| 摘要 |
PURPOSE:To clearly identify whether the error is due to a cause outside the service zone or due to interference by another system by judging a telephone call circuit state based on the comparison between the number of slot errors and average values of received levels in the measurement block. CONSTITUTION:An antenna 31 of a master set B receives a transmission signal S10 from an antenna 11 of a slave set main body A, and a radio communication circuit 32 converts the signal into a base band signal S14 and it is given to a reception data processing section 34. Then the processing section 34 gives a control signal S14 to a control section 38 and gives digital audio signal 16 to an ADPCM section 35. Then an error discrimination section 39 discriminates a status of a telephone line based on the comparison between a slot error number and a received average level for a measurement block to discriminate the error. The status is fed to the control section 38, which gives each information to an error data processing section 41 and a level data processing section 42, in which the information is processed internally. Thus, the control section 38 identifies whether the occurrence of error is due to a cause at the outside of the service zone or due to interference by other system. |
