Method and apparatus for adaptive linear equalization for walsh covered modulation
US6522683B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 2000 |
| Grant date | Feb 18, 2003 |
| Priority date | — |
| Expiry date | May 6, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03477
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A receive filter receives signals from a communication channel. The received signals correspond to original Walsh covered chip sequences transmitted by a transmit filter through the communication channel to the receive filter. The received signals are processed by an equalizer to generate a soft estimate of chip sequences corresponding to the original Walsh covered chip sequences. An N chip Walsh decover is then utilized to generate a soft estimate of code symbols corresponding to the soft estimate of the chip sequences. A number of symbol slicers are then used in parallel to produce a hard estimate of the code symbols corresponding to the soft estimate of code symbols generated by the N chip Walsh decover. Thereafter an N chip Walsh cover is used as part of a scheme to generate a hard estimate of chip sequences corresponding to the hard estimate of the code symbols generated by the symbol slicers. The hard estimate of the chip sequences generated with the aid of the N chip Walsh cover, and the soft estimate of the chip sequences generated by the equalizer, are used to generate a tracking mode error signal to adapt the response of the equalizer to the received signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.