MODULATION AND DEMODULATION APPARATUS USING FREQUENCY SELECTIVE BASEBAND AND TRANSITION AND RECEPTION APPARATUS USING THE SAME

摘要

A modulator/demodulator using a baseband and a transmission/reception apparatus using the same without interference are provided to increase transmission data rate efficiently and improve a processing gain in an entire system. A spreader(218) in which a transfer data rate is improved includes an N bit counter, M bit data input bit, and a subtracter(2182). N bit counter outputs N bit input data. The subtracter selects the frequency band in which (N-M) bit frequency selection control bit and offset input bit are input and desiring. The logical multiplier of N is the output of N bit counter. The output bit of the first device operates sum of logic of (N-M) beat frequency selection control bit and (N-1) first logic multiplier. The second device for operating sum of logic performs an OR operation the output of the logical multiplier of N.