Apparatus for and method of minimizing backoff for orthogonal frequency division multiplexing transmission
US8189456B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2007 |
| Grant date | May 29, 2012 |
| Priority date | — |
| Expiry date | Nov 26, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/80
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A novel and useful mechanism for reducing the required backoff and the peak to average power ratio (PAPR) needed for an OFDM transmitter whiles still meeting spectral mask and EVM specifications. The mechanism searches, for each packet to be transmitted, for several possible scrambler and encryption sequences that would yield the best spectral mask and EVM with lowest PAPR. The search can be performed using the existing transmitter and receiver PHY circuit chain to modulate and demodulate the candidate hypotheses. Once the scrambler sequence and/or encryption sequence is selected, the packet is transmitted using the selected scrambler and encryption sequences. In addition, the invention exploits the fact that even for very low backoff margins, a reduced number of candidate hypotheses may be tested while still yielding a high probability of meet the spectral mask and EVM specifications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.