Methods and apparatus for transmitting data over a CDMA network
US7085307B2 · kind B2 · utility
2Cited by
4References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Aug 1, 2006 |
| Priority date | — |
| Expiry date | Feb 16, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J2013/0037
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The use of cyclic prefixes with OFDM transmissions is known. Typically the prefix length is chosen to be at least as long as the duration of significant multipath in the transmission channel. However, OFDM has disadvantages in terms of DSP load and transmitter power amplifier specifications. The use of a cyclic prefix with periodic CDMA codes has been found to yield equivalent performance in terms of orthogonality in a dispersive channel and yet overcomes the disadvantages of cyclicly prefixed OFDM transmissions. Examples are given of Walsh Hadamard binary periodic codes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.