OFDM channel estimation and tracking for multiple transmit antennas
US7539259B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 28, 2004 |
| Grant date | May 26, 2009 |
| Priority date | — |
| Expiry date | Mar 24, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2647
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Multiple Transmit Multiple Receive Orthogonal Frequency Division Multiplexing (‘OFDM’) comprising generating bit streams and corresponding sets of N frequency domain carrier amplitudes ({tilde over (s)}(kN+j), 0≦j≦N−1) modulated as OFDM symbols subsequently to be transmitted from a transmitter, where k is the OFDM symbol number and j indicates the corresponding OFDM carrier number. Affix information is inserted at the transmitter into guard intervals between consecutive time domain OFDM symbols and are used at the receiver to estimate the Channel Impulse Response (Hlm) of the transmission channels, the estimated Channel Impulse Response (Ĥlm) being used to demodulate the bit streams in the signals received at the receiver. The affix information is known to the receiver, as well as to the transmitter, and is mathematically equivalent to a vector (cD) that is common to the time domain OFDM symbols multiplied by at least first weighting factors (αk) that are different for one time domain OFDM symbol (k) than for another and second weighting factors (wi(k)) that enable one of the transmit antenna means (i) to be distinguished from another.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.