| 摘要 |
An additional device for a cordless telephone set, including: a communication unit that makes radio communication with a main device; a communication control unit that decides a radio channel for communication available to transmit and receive a signal to or from the main device; a display unit that displays information; a signal strength detection unit that periodically detects a signal strength of a radio signal received from the main device by the communication unit; a signal strength estimation unit that estimates a current signal strength of the radio signal from the main device, based on plural signal strengths acquired before; and a display control unit that displays a communication status with the main device on the display unit, based on the signal strength estimated by the signal strength estimation unit. |
