IDLE CHANNEL DETECTION METHOD

摘要

PURPOSE:To utilize a radio wave effectively by allowing a transmission station to send a signal at a lower level than usual to an object channel and allowing an opposite reception station to receive the signal and to measure the line quality thereby deciding an available idle channel. CONSTITUTION:A base station 2 sends a transmission signal 4 at a lower level than that of a transmission power to a channel location considered to be an idle channel. A mobile equipment 1 receives the mixture of the low level signal 4 sent from the base station 2 and an interference signal 5 from a 3rd station 3. The mobile equipment 1 uses a channel selection circuit 6 to select a channel and a signal appearing at an idle channel location is demodulated by a demodulation circuit 8. Then an error symbol of the demodulated signal is detected and a level ratio of the interference signal 5 from the 3rd station 3 and the transmission signal 4, is detected by a level detection circuit 7. Thus, the interference quantity is estimated with high accuracy and the radio wave is effectively utilized in the mobile communication processed in a minimum zone.