Determining signal channel impulse response using subcarrier pilot signals
US10050811B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 2014 |
| Grant date | Aug 14, 2018 |
| Priority date | — |
| Expiry date | Oct 3, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2665
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Distortion caused by spurious components in a determined channel impulse response (CIR) is reduced. In an OFDM (orthogonal frequency-division multiplexing) system pilot signals are applied to different subcarriers of different symbols in accordance with a pilot transmission scheme. Channel estimates are determined by time-interpolation for some of the data slots of the received signal which do not already include a pilot signal. For each of a sequence of symbols, a respective Inverse Fast Fourier Transform is performed on the pilot signals and interpolated channel estimates in the data slots of that symbol, thereby determining a sequence of estimated CIRs for the sequence of symbols. Spurious channel components will vary across the sequence of estimated CIRs, whereas the true channel peaks will tend not to significantly vary across the sequence of estimated CIRs. Therefore the sequence of estimated CIRs can be filtered (e.g. with a low-pass filter) to attenuate the spurious components, thereby determining a CIR for the signal for which the distortion caused by the spurious components is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.