EXCHANGE INTERFACE DEVICE FOR A WIRELESS LOCAL LOOP, ESPECIALLY WITH REGARDS TO CONFIGURING A PCM(PULSE CODE MODULATED) DTMF MEMORY, WHILE SUPPLYING A PCM DTMF INPUT SIGNAL

摘要

PURPOSE: An exchange interface device for a WLL(Wireless Local Loop) is provided to add a DTMF memory for supplying a PCM(Pulse Code Modulated) DTMF control signal corresponding to a DTMF control signal, and to supply the DTMF input signal to a CEPT framer, thereby assigning the PCM DTMF input signal to plural channels with one memory. CONSTITUTION: A DTMF memory(14) stores a PCM DTMF input signal corresponding to a DTMF control signal. A controller(13) controls reframing or framing operations of a CEPT reframer(11) and a CEPT framer(12) by receiving the DTMF control signal, and reads the DTMF input signal stored in the DTMF memory(14), then transmits the read DTMF input signal to the CEPT framer(12). The CEPT framer(12) channelizes digitally PCM dialing numbers to transmit the channelized dialing numbers. The digital PCM data is switched in a time switch, and is outputted as a signal again. The outputted PCM data is changed into an analog DTMF signal by a PCM decoder(16), and is outputted to an exchange.