首页>
外国专利>
Direct digital frequency synthesizer and a hybrid frequency synthesizer combining a direct digital frequency synthesizer and a phase locked loop
Direct digital frequency synthesizer and a hybrid frequency synthesizer combining a direct digital frequency synthesizer and a phase locked loop
展开▼
机译:直接数字频率合成器和结合了直接数字频率合成器和锁相环的混合频率合成器
展开▼
页面导航
摘要
著录项
相似文献
摘要
A direct digital frequency synthesizer and a hybrid frequency synthesizer combining the direct digital frequency synthesizer and a phase locked loop is provided. The direct digital frequency synthesizer includes a phase accumulator that is configured to generate a discrete phase signal. Spurious phase modulation in the discrete phase signal is reduced by a noise shaper, and the output of the noise shaper is then used to address a phase-to-amplitude translator. The phase-to-amplitude translator generates a discrete waveform which is converted to a continuous waveform by a digital to analog converter. The hybrid frequency synthesizer uses a mixer to combine a reference frequency generated by a reference source and a DDFS output signal generated by a direct digital frequency synthesizer. The output from the mixer is then coupled to the input of a phase locked loop which multiplies the mixer output to generate the frequency synthesizer output.
展开▼