Patent ID: 6510310
Filing Date: 2003-01-21
Classification: H04B

Abstract:
A dual band phone, comprising:an antenna: a transmission path including a first transmit power amplifier and a second transmit power amplifier, the first transmit power amplifier providing transmit signals in a first frequency range and the second transmit power amplifier providing transmit signals in a second frequency range: a first diplexer which receives transmission signals and provides the transmission path with separated transmission signals in the first frequency range to the first transmit amplifier and separated transmission signals in the second frequency range to the second power amplifier; a receive path including a first filter for receiving receive signals in a third frequency range and a second filter for receiving receive signals in a fourth frequency range; a first LNA mixer coupled directly to an output of the first filter; a second LNA mixer coupled directly to an output of the second filter; and a single GaAs transmit-receive switch having a single antenna interface, a transmit input, and a receive output, the antenna interface being coupled to the antenna, the transmit input being coupled to the transmit path, and the receive output being coupled directly to the first and second filters of the receive path, said antenna, transmission path, receive path, and single transmit-receive switch being adapted to allow the dual band phone to operate on GSM and DCS communication bands wherein the transmission path and receive path are used one at a time, the transmission path is used to transmit within one of the first and second frequency ranges and the receive path is used to receive on one of the third and fourth frequency ranges, and wherein the first, second, third and fourth frequency ranges are all different.