A communication system for communicating CDMA and GSM transmit and receive RF information signals through one or more antennas is disclosed. The communication system is comprised of a transmitting unit, a receiving unit, and at least one antenna. The transmitting unit modulates and upconverts a transmit baseband information signal to generate a CDMA transmit RF information signal and a GSM transmit RF information signal. The receiving unit downconverts and demodulates a CDMA receive RF information signal and a GSM receive RF information signal to generate a receive baseband information signal. One or more antennas are coupled to the transmitting unit and receiving unit for transmitting the CDMA transmit RF information signal and the GSM transmit RF information signal, and receiving the CDMA receive RF information signal and the GSM receive RF information signal. The transmitting unit comprises a modulator for modulating a transmit IF LO frequency with the transmit baseband information signal to generate a transmit IF information signal. It also includes a plurality of upconverters for upconverting the transmit IF information signal with a GSM transmit RF LO frequency to generate a GSM transmit RF information signal, and for upconverting the transmit IF information signal with a CDMA transmit RF LO frequency to generate at least one CDMA transmit RF information signal. The receiving unit comprises a downconverter for downconverting a CDMA receive RF information signal with a receive RF LO frequency to generate a receive IF information signal, and for downconverting at least one GSM receive RF information signal with the receive RF LO frequency to generate a receive IF information signal. It also includes a demodulator for demodulating the receive IF information signal with a receive IF LO frequency to generate a receive baseband information signal.