| 摘要 |
PURPOSE:To attain the reception of incoming call and making a call to/from any place wherever and whenever the titled telephone set is carried even during walking on a street by providing a function receiving the (i+n)th kind of wide band call signal to a portable telephone set replying the i-th kind of exchange. CONSTITUTION:A function registering a home area where each of plural portable telephone sets 2 is normally located and designation information assigned to represent each telephone set 2 distinguishingly to the exchanges of the i-th kind and the (i+1)th kind is provided. Then the telephone set 2 is replied to a call from the i-th kind exchange to be registered. Moreover, in case of no reception at the registration, a function to receive the broad band call signal of the (i+n)th kind via the (i+n)th kind (n=1, 2...) of exchanges placed at the high-order hierarchy while operating a call bell section is provided. |
