Delta modulation for channel feedback in transmit diversity wireless communication systems
US7376192B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 2004 |
| Grant date | May 20, 2008 |
| Priority date | — |
| Expiry date | May 24, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03802
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method is described herein for reducing the number of feedback bits needed to send channel state information over a feedback channel from a receiving unit (e.g., mobile terminal, base station) to a transmitter unit (e.g., base station, mobile terminal) in a wireless communication system. In the embodiment, the receiver unit is capable of performing the following steps: (1) receiving a pilot signal from a transmit antenna located at a transmitter unit; (2) analyzing a channel tap associated with the transmit antenna and exploiting the temporal correlations of the channel tap to generate the following (i) a delta-modulated feedback bit indicative of a real part of a complex coefficient of the channel tap associated with the transmit antenna and (ii) a delta-modulated feedback bit indicative of an imaginary part of the complex coefficient of the channel tap associated with the transmit antenna; and (3) sending the two feedback bits over a feedback channel to the transmitter unit which analyzes the two feedback bits, and other feedback bits corresponding to other channel taps of this and other transmit antennas, to optimize the subsequent transmission of data to the receiver unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.