Verification of PN synchronization in a direct-sequence spread-spectrum digital communications system
US6002709A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 4, 1998 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Sep 4, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/0334
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In a direct sequence spread spectrum digital communication receiver, a system and method for recovering and verifying the timing or phase of a pseudo-random noise (PN) sequence used for despreading received signals. In one embodiment, the method includes steps of: (a) determining an initial value of a received PN phase, (b) setting the receiver's PN phase equal to the initial value of the received PN phase, (c) a first testing to verify that the receiver identifies a SYNC field within a testing time of predetermined duration, (d) a second testing, to verify that temporarily shifting the receiver's PN phase results in a degraded correlation between the receiver's PN sequence and the received signal, and (e) repeating steps (a)-(d) if either of the testings indicate that the receiver's PN sequence is not correct. One embodiment of a system for recovering and verfying the PN timing includes an input for receiving a received spread-spectrum data stream, a maximal likelihood detection logic, a receiver PN clock, a despreading mixer that generates a narrowband signal from the spread-spectrum data stream, a first testing logic that generates a PASS output if it identifies a SYNC field in …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.