Patent ID: 8208866

Claim:
A radio frequency (RF) transceiver front-end comprises: an antenna; an RF receiver section coupled to convert an inbound RF signal into an inbound baseband or near baseband signal; an RF transmitter section coupled to convert an outbound baseband or near baseband signal into an outbound RF signal; a balancing circuit; and a multiple node isolation and coupling circuit comprising a transformer balun having a first winding, a second winding, and a third winding, wherein: the second and third windings are serially coupled, wherein the antenna is coupled to a node of the first winding, the RF receiver section is coupled to a first node of the second winding, the RF transmitter section is coupled to a second node of the third winding, and the balancing circuit is coupled to a series connection of the second and third windings and a plurality of capacitors coupled to the first, second, and third windings, wherein the multiple node isolation and coupling circuit provides the inbound RF signal from the antenna to the RF receiver section and provides the outbound RF signal from the RF transmitter section to the antenna, wherein, by providing an isolating signal to the balancing circuit, the multiple node isolation and coupling circuit substantially isolates the outbound RF signal from the inbound RF signal.