Methods and apparatus for synchronously combining signals from plural transmitters
US7218682B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 2002 |
| Grant date | May 15, 2007 |
| Priority date | — |
| Expiry date | Feb 26, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/026
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Enhanced reception of transmitted signals in a communication system is achieved by synchronously combining transmissions from a cluster of transmitters at a distant receiver. The transmitters coordinate transmissions such that each substantially simultaneously transmits the same signal on the same communication channel. As a consequence of the spatial diversity of the transmitters, the transmitted signals arrive at the receiver at different times. The receiver essentially treats the different transmitted signals as though they were different multipath signals from a single transmitter. A multipath equalizer or combiner is used to determine timing offsets among the received signals, and the received signals are time aligned by phase rotating the signals in accordance with the estimated timing offsets. The time-aligned signals are then coherently combined and detected. The combined signal has a greater signal-to-noise ratio than the individual received signals, permitting detection at a greater range or with a lower bit error rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.