Simple encoding/decoding technique for code position modulation
US6594317B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2002 |
| Grant date | Jul 15, 2003 |
| Priority date | — |
| Expiry date | Apr 8, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L23/02
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for encoding and decoding signals using code position modulation (CPM) in a communication system. The encoding method includes storing an N-chip pseudo-random noise sequence, such as an m-sequence, in a circular shift register and circularly shifting it to obtain a shifted m-sequence. The shifted m-sequence is compared to an m-bit symbol corresponding to the k bit information value. If the shifted m-sequence and the m-symbol match, the shifted m-sequence is output as the N-chip CPM sequence. Alternatively, the m-symbol is used as an initial condition for a pseudo-noise sequence generator. The corresponding decoder stores an N-chip m-sequence in a circular shift register and a correlates shifted version of the m-sequence with a received N-chip CPM sequence. When a peak in the correlation value is detected, an m-bit field is retrieved from the circular shift register and mapped back to a k-bit information value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.