Orthogonal frequency division multiplexing (OFDM) communications device and method that incorporates low PAPR preamble and variable number of OFDM subcarriers
US8175178B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 2008 |
| Grant date | May 8, 2012 |
| Priority date | — |
| Expiry date | Jan 31, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/262
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A communications device includes communications data and a training sequence corresponding to a preamble. A modulation and mapping circuit modulates the communications data and training sequence into a plurality of multiple subcarriers that are orthogonal to each other to form an OFDM communication signal having modulated subcarriers carrying the communications data forming a data payload and modulated subcarriers forming the preamble. A circuit turns OFF and ON selected subcarriers based on an encryption algorithm to increase transmit power and signal-to-noise ratio and reduce the Inter-Carrier Interference (ICI). The modulation and mapping circuit applies a quadratic modulation to the subcarriers carrying the training sequences to produce a low peak-to-average power ratio (PAPR) preamble with a PAPR value of approximately 2.6 decibels (dB).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.