C波段低相噪频率源的设计

介绍基于DRO（Dielectric Resonator Oscillator）技术的低相噪微波频率源,由于DRO的高Q值其相比于锁相环（PLL）技术具有更低的相位噪声,用低温度系数的介质谐振器,有效地改善了振荡器的频率温度稳定性.同时减小介质谐振器与微带线之间的耦合度,能进一步改善相位噪声.论文设计的输出频率为4GHz的DRO在频偏10KHz处相位噪声-122dBc/Hz,输出功率8.5dBm,二次谐波抑制-42dBc,证明了其在低相位噪声频率源应用上的优势.

Design of C-band Frequency Source with Low Phase Noise

Theory and technique of DRO（Dielectric resonator oscillator） in designing microwave frequency source with low phase noise are introduced in this paper. It has much lower phase noise compared with phase-locked loop（PLL） since DRO has high Q value, and effectively improves the temperature stability of the oscillator frequency in using dielectric re- sonator with low temperature coefficient, and reduces the coupling coefficient between the microstrip line and dielectric re- sonator to further improv phase noise. A 4GHz DRO is designed. Simulation results reveal that the phase noise is --122dBc/ Hz at 10KHz offset frequency, output power is 8. 5dBm, second harmonic suppression is --42dBc. The outcome verifies the DRO＇s advantage in frequency source with low phase noise application.