本篇論文提出一個5 GHz頻率調變連續波(Frequency-Modulated Con-tinuous Wave)訊號產生器。所提出之電路主要目標為在低中心頻率時產生更大的頻率調變範圍(Modulation Range),如此能在相同調變範圍下大幅降低功耗。採用以小數型鎖相迴路(Fractional-N Phase-locked Loop)為主的頻率合成器作為訊號產生器,此頻率合成器能以5 GHz為中心頻率調變700MHz(13.6%)的頻率範圍。一可變換極性之三階鎖相迴路(Type-3 PLL)被應用在本架構中,可有效改善在頻率轉折點和頻帶切換點的線性度。除此之外三階的架構亦可打破迴路頻寬對調變速度的限制。本論文提出透過切換頻帶控制電路(Switching Band Control circuit)和多組可變電容之LC壓控振盪器(Multi-varactor LC Voltage Control Oscillator)的組合來有效地提高輸出頻率的調變範圍,使頻率調變連續波雷達在距離的量測上能達到更高的準確度。本架構以台積電四十奈米互補式金氧半製程實現,所提出的頻率調變連續波訊號產生器總面積為1.96平方毫米而功耗則為3.2毫瓦。在鎖相迴路模式以5GHz為中心頻率,在相對於主頻率1 MHz的位置下所量測到的相位雜訊為-110 dBc/Hz。在頻率調變連續波模式以2.3 ms為週期調變700MHz的頻率下量測到的頻率誤差方均根值為625 kHz。
This thesis presents a 5-GHz frequency-modulated continuous wave sig-nal generator(FMCW). The presented circuit aims to generate a wider fre-quency modulation range at low center frequency that grants significant ad-vantage at saving power. Utilizing a fractional-N phase-locked loop (PLL)-based synthesizer as the FMCW generator, the synthesizer modulates thecarrier frequency across a range of 700 MHz(13.6%). A Type-3 architec-ture with a switchable polarity is embedded to improve the linearity aroundthe chirp turning-around points (TAPs) and switching-bands points (SAPs).Moreover, Type-3 architecture break the trade-off between modulation slopeand PLL loop bandwidth. Switching Band Control (SBC) circuit and Multi-varactorLCVoltageControlOscillator(MV-VCO)areproposedasaefficientmethod to increase the modulation range so that the FMCW signal generatorcan achieve high resolution in distance detecting.FabricatedinTSMC40-nm1P10MCMOStechnology, theproposedsig-nal generator consume 3.2 mW power and occupies1.96mm2die area. Themeasured phase noise from 5 GHz carrier is -110 dBc/Hz at 1 MHz offset.Themeasuredroot-mean-square(rms)frequencyerrorofthegeneratedtrian-gle chirp over 1.15 ms period is 625 kHz.