US 7,463,707 B2
Upstream frequency control for docsis based satellite systems
Mark Dale, Laguna Hills, Calif. (US); Dorothy D. Lin, Laguna Beach, Calif. (US); Alan Gin, Corona Del Mar, Calif. (US); David L. Hartman, Laguna Hills, Calif. (US); Rocco J. Brescia, Jr., Newport Coast, Calif. (US); Ravi Bhaskaran, Irvine, Calif. (US); Jen-chieh Chien, Lake Forest, Calif. (US); and Adel Fanous, Irvine, Calif. (US)
Assigned to Broadcom Corporation, Irvine, Calif. (US)
Filed on Jan. 28, 2003, as Appl. No. 10/352,244.
Claims priority of provisional application 60/407308, filed on Sep. 03, 2002.
Prior Publication US 2004/0042574 A1, Mar. 04, 2004
Int. Cl. H04L 7/00 (2006.01); H03D 3/24 (2006.01)
U.S. Cl. 375—356  [375/373] 22 Claims
OG exemplary drawing
 
1. A method for minimizing frequency error of a satellite modem at a satellite gateway, comprising:
(a) downconverting by said satellite modem a downstream signal using a first oscillator;
(b) recovering by said satellite modem a downstream symbol rate from said downstream signal;
(c) enabling said satellite modem to lock a satellite modem's master oscillator to said downstream symbol rate;
(d) locking elements controlling upstream frequency to said satellite modem's master oscillator;
(e) sending upstream satellite frequency offset information from said satellite gateway to said satellite modem; and
(f) enabling said satellite modem to calculate an upstream frequency offset based upon said upstream satellite frequency offset information, wherein said upstream satellite frequency offset is compensated for by shifting a center frequency for said satellite modem's master oscillator,
wherein said first oscillator is not locked to said satellite modem's master oscillator, whereby frequency offsets introduced during said step (a) do not change said downstream symbol rate.