Method of demodulation in digital communication systems with multipath propagation
US5029186A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1989 |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | Jan 13, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2338
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method of demodulation in digital communication systems with multipath propagation, based on the use of algorithms of the Viterbi, Fano, Stack and similar types, with soft decision type decoding, where there is included calculation of reference values in the receiver, and the receiver in its selection of received sequence takes as a basis a calculation of metrics using the difference between possible transmitted sequences and the signal received, and where the receiver only processes sequences having each a limited number of consecutive data symbols which in the following are denoted "known" and the instantaneous value of the received signal is influenced by a number of data symbols being larger than the number of "known" symbols, other data symbols being in the following denoted "unknown" data symbols, and the receiver employs an estimate of the impulse response (h(t)) of the multipath propagation channel, is characterized in that the calculation of the reference values for a certain sequence of "known" data symbols includes obtaining a transmitted signal for a sequence of data symbols having a length equal to the sum of the "known" and one or more "unknown" data symbols, formin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.