System and method for communicating data using symbol-based randomized orthogonal frequency division multiplexing (OFDM) with selected subcarriers turned on or off
US7813433B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 16, 2006 |
| Grant date | Oct 12, 2010 |
| Priority date | — |
| Expiry date | May 9, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/0044
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A device and system communicates data and includes a modulation and mapping circuit that modulates and maps data symbols into a plurality of multiple subcarrier frequencies that are orthogonal to each other to form an Orthogonal Frequency Division Multiplexed (OFDM) communications signal based on a fixed or variable OFDM symbol rate. A pseudo-random signal generator is operative with the modulation and mapping circuit and generates pseudo-random signals to the modulation and mapping circuit based on an encryption algorithm for frequency hopping each subcarrier at an OFDM symbol rate to lower any probability of interception and detection, reduce power per frequency (dB/Hz/sec), and lower any required transmission power while maintaining an instantaneous signal-to-noise ratio, wherein selected subcarriers are turned ON or OFF to increase the transmit power and signal-to-noise ratio and reduce the Inter-Carrier Interference (ICI) and adverse effects of frequency selective fading.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.