Patent ID: 6304748
Filing Date: 2001-10-16
Classification: H04B

Abstract:
A cellular phone for a mobile communications system, said phone being operable at a first radio frequency band and a second radio frequency band, said phone comprising a dual band transmitter and an antenna, said dual band transmitter comprising:a first amplifier, said first amplifier having a first input for a first signal at said first radio frequency, and a first output for an amplified first signal, said first output being connectable to said antenna via a first signal path;a second amplifier, said second amplifier having a second input for a second signal at said second radio frequency band and a second output for an amplified second signal, said second output being connectable to said antenna via a second signal path; anda filter module, said filter module being associated with the first and second signal paths and configured to receive a control signal which selectively operates the filter module at one of a first and second filter characteristics to selectively block undesired frequencies, wherein said first and second filter characteristics are selectable using shared filter components.