Correlating filter and CDMA receiver
US6148044A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1997 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Jan 14, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H21/0012
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A correlating filter includes a delay circuit which outputs a plurality of tap output signals TP1 to TPn having different delays. The correlating filter further includes a weighted adder circuit which weights the tap output signals, respectively, and adds the weighted tap output signals so as to derive a correlated output signal. A timing control circuit produces a control signal based on the correlated output signal from the weighted adder circuit. The control signal is high in level when the correlated output signal has a correlation peak. A power feed to the weighted adder circuit is achieved via a switching element. The switching element is only turned on when the control signal is high in level so as to enable the power feed to the weighted adder circuit. Thus, reduction in power consumption is achieved and the filter can be used in a portable radio device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.