Patent ID: 7280468

Claim:
An apparatus for constant amplitude coded bi-orthogonal demodulation, comprising: a bi-orthogonal demodulation unit for demodulating received constant amplitude bi-orthogonal modulated data, canceling parity bits and then generating serial data; an error detector for detecting the occurrence of an error while dividing the data demodulated in the bi-orthogonal demodulator into a plurality of groups of data and then outputting the serial data of the bi-orthogonal demodulator as demodulated data if an error does not occur; an error bit polarity converter for sequentially converting bit polarities of data of groups with errors if the error detector detects the errors and converting the data of groups with errors and the data of groups with no errors into the serial data; a constant amplitude coded bi-orthogonal modulator for performing the constant amplitude coded bi-orthogonal modulation for the output data of the error bit polarity converter; a distance comparator for comparing bit-by-bit distances between the received bi-orthogonal modulated data and the constant amplitude coded bi-orthogonal modulated data of the constant amplitude coded bi-orthogonal modulator; and a buffer for storing a number of serial data output from the error bit polarity converter and selectively outputting the corresponding serial data as demodulated data according to a control signal of the distance comparator.