(54) MULTI-STAGE RECEIVER
(75) Inventors: Bin Li, Ottawa (CA); Wen Tong, Ottawa (CA)
(73) Assignee: Nortel Networks Limited, St-Laurent (CA)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
(21) Appl. No.: 10/435,799
(22) Filed: May 12, 2003
Related U.S. Application Data
(63) Continuation of application No. 09/311,708, filed on May 13, 1999, now Pat. No. 6,587,517, which is a continuationin-part of application No. 09/220,014, filed on Dec. 23, 1998, now Pat. No. 6,526,103.
(51) Int. C I. I103K 9 00
(52) U.S. CI 375/316; 375/347
(58) Field of Search 375/316, 346,
375/347, 349, 340, 130; 370/342, 335, 329, 331; 714/794, 780; 455/132, 137,
246.1
(56) References Cited
U.S. PATENT DOCUMENTS
5,329,547 A * 7/1994 Ling 370/342
Primary Examiner—Khai Tran
(57) ABSTRACT
A multi-stage receiver and method for recovering a traffic signal embedded in at least one received signal. The multistage receiver includes a plurality of sequential detection stages for processing each received signal and providing successively better estimates of the traffic signal. The multistage receiver includes, for each received signal, a first processing stage and a second processing stage. The multistage receiver also includes a final processing stage connected to the second processing stages. Each first processing stage generates a first estimate of the traffic signal from the respective received signal and each second processing stage generates a set of energy values from the respective first estimate of the traffic signal and from the respective received signal. The final processing stage combines the set of energy values from each second processing stage and generates an improved estimate of the traffic signal. By employing multiple stages in the receiver, there is an improvement in successive estimates of the traffic signal.
7 Claims, 13 Drawing Sheets
