	US 7,415,090 B2
	Method and device for loop timing recovery based on maximum constellation signal
Jun-young Jeong, Suwon-si (Korea, Republic of)
Assigned to Samsung Electronics Co., Ltd., (Korea, Republic of)
Filed on Jan. 26, 2005, as Appl. No. 11/43,470.
Claims priority of application No. 10-2004-0006596 (KR), filed on Feb. 02, 2004.
Prior Publication US 2005/0169394 A1, Aug. 04, 2005
Int. Cl. H04L 7/00 (2006.01); H04L 27/06 (2006.01)

U.S. Cl. 375—355 [375/340]

19 Claims

1. A method of performing loop timing recovery of received data in a multiple channel communications system, the method comprising:

selecting at least one channel among a plurality of channels in the multiple channel communications system on which the received data signals are largely unaffected by noise by detecting channel noise among the received data signals;

selecting at least one channel among the plurality of channels on which the received data signals have a magnitude greater than a predetermined magnitude among the received data;

folding the received data signals of the selected at least one channels onto a 1^stquadrant of a quadrature amplitude modulation (QAM) coordinate plane;

rotating and mapping the folded received data signals of the selected at least one channels onto a Real=Imaginary axis;

shifting the rotated received data signals to a reference constellation having predetermined value; and

unfolding the shifted received data signals onto 2^nd, 3^rd, and 4^thquadrants of the QAM coordinate plane to coincide with a 4-QAM format.