Method and system for sample and recreation synchronization for digital transmission of analog modem signal

• US 7,130,337 B2
• Filed: 07/02/2001
• Issued: 10/31/2006
• Est. Priority Date: 07/02/2001
• Status: Active Grant

• Current Assignee: Gula Consulting Limited Liability Company (Intellectual Ventures LLC)
• Original Assignee: Phonex Broadband
• Inventors: Hoobler, Ryan
• Primary Examiner(s): Fan, Chieh M.
• Assistant Examiner(s): PUENTE, EVA YI ZHENG
• Application Number:
  US09/898,295
• Publication Number:
  US 20030002572A1
• Time in Patent Office: 1,947 Days
• Field of Search: 375/222, 375/229, 375/267, 375/373, 375/251, 375/377, 375/216, 370/294, 370/493, 455/402, 455/557
• US Class Current: 375/222
• CPC Class Codes: H04L 7/0008 Synchronisation information channels, e.g. clock distribution lines
• CPC Class Codes: H04L 7/044 using a single bit, e.g. start stop bit

Abstract

A method and system for the synchronization of the transmission of digitally converted analog modem signals between two or more modems using either RF over-the-air or A/C power line communication channels. This invention provides for modem speed optimization my minimizing or eliminating clock variance between the modems in a digital communication system. A fixed delay is created and maintained during modem operation. This invention is also adapted to function in a full-duplex communication system maintaining a fixed delay in both directions.

Claims

1. A method of synchronizing a digital transmission of analog modem signals, comprising:

receiving, at a second modem, a first digital data signal from a first modem via a transmission medium, wherein;

said first digital data signal is received serially, and

said first digital data signal comprises a first sample clock signal, said first sample clock signal comprising a first start bit representing a delay;

detecting said first start bit by said second modem;

generating, by said second modem, a first recreation clock signal based on said first start bit, wherein said first recreation clock signal comprises said delay;

converting said first digital data signal to a first analog signal by a first digital-to-analog converter;

generating, by said second modem, a second analog signal, said second analog signal comprises a second sample clock signal, said second sample clock signal comprising a second start bit;

converting, by a first analog-to-digital converter, said second analog signal to a second digital data signal; and

transmitting, by said second modem, said second digital data signal to said first modem via said transmission medium.

2. A method of synchronizing the digital transmission of analog signals, as recited in claim 1, wherein said transmission medium is an A/C power line.

3. A method of synchronizing the digital transmission of analog signals, as recited in claim 1, wherein said transmission medium is an over the air RF signal.

4. A method of synchronizing a digital transmission of analog signals, as recited in claim 1, further comprising:

receiving, at said first modem, said second digital data signal from said second modem;

detecting said second start bit by said first modem;

generating, by said first modem, a second recreation clock signal based on said second start bit, wherein said second recreation clock signal comprises said delay;

converting said second digital data signal to a third analog signal by a second digital-to-analog converter;

generating, by said first modem, a fourth analog signal said fourth analog signal comprises a first sample clock signal, said first sample clock signal comprising said first start bit;

converting, by a second analog-to-digital converter, said fourth analog signal to a said first digital data signal; and

transmitting, by said first modem, said first digital data signal to said second modem via said transmission medium.