HIGH FREQUENCY UNIT INCLUDING BASE BAND USING SINGLE CLOCK

摘要

PURPOSE: A high frequency unit including a base band using a single clock is provided to simplify a reference clock signal used for a high frequency unit and a base band chip as one clock signal for thereby simplifying a system and implement a system at a lower cost. CONSTITUTION: A data receiver receives high frequency data from an antenna(10) and converts into a base band signal having a certain frequency and outputs as an audio signal through a speaker(40). A data transmitter converts audio data inputted through a microphone(50) into a high frequency signal and transmits through the antenna(10). The data receiver includes a low noise amplifier(LNA)(61) for receiving a signal from the antenna(10) and amplifying the signal. A first mixer(62) receives an oscillation from the first voltage control oscillator(63) and the amplified receiving signal, and outputs a signal of 10.7MHz. A crystal oscillator(66) generates a reference clock frequency of 11.15MHz. A PLL(65) operates in synchronization with the reference clock frequency from the crystal oscillator(66). A base band receiver operates based on the reference clock signal from the PLL(65) and converts the signal from the first mixer(62) into a base band signal and outputs to the speaker(40).