Systems and methods for extracting coherent correlation data
US7185038B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 2003 |
| Grant date | Feb 27, 2007 |
| Priority date | — |
| Expiry date | Aug 18, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/4818
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method allow receivers to quickly acquire a pseudorandom noise signal. A receiver advantageously detects frequency shifts using a compact parallel process hardware implementation of a Discrete Fourier Transform (DFT). The simultaneous detection of multiple frequencies allows the receiver to search the frequency range of the transmitted signal in larger increments of frequency, thereby increasing the speed of acquisition. One receiver does not use coherent integration before computation of the transform and advantageously maintains a flat frequency response. The flat frequency response of the DFT circuit enables searching of multiple frequency offsets without CPU intensive processing to compensate for frequency response variations. A receiver can include a Doppler correction circuit, which permits correlation data with frequency shift in the code to be non-coherently integrated among relatively fewer addresses or tap positions in memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.