Patent ID: 8432836

Claim:
Wireless communications circuitry configured to operate in different communications bands without producing excessive interference between the different communications bands, comprising: a first radio-frequency transmitter that operates in a first transmit communications band; a second radio-frequency transmitter that operates in a second transmit communications band; a radio-frequency receiver that operates in a receive communications band; an antenna that is shared by the first and second radio-frequency transmitters and the radio-frequency receiver; a circulator; a first path coupled between a first port of the circulator and the antenna, wherein the first path conveys signals in the first transmit communications band, the second transmit communications band, and the receive communications band; a second path coupled between a second port of the circulator and the radio-frequency receiver that conveys signals in the receive communications band; and a third path coupled to a third port of the circulator that conveys signals in the first and second transmit communications bands, wherein the circulator is configured to route the signals in the first and second transmit communications bands from the third path to the first path, to route the signals in the receive communications band from the first path to the second path, and to isolate the radio-frequency receiver from noise on the third path.