Method and device for sensing frequency for OFDM systems

摘要

Provided is a frequency sensing method and apparatus in an orthogonal frequency division multiplexing (OFDM) system. Provided is a method of sensing a frequency of a received signal that is received from an outside in order to perform one of a plurality of radio communications. An OFDM apparatus may need to inspect a required frequency band before or after performing one of the plurality of radio communications, and to determine whether the frequency band is being used by another radio communication.

主权项

1. A method of sensing a frequency in an orthogonal frequency division multiplexing (OFDM) system, the method comprising:
dividing a frequency band of a received signal into a plurality of first subchannels through a first fast Fourier transform (FFT); detecting one subchannel including a valid signal from the divided plurality of first subchannels; outputting a filter coefficient corresponding to the frequency band of the detected subchannel; filtering the received signal according to the frequency band of the detected subchannel, to obtain a band-pass-filtered received signal, based on the filter coefficient; dividing the frequency band of the band-pass-filtered received signal into a plurality of second subchannels through a second FFT; and detecting another subchannel including the valid signal from the divided plurality of second subchannels of the band-pass-filtered received signal.