| US 7,508,805 B2 | ||
| Apparatus and method for detecting transmitting rate of turbo decoder | ||
| Soon-Jae Choi, Songnam-shi (Korea, Republic of); Min-Goo Kim, Suwon-shi (Korea, Republic of); Beong-Jo Kim, Songnam-shi (Korea, Republic of); Young-Hwan Lee, Songnam-shi (Korea, Republic of); Nam-Yul Yu, Seoul (Korea, Republic of); and Sang-Hyuck Ha, Suwon-shi (Korea, Republic of) | ||
| Assigned to Samsung Electronics Co., Ltd., Suwon-Si (Korea, Republic of) | ||
| Appl. No. 10/398,369 PCT Filed Oct. 05, 2001, PCT No. PCT/KR01/01670 § 371(c)(1), (2), (4) Date Aug. 11, 2004, PCT Pub. No. WO02/29992, PCT Pub. Date Apr. 11, 2002. |
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| Prior Publication US 2005/0053040 A1, Mar. 10, 2005 | ||
| Int. Cl. H04B 7/216 (2006.01); H03M 13/00 (2006.01); H03M 13/03 (2006.01); H04L 25/34 (2006.01); H04L 25/49 (2006.01) | ||
| U.S. Cl. 370—342 [375/287; 714/758; 714/794; 714/786] | 13 Claims |
| 1. A method for decoding coded data in one frame transmitted from a transmitter at one data rate of a plurality of data rates
by a turbo decoder of a receiver having no information on a data rate at which the coded data is transmitted, and detecting
a data rate of the coded data, comprising the steps of:
(a) decoding the coded data in the frame at a selected data rate of the plurality of the data rates by the turbo decoder and
calculating a current decoding state value indicating an average of absolute values of log likelihood ratio (llr) values being
identical to decoded values of the coded data, output from the turbo decoder;
(b) calculating a current under-decoding state value defined as a difference between the current decoding state value and
a previous decoding state value;
(c) comparing the current decoding state value with a first threshold;
(c-1) performing CRC (Cyclic Redundancy Check) checking on the decoded data if the current decoding state value is larger
than a first threshold;
(c-2) comparing the current under-decoding state value with a second threshold if the current decoding state value is not
larger than a first threshold;
(c-3) performing CRC checking on the decoded data if the current under-decoding state value is larger than a second threshold;
and
(d) determining the selected data rate as a data rate of the coded data transmitted from the transmitter, if the CRC checking
result is good.
|