| 摘要 |
PROBLEM TO BE SOLVED: To provide a public base station system of a simple type portable telephone which can give advantages to a offerer of base station installation place in addition for maximal utilization of an information channel of a public digital communication line (Γ-line) for contracted simple portable telephone. SOLUTION: A transmissive interface part A9 of a public radio base station A performs transmission of a speech communication signal, the feeding to a telephone system B, direct current closure detection, sending and receiving of a DTMF signal, receiving of a dial pulse signal, polarity inversion, generation of a 16Hz calling signal, and generation of an outgoing tone/calling middle tone/speech middle tone, etc. A public line termination part A10 terminates a public digital telephone line, such as the Γ-line and an ISDN line, and performs data communication processing of a round signal, a control signal, etc. |
