Interference suppression in DS-CDMA systems
US5790537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1996 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | May 15, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/7107
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A code division multiple access (CDMA) communications system comprises a plurality of CDMA transmitters and at least one reception station coupled together by a communications channel. Each CDMA transmitter encodes a digital signal with a spreading code, each bit of the digital signal being encoded by a spreading code segment comprising a multiplicity of chips. All of the transmitters transmit their respective encoded signals to the reception station asynchronously via the communications channel so as to occupy the same bandwidth. Each receiver receives the combined signals of all of the transmitters and correlates it with a selected one of the spreading code segments to detect the digital signal from the corresponding transmitter. Each receiver uses also the signal-to-noise ratios of detected signals other than its own, with respect to chip delays relative to a reference one of the signals, to suppress multiple access interference (MAI) caused by such other detected signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.