Patent ID: 8571136

Claim:
A method of reducing interference in radio communications, comprising the steps of: providing at least two time domain orthogonal frequency-division multiplexing symbols; extending at least one time domain orthogonal frequency-division multiplexing symbol, wherein the step of extending comprises the steps of: identifying at least one licensed user radiowave frequency band, wherein the licensed user radiowave frequency band is examined for interference susceptibility; suppressing interference to the licensed user radiowave frequency band using an adaptive symbol transition unit, wherein the suppressing step comprises: selecting a symbol extension using a linear least squares with quadratic constraint of the at least one licensed user radiowave frequency band; appending the symbol extension onto the at least one time domain orthogonal frequency-division multiplexing symbol to form a cyclic prefix-extended orthogonal frequency-division multiplexing symbol; wherein the symbol extension is added as a cyclic prefix in a guard interval of the at least two time domain orthogonal frequency-division multiplexing symbols; wherein an extension value of the cyclic prefix is generated based on the licensed user location and bandwidth; and generating an orthogonal frequency-division multiplexing radiowave signal consisting of at least one of the cyclic prefix-extended orthogonal frequency-division multiplexing symbol.