Patent ID: 6405025
Filing Date: 2002-06-11
Classification: H04B

Abstract:
A radio communication device such as a radio transceiver operating at least two different frequency ranges having a reception branch for receiving radio signals in one of the frequency ranges and a transmission branch for transmitting radio signals in the same frequency range as receiving radio signals, which device comprises:an antenna and a duplexing means for separating reception and transmission modes of operation and which device further comprises in the reception branch:a first group of bandpass filters, a first group of amplifiers, a second group of bandpass filters and a first mixer, which filters in the first and second group of filters and the first group of amplifiers are arranged so that parallel signal paths for each frequency ranges are defined and where, during reception, a first input signal via the switch is directed to the first group of bandpass. filters and via the first group of amplifiers to the second group of bandpass filters, where a first output signal is directed through the first mixer to a RF circuit of the communication device for further processing, which device further comprises in the transmission branch:a second mixer, a third group of bandpass filters, a second group of amplifiers and a fourth group of bandpass filters, which filters in the third and fourth group of filters and the second group of amplifiers are arranged so that parallel signal paths for each frequency ranges are defined and where, during transmission, a second input signal is directed through the second mixer to the third group of bandpass filters and via the second group of amplifiers to the fourth group of bandpass filters and further as a second output signal via the switch to the antenna which device further comprises:a selecting means for selecting one of the frequency ranges by activating an amplifier in the reception and transmission branch among said first and second group of amplifiers in the signal path corresponding to said frequency range.