【摘要】 在DRM DAB系统设计中,压控振荡器需要满足宽的调频范围,而其压控增益的差别需要控制在一定的范围内,以使得锁相环的稳定性得到提高,同时为了降低锁相环环路对噪声的敏感性,我们需要低的压控增益。据此,本文所采用的可变电容阵列结构有效地满足了上述要求,使用SMIC 0.18μm CMOS工艺,仿真得到的结果显示在1.71G振荡频率1MHZ频偏处的相位噪声为-124.3d Bc/Hz.压控范围为1.71-2.31GHz。更多还原

【Abstract】 In the design of DRM/DAB system, the voltage- controlled oscillator(VCO)needs to have a large frequency tuning range. Its gain variation should be keeped in a small range,in order to make the PLL more stable. Also, to make the PLL less sensitive to the noise, we need to achieve a low VCO gain. The variable varactors structure adopted in this paper can meet the requirements above. Using SMIC 0.18-μm CMOS process. The simulation results show the phase noise is- 124.3 d Bc/Hz at 1-MHz frequency offset at 1.71-GHz oscillation frequency, the tuning range is from 1.71 to 2.31 GHz.更多还原