

A method employing an array of antenna elements and a plurality of transceivers, each including (1) a transmitter chain; (2) a receiver chain; and (3) a duplexer having an input electrically connected to the transmitter chain, an output electrically connected to the receiver chain, and a duplexed port electrically connected to a different antenna element, the method involving: identifying among the plurality of transceivers a first and second subsets of transceivers such that together the first and second subsets of transceivers constitute all of the transceivers among the plurality of transceivers; for each transceiver within the first subset of transceivers, but not for the transceivers within the second subset of transceivers, introducing a Φ degree phase shift between the duplexed port of the duplexer and the antenna element to which the duplexed port is electrically connected, wherein Φ=−(2n+1)90°, and wherein n is an integer.