The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 02, 1993
Filed:
Feb. 07, 1991
Telefonaktiebolaget L M Ericsson, Stockholm, SE;
Abstract
Signals in synchronizing sequences and data sequences are transmitted over a fading channel to a Viterbi-receiver. The signals are received by antennas and sampled to received antenna signals (s.sub.in,r (k)). Part channel estimates (h.sub.est,r) for the individual antennas are formed. For Viterbi-analysis, assumed input signals (s.sub.a,r (.DELTA.T.sub.ij,k)) for the data sequence are produced with the aid of the part channel estimates (h.sub.est,r). Part metric values (m.sub.r (.DELTA.T.sub.ij, k)) are formed as a difference between the received antenna signal (s, .sub.in,r (k)) and corresponding assumed input signals (s.sub.a,r (.DELTA.T.sub.ij, k)) for Viterbi state transitions (.DELTA.T.sub.ij). For one state transition there is formed a metric value such as the sum of a metric value ((M(T.sub.j, k-1)) for an old state (T.sub.j) at a preceding sampling time point (k-1) increased with a weighted (K.sub.r) sum of the part metric values (m.sub.r (.DELTA.T.sub.ij, k)) belonging to individual part channel estimates (h.sub.est,r). Corresponding metric values are formed for all state transitions to the new state (T.sub.i) and the smallest of these metric values is chosen in accordance with the Viterbi-algorithm.