Apparatus and method for measuring sub-carrier frequencies and sub-carrier frequency offsets
US6757344B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 2002 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Nov 16, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0051
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Systems and methods are provided for identifying frequency offsets which may for example have been introduced after a signal has been transmitted over a wireless channel. The method involves sampling a received signal having an input bandwidth to generate a respective set of samples for each of a plurality of symbol periods; filtering the sets of samples using DWPT (discrete wavelet packet transform) filters to produce a plurality of sub-sampled outputs, the sub-sampled outputs each having a respective fraction of the input bandwidth; for each of the sub-sampled outputs, performing a narrowband FFT on the sub-sampled output produced over a plurality of symbol periods to generate a respective set of frequency domain samples; processing each set of frequency domain samples to determine at least one respective frequency offset.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.