TRANSMITTER USING FREQUENCY HOPPING/CDMA

摘要

PURPOSE: A frequency hopping/CDMA(Code Division Multiple Access) with a direct digital synthesizer and a phase locked loop mixed is provided to obtain a fast setting time and a linear modulation. CONSTITUTION: A direct digital synthesizer(210) mixes and outputs a input signal and a frequency hopping sine wave modulated according to a frequency hopping pattern. A band pass filter(240) filters a signal output from the direct digital synthesizer at predetermined band width and generates a reference signal. A phase locked loop(220) multiplies the reference signal and converts into a desired frequency band. Thereby, it is possible to obtain a very precise resolution, a faster frequency modulation time and a excellent spurious characteristic by providing the frequency hopping/CDMA transmitter having the fast setting time and the linear modulation.