Patent Document ID: 20090180557
Application ID: 12007821
Patent Flag: 0

Claim One:
1. An orthogonal frequency division multiplexing (OFDM) system for transmitting a modulated subcarrier signal from a transmitting end, transforming a frequency domain signal into a time domain signal via an inverse fast fouier transform, inserting a guard interval between two time domain signals and transforming a time domain signal from parallel data into serial data, transmitting the signal from the transmitter via a wireless channel to a receiver, the receiver transforming serial data into parallel data and removing the guard interval, utilizing a fast fouier transform process to transform the time domain signal into a frequency domain signal to provide a received signal, using an equalizer to obtain an original received signal, and restore beck to the original two digits information output via signal inverse correspondence, characterized in that: error detection is performed on the received signal obtained from the fast fouier transform process to detect whether the received subcarrier has any errors, and the channel estimator obtains a frequency response of the channel by controlling the error detection.