Abstract:
A constant amplitude coded bi-orthogonal demodulator demodulates the received constant amplitude bi-orthogonal modulated data, cancels the parity bits to generate the serial data, detects the occurrence of an error by dividing the demodulated data into a plurality of groups of data, outputs the serial data as demodulated data if an error does not occur, sequentially converts bit polarities of data of groups in which an error occurs if the error detector detects the error, compares distances between the received bi-orthogonal modulated data and the constant amplitude coded bi-orthogonal modulated data, and selects, as demodulated data, data of which corresponding bit polarities are changed according to the comparison results. According to the present invention, power consumption is reduced, a power amplifier can be manufactured at an inexpensive cost, interference robustness can be ensured, and data can be transmitted at a high transmission rate and a variable transmission rate.
Abstract:
An apparatus for transmitting data in a wireless communication system is disclosed. An apparatus for transmitting data in a wireless communication system according to the present invention includes a serial to parallel converter operable to transform serial data into parallel data; a summer operable to combine the parallel data after multiplying them by orthogonal code; a level clipper operable to remove a portion of the summed signal above and below a desired threshold range; and a quadrature phase shift keying(QPSK) modulator operable to change the phase of the clipped signal and to transfer the modulated signal therefrom. Thus, the present invention can embody high-speed data transfer rate in such a simple structure by combining a VSG method with an MC method to clip multi-level signals from the MC method and to maintain orthogonality of MC required in the VSG method.