US 7,321,780 B2 | ||
Enhanced uplink rate selection by a communication device during soft handoff | ||
Robert T. Love, Barrington, Ill. (US); Amativa Ghosh, Buffalo Grove, Ill. (US); Ravi Kuchibhotla, Gurnee, Ill. (US); and Nicholas W. Whinnett, Marlborough (United Kingdom) | ||
Assigned to Motorola, Inc., Schaumburg, Ill. (US) | ||
Filed on Apr. 30, 2003, as Appl. No. 10/427,361. | ||
Prior Publication US 2004/0219920 A1, Nov. 04, 2004 | ||
Int. Cl. H04M 1/00 (2006.01); H04Q 7/20 (2006.01) |
U.S. Cl. 455—522 [455/442] | 2 Claims |
1. A method for rate selection by a communication device for uplink during soft handoff in a communication system, the method
comprising steps of:
receiving a scheduling assignment message including a power margin limit from a scheduler;
determining a data rate for an uplink transmission during soft handoff using the power margin limit, local channel conditions
and a buffer occupancy of the communication device; and
transmitting to a serving base station on an uplink channel at the data rate determined from the determining step;
wherein the determining step includes a data rate constraint of
K2*Pmargin—limit/Pdpcch*TPC_correction
where Pmargin—limit is the power margin limit, Pdpcch is a power of the downlink physical control channel, and K2 is a scale factor, and TPC_correction dependent upon a power control
command history and pilot channel signal strength.
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