Abstract: A wireless telecommunications system architecture is disclosed that is capable of supporting a centralized block radio architecture and of distributing the information-bearing signals from the block radio to geographically-dispersed radio heads using relatively low-cost cable (e.g., twisted-pair, etc.). In accordance with the illustrative embodiment of the present invention, a radio multiplexes, modulates, and channel codes one or more information-bearing signals and upconverts them, not to radio frequency, but to an intermediate frequency that can be transmitted over a low-cost cable. Co-located with each radio head is an upconverter that upconverts the intermediate frequency signal to radio frequency in preparation for radiation by an antenna.

Abstract: A wireless base station has a transmitter and receiver. Transmission signals are applied to an antenna through a transmit bandpass filter that is tuned for a transmit band of frequencies. Received signals from the antenna are applied to the receiver through a receive bandpass filter that is tuned for a receive band of frequencies. An RF switching array consisting of four RF switches interconnects the output of the transmitter and the input of the receiver such that normal, loopback (self-test), and scanning modes can be performed. In the normal mode, the antenna is connected to the transmitter and receiver through the transmit and receive bandpass filters, respectively. The transmit and signal paths are effectively isolated from each other by three serially-connected open switches. In the loopback mode, the transmitter output is connected to the receiver input. In the scanning mode, the antenna is connected to the receiver through the transmit bandpass filter.