Path searched device and CDMA receiver with the same
US6487193B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 1999 |
| Grant date | Nov 26, 2002 |
| Priority date | — |
| Expiry date | Aug 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/18584
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention is directed to a path searching device and a CDMA receiver employing the same, having a reduced circuit scale and operating to carry out a smaller number of operations. For a direct spreading CDMA communication system, a CDMA receiver includes a reception demodulator including an antenna, a high-frequency amplifier a band-pass filter, demodulators, etc. The CDMA receiver also has despreading units, a determination unit, and a path search device. The path search device has a sampling unit for sampling an input signal by low-speed oversampling based on an integer multiple of a chip rate and by high-speed oversampling that is faster than the low-speed oversampling, a first circuit for finding a correlative value between a spreading code and a signal provided by the low-speed oversampling and finding timing corresponding to a maximum correlative value. A second circuit for finding despreading timing according to correlative values between a signal provided by the high-speed oversampling and a spreading code corresponding to the timing provided by the first circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.