System and method for synchronizing sample rates of voiceband channels and a DSL interface channel
View Patent ↗A system is provided for synchronizing a PSTN clock and a DSL clock. The system comprises a PSTN interface for transmitting and receiving voiceband samples, a data DSL transceiver for modulating and demodulating data to and from DSL samples, a synchronization circuit for synchronizing the voiceband samples and the data samples, and a converter for converting the synchronized voiceband and DSL samples between analog and digital formats. The synchronization circuit synchronizes the voiceband and the data samples for conversion by the same converter.
1. A system for synchronizing voice signal received via a public switched telephone network (PSTN) and data signal received via a digital subscriber line (DSL), the system comprising:
a PSTN interface coupled to transmit and receive the voice signal;
a data DSL transceiver coupled to modulate and demodulate the data signal;
a synchronization circuit coupled to synchronize said voice signal and said data signal; and
a converter circuit coupled to convert the synchronized voice signal and the synchronized data signal between analog and digital formats, wherein said synchronization circuit synchronizes said voice signal with said data signal, and comprises:
a phase offset detection circuit coupled to detect a phase difference between a PSTN clock associated with said voice signal and a DSL clock associated with said data signal;
a phase interpolation circuit coupled to adjust said voice signal according to the detected phase difference; and
a multiplexer circuit coupled to multiplex said data signal with the adjusted voice signal for transmission.
2. A system for synchronizing voice signal received via a public switched telephone network (PSTN) and data signal received via a digital subscriber line (DSL), the system comprising:
a PSTN interface coupled to transmit and receive the voice signal;
a data DSL transceiver coupled to modulate and demodulate the data signal;
a synchronization circuit coupled to synchronize said voice signal and said data signal; and
a converter circuit coupled to convert the synchronized voice signal and the synchronized data signal between analog and digital formats, wherein said synchronization circuit synchronizes said voice signal with said data signal and comprises:
a phase offset detection circuit coupled to detect a phase difference between a PSTN clock associated with said voice signal and a DSL clock associated with said data signal;
a demultiplexer circuit coupled to demultiplex said voice signal and said data signal from a received signal; and
a phase interpolation circuit coupled to adjust said voice signal according to the detected phase difference.
3. The system of claim 1 further comprising: circuitry adapted to combine the voice signal and the data signal.
4. The system of claim 3 further comprising: a converter circuit coupled to convert the combined voice and data signals between analog and digital formats.
5. The system of claim 2 further comprising: circuitry adapted to combine the voice signal and the data signal.
6. The system of claim 5 further comprising: a converter circuit coupled to convert the combined voice and data signals between analog and digital formats.