Signal processing circuit for spread spectrum communications
US5488629A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1994 |
| Grant date | Jan 30, 1996 |
| Priority date | — |
| Expiry date | Feb 17, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J13/10
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A signal processing circuit provided with a frequency conversion circuit for converting a spread quadrature modulation signal of a carrier band into a baseband signal, a first correlator, a second correlator, a third correlator, a fourth correlator spreading code, a decoding circuit for decoding data from outputs of the first to fourth correlators, a first multiplier for calculating the square of the output of the first correlator, a second multiplier for calculating the square of the output of the second correlator, a first adder for adding up outputs of the first and second multipliers, a judgment circuit for performing a synchronization acquisition judgement, a second adder for adding up the outputs of the first and second correlators, or those of the first and fourth correlators, a subtracter for performing a subtraction between the outputs of the second and third correlators and a correction circuit for obtaining a frequency offset according to an output of the second adder and/or that of the subtracter and performing a correction when decoding the data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.