一种双带宽UHF主从耦合式LC VCO

为了满足无线通信系统应用需要,设计了一种主从耦合式LC压控振荡器(VCO).基于0.18 μm CMOS标准工艺,由一个5 GHz主VCO和两个起分频作用的从VCO组成,其中主VCO选用PMOS考毕兹差分振荡结构,在两个互补交叉耦合的从VCO的输出端之间设置有注入式NMOS器件以达到分频的目的.仿真及硬件电路实验结果表明,在1.8 V低电源电压下,5 GHz主VCO的调谐范围为4.68～5.76 GHz,2.5 GHz从VCO的调谐范围为2.32～2.84 GHz;在1 MHz的偏频下,5 GHz主VCO的相位噪声为118.2 dBc/Hz,2.5 GHz从VCO的相位噪声为124.4 dBc/Hz.另外,主从VCO的功耗分别为6.8 mW和7.9 mW,因此特别适用于低功耗、超高频短距离无线通信系统中.

UHF Master-Slave Coupled LC VCO with Two Bandwidthes

To meet the needs of wireless communication system, a master-slave coupled VCO was designed. The VCO based on 0.18 μm CMOS standardized technology is composed of a master 5 GHz VCO and two slave VCOs as the frequency divider. A full PMOS Colpitts differential oscillator structure was adopted on the master VCO. To achieve the function of dividing frequency, an injection NMOS was added between the two coupled slave VCOs. The simulation and hardware experimental results show that when the supply voltage is as low as 1.8 V, the turning ranges of the 5 GHz master VCO and 2.5 GHz slave VCO are from 4.68 to 5.76 GHz and from 2.32 to 2.84 GHz, respectively. When the offset frequency is 1 MHz, the measured phase noise of the master VCO is 118.2 dBc/Hz, while the measured phase noise of the slave VCO worked as divider is 124.4 dBc/Hz. The power consumption is 6.8 mW and 7.9 mW at master and slave VCO, respectively. So it is very suitable for low power and UHF communication systems.