| 摘要 |
PURPOSE:To surely detect a weak carrier at multi-channel access by setting a line reference signal level lower with respect to a level of a reference signal at the outside of a talking zone. CONSTITUTION:A control circuit 9 retrieves sequentially an idle channel from a 10-th channel (CH). Supposing that other cordless telephone set uses the 10CH, the carrier of the CH is received by a radio transmission reception section 5 and a level detection section 71 of a detection circuit 7 detects a level of a reception signal V0 and a comparator section 75 compares the level of a line reference signal V2 with the level of the signal V0. Even when the level of the signal V0 is lower than the level of a reference signal V1 at the outside of a communication zone and when the level of the signal V0 is higher than the level of the channel connection reference signal V2, the comparator section 75 does not provide a detection signal of an H level indicating an idle CH. Thus, the control circuit 98 does not discriminate the 10CH to be an idle CH and the retrieval transits to a succeeding 9CH. When an idle CH is detected, it is stored in a storage area of the control circuit 9. A radio channel is connected between a master set and a slave set by the stored CH at the time of channel connection. |
