Splitter for analog telephone signal and digital data

A central office installation for transmitting and receiving frequency multiplexed analog telephone signals and digital data signals over a line, wherein the installation comprises:

• a splitter for demultiplexing and multiplexing analog telephone signals and digital data signals,
• a digital data signals device connected to the splitter for transmitting and receiving digital data signals, and
• an analog telephone signals device connected to the splitter for transmitting and receiving analog data signals, wherein the analog telephone signals device generates a standard POTS ringing signal when a ringing indication signal is detected, the ringing indication signal having a voltage amplitude less than 30 V RMS and comprising a spectrum that lacks detectable components in a frequency band that is used for digital data signals at a time when the ringing indication signal announces an incoming telephone call.

A splitter for transmitting and receiving frequency multiplexed analog telephone signals and digital data signals over a line port, said splitter comprising:

• means for demultiplexing and multiplexing analog telephone signals and digital data signals,
• a telephone port for transmitting and receiving analog telephone signals to and from said demultiplexing and multiplexing means, and
• ringing signal generation means for generating a ringing signal applied to the telephone port when a ringing indication signal is received over said line port, wherein the ringing indication signal has a voltage amplitude less than 30 V RMS and a spectrum that lacks detectable components in a frequency band for digital data signals at a time when the ringing indication signal announces an incoming telephone call.

A central office installation for transmitting and receiving frequency multiplexed analog telephone signals and digital data signals over a line, wherein the installation comprises:

• a splitter for demultiplexing and multiplexing analog telephone signals and digital data signals,
• a digital data signals device connected to the splitter for transmitting and receiving digital data signals, and
• an analog telephone signals device connected to the splitter for transmitting and receiving analog data signals, wherein the analog telephone signals device transmits a ringing indication signal for announcing an incoming telephone call, the ringing indication signal having a voltage amplitude less than 30 V RMS, wherein the analog telephone signals device transmits a ringing signal for announcing an incoming telephone call when the digital data signals device does not receive digital data signals and the ringing signal has a voltage amplitude higher than the ringing indication signal.