Adaptive frequency planning in a cellular network

Radio frequencies of a base station in a cellular network are chosen adaptively so that when choosing the uplink frequency the base station measure at all frequencies or at some frequencies of the reception band used in the system what is the total power of the signal received at the frequency in question. The frequency at which the lowest power is received is chosen as uplink frequency. When choosing the downlink frequency, a tuning signal is transmitted at all frequencies or at some frequencies of the transmission band. Mobiles located in areas of other cells and operating at the same frequency experience the effect of the tuning signal as an interference. The base station is tuned to use that downlink frequency at which the interference caused by itself to other traffic is sufficiently low.