Apparatus and method for clock recovery in a communication syste

Details Apparatus and method for clock recovery in a communication syste Apparatus and method for clock recovery in a communication syste

1996-10-07

1999-04-27

Chin, Stephen

Pulse or digital communications

Synchronizers

Phase displacement, slip or jitter correction

376372, 376219, 370516, H03D 324, H04L 700

Patent

active

058987444

ABSTRACT:
A method for recovering the clock in an ADSL (asymmetric digital subscriber line) communication system at the receiver to match the frequency of the transmitted signal. A digital phase locked loop (DPLL) based clock is used to adjust the frequency of data read accesses from a FIFO (first-in first-out) memory (26) in a transceiver unit. The frequency is adjusted according to a predetermined offset value, where the offset value indicates the relative difference between a read location in the FIFO memory (26) and a write location. The predetermined offset value defines an operating point or nominal data location in the FIFO memory (26). A FIFO phase detector (31) determines and affects the frequency adjustment to maintain the FIFO memory at approximately the operating point. One embodiment provides clock recovery for a received ADSL subchannel and a means to recover a 16 kHz clock for a channel control.

REFERENCES:
patent: 5367545 (1994-11-01), Yamashita et al.
patent: 5402452 (1995-03-01), Powell et al.
patent: 5500874 (1996-03-01), Terrell
patent: 5548624 (1996-08-01), Yoshida
patent: 5596301 (1997-01-01), Rybicki et al.
Alliance for Telecommunications Industry Solutions, "Asymmetric Digital Subscriber Line (ADSL) Metallic Interface", Draft American National Standard for Telecommunications, Network and Customer Installation Interfaces, T1E1.4/94-007R7, pp. i-xii and p. 170.
J. Bellamy, "Digital Telephony", Second Edition; John Wiley & Sons, Inc., Section 7.1.1 through Figure 7.4. (1994).

Affiliated with

Also associated with

Rating

Apparatus and method for clock recovery in a communication syste does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus and method for clock recovery in a communication syste, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for clock recovery in a communication syste will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-690819