Method, interface modules and telephone network for multiplexing and demultiplexing an analog MTS (message telephone service) signal and an ADSL (asymmetric digital subscriber line) datastream

Claim 2

A method according to claim 1, characterized in that , in case a failure occurs in said first step, said second step, said third step or said fourth step, telephone service is maintained by transporting said analog MTS (Message Telephone Service) signal (TS) in its analog form to and from said transmission line (TL) respectively via independent link lines (L, L').

Claim 3

A method according to claim 1, characterized in that in said multiplexing, said first step comprises a first substep wherein said analog MTS (Message Telephone Service) signal (TS) is fractionized into said analog speech (AS) and said telephone service signalling (TSS), a second substep wherein said analog speech (AS) is converted into digital speech (DS), and a third substep wherein said telephone service signalling (TSS) is encoded into a telephone service code (TSC), said digital speech (DS) and said telephone service code (TSC) both forming part of said digital MTS (Message Telephone Service) signal (DS, TSC), and furthermore that in said demultiplexing, said fourth step comprises a fourth substep wherein said telephone service code (TSC) is decoded into said telephone service signalling (TSS), a fifth substep wherein said digital speech (DS) is converted into said analog speech (AS), and a sixth substep wherein said analog speech (AS) and said telephone service signal (TSS) are combined, thereby obtaining said analog MTS (Message Telephone Service) signal (TS).

Claim 4

A method according to claim 1, characterized in that in said multiplexing, said second step is performed by modulating said digital MTS (Message Telephone Service) signal (DS, TSC) on a subset of carriers which form part of a set of carriers whereon said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) is modulated to form said transmit signal (S), and that in said demultiplexing, said third step is performed by demodulating said digital MTS (Message Telephone Service) signal (DS, TSC) from said subset of carriers, whilst said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) is demodulated from other carriers comprised in said set of carriers.

Claim 5

A method according to claim 1, characterized in that in said multiplexing, said second step comprises a substep wherein said digital MTS (Message Telephone Service) signal (DS, TSC) is packed into ATM (Asynchronous Transfer Mode) cells, and an additional substep wherein said ATM (Asynchronous Transfer Mode) cells are embedded in said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) thereby generating said transmit signal (S), and furthermore that in said demultiplexing, said third step comprises an inverse substep wherein said ATM (Asynchronous Transfer Mode) cells are regenerated from said transmit signal (S), and an additional inverse substep wherein said ATM (Asynchronous Transfer Mode) cells are unpacked into said digital MTS (Message Telephone Service) signal (DS, TSC).

Claim 6

An interface module (CO-IM, S-IM) adapted to multiplex an analog MTS (Message Telephone Service) signal (TS), comprising analog speech (AS) as well as telephone service signalling (TSS), and an ADSL (Asymmetric Digital Subscriber Line) datastream (AD) to be simultaneously applied to a two-wire transmission line (TL) coupled to said interface module (CO-IM, S-IM), characterized in that said interface module (CO-IM, S-IM) includes a fractionizing unit (F), to an input of which said analog MTS (Message Telephone Service) signal (TS) is applied and which is adapted to fractionize said analog MTS( Message Telephone Service) signal (TS) to thereby generate said analog speech (AS) applied to a first output (FO1) thereof and said telephone service signalling (TSS) applied to a second output (FO2) thereof, an analog to digital converter (ADC), whose input is coupled to said first output (FO1) of said fractionizing unit (F) and which is provided to convert said analog speech (AS) into digital speech (DS), an encoder (E) coupled at its input to said second output (FO2) of said fractionizing unit (F) and provided to encode said telephone service signalling (TSS) into a telephone service code (TSC), and a multiplexer (MUX) to first (MI1), second (MI2) and third (MI3) inputs of which said digital speech (DS), said telephone service code (TSC) and said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) are supplied respectively and which is provided to embed said digital speech (DS) and said telephone service code (TSC), which both form part of a digital MTS (Message Telephone Service) signal (DS, TSC), in frames comprised in said ADSL (Asymmetric Digital Subscriber Line) datastream (AD).

Claim 7

An interface module (CO-IM, S-IM) according to claim 6, characterized in that said interface module (CO-IM, S-IM) further includes first switching means (S1) with at least a first state output (1) connected to said input of said fractionizing unit (F) and a second state output (2) connected to a first end of an independent link line (L), and to an input of which said analog MTS (Message Telephone Service) signal (TS) is applied, and second switching means (S2) with at least a first state input (1') connected to an output of said multiplexer (MUX) and a second state input (2') connected to a second end of said independent link line (L) and an output of which is coupled to said two-wire transmission line (TL), in such a way that when said first and second switching means (S1, S2) are brought in their second state, said analog MTS (Message Telephone Service) signal (TS) is applied in its analog form to said two-wire transmission line (TL) via the cascade connection of said first switching means (S1), said link line (L), and said second switching means (S2).

Claim 8

An interface module (CO-IM, S-IM) adapted to demultiplex an analog MTS (Message Telephone Service) signal (TS), comprising analog speech (AS) as well as telephone service signalling (TSS), and an ADSL (Asymmetric Digital Subscriber Line) datastream (AD) from a transmit signal (S) applied to said interface module (CO-IM, S-IM) via a transmission line (TL) coupled to said interface module (CO-IM, S-IM), characterized in that said interface module (CO-IM, S-IM) includes a demultiplexer (DEMUX) whose input is coupled to said transmission line (TL) and which is adapted to demultiplex said transmit signal (S) and to thereby generate digital speech (DS), a telephone service code (TSC) and said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) for application to a first (DO1), a second (DO2) and a third (DO3) output of said demultiplexer (DEMUX) respectively, a digital to analog converter (DAC) coupled at its input to said first output (DO1) of said demultiplexer (DEMUX) and provided to convert said digital speech (DS) into said analog speech (AS), a decoder (D) coupled at its input to said second output (DO2) of said demultiplexer (DEMUX) and provided to decode said telephone service code (TSC) and to thereby generate said telephone service signalling (TSS), and a combining unit (C), a first input (CI1) of which is coupled to an output of said digital to analog converter (DAC) and a second input (CI2) of which is coupled to an output of said decoder (D) and which is provided to combine said analog speech (AS) and said telephone service signalling (TSS) into said analog MTS (Message Telephone Service) signal (TS) and to apply said analog MTS (Message Telephone Service) signal (TS) to an MTS output of said interface module (CO-IM, S-IM).

Claim 9

An interface module (CO-IM, S-IM) according to claim 8, characterized in that said interface module (CO-IM, S-IM) further includes first switching means (S1') with at least a first state input (1'') connected to said output of said combining unit (C) and a second state input (2'') connected to a first end of an independent link line (L'), and whose output is connected to said MTS output, and second switching means (S2') with at least a first state output (1''') connected to an input of said demultiplexer (DEMUX) and a second state output (2''') connected to a second end of said independent link line (L'), and to an input of which said transmit signal (S) is applied by said two-wire transmission line (TL), in such a way that when said first and second switching means (S1', S2') are brought in their second state, said transmit signal (S) is transported to said MTS output via the cascade connection of said second switching means (S2') said link line (L') and said first switching means (S1').

Claim 10

Telephone network including a central office station and a plurality of subscriber stations coupled to said central office station via transmission lines (TL), said central office station and said subscriber stations including interface modules (CO-IM, S-IM) provided to multiplex and demultiplex an analog MTS (Message Telephone Service) signal (TS), comprising analog speech as well as telephone service signalling, and an ADSL (Asymmetric Digital Subscriber Line) datastream (AD) for simultaneous transmission thereof over a said two-wire transmission line (TL), characterized in that to perform said multiplexing, a said interface module (CO-IM, S-IM) in said central office station and in each said subscriber station includes a fractionizing unit (F), to an input of which said analog MTS (Message Telephone Service) signal (TS) is applied and which is provided to fractionize said analog MTS( Message Telephone Service) signal (TS) to thereby generate said analog speech (AS) applied to a first output (FO1) thereof and said telephone service signalling (TSS) applied to a second output (FO2) thereof, an analog to digital converter (ADC), whose input is coupled to said first output (FO1) of said fractionizing unit (F) and which is provided to convert said analog speech (AS) into digital speech (DS), an encoder (E) coupled at its input to said second output (FO2) of said fractionizing unit (F) and provided to encode said telephone service signalling (TSS) into a telephone service code (TSC), and a multiplexer (MUX) to first (MI1), second (MI2) and third (MI3) inputs of which said digital speech (DS), said telephone service code (TSC) and said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) are supplied respectively and which is provided to embed said digital speech (DS) and said telephone service code (TSC), which both form part of a digital MTS (Message Telephone Service) signal (DS, TSC), in frames out of said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) to thereby constitute a transmit signal (S), and that to perform said demultiplexing, a said interface module (CO-IM, S-IM) in said central office station and in each said subscriber station includes a demultiplexer (DEMUX) whose input is coupled to said two-wire transmission line (TL) and which is provided to demultiplex said transmit signal (S) and to thereby regenerate said digital speech (DS), said telephone service code (TSC) and said ADSL (Asymmetric Digital Subscriber Line) datastream (AD) applied to a first (DO1), a second (DO2) and a third (DO3) output of said demultiplexer (DEMUX) respectively, a digital to analog converter (DAC) coupled at its input to said first output (DO1) of said demultiplexer (DEMUX) and provided to convert said digital speech (DS) into said analog speech (AS), a decoder (D) coupled at its input to said second output (DO2) of said demultiplexer (DEMUX) and provided to decode said telephone service code (TSC) and to thereby regenerate said telephone service signalling (TSS), and a combining unit (C), a first input (CI1) of which is coupled to an output of said digital to analog converter (DAC) and a second input (CI2) of which is coupled to an output of said decoder (D) and which is provided to combine said analog speech (AS) and said telephone service signalling (TSS) into said analog MTS (Message Telephone Service) signal (TS) and to apply said analog MTS (Message Telephone Service) signal (TS) to an MTS output of said interface module (CO-IM, S-IM).