| Summary: | 碩士 === 國立中正大學 === 電機工程所 === 94 === This thesis aim is to design an ultra-wideband CMOS RF receiver front-end using standard 0.18um CMOS process. There are several RF components which include ultra-wideband low-noise amplifier, ultra-wideband down-conversion mixer, ultra-wideband voltage-controlled oscillators. In first components, we adopt the modified source L-degenerate technology and cascade structure in the design of ultra-wideband low-noise amplifier. Besides, we also designed an negative shunt feedback structure to improve frequency response. This structure can sense the output voltage and feed back a current signal to improve bandwidth. In addition, feedback structure provides a low input impedance, generating a 50-Ω real part for proper matching. Therefore, the narrowband frequency response can be converted into a new wideband function by the design of feedback structure. The addition of negative shunt feedback increase a little power consumption and gain loss . In second components, we use the LC ladder matching networks to achieve broadband in the design of ultra-wideband down-conversion mixer. Because the output port of LNA is single ended , a single ended input and double balanced mixer is also desirable. The mixer is based on the Gilbert transconductance multiplier cell. In third components, we employ the cross-coupled structure to design voltage-controlled oscillators. Besides, we also designed an even harmonic mixer to achieve broadband result by mixing the input signal with the even harmonic of the second input signal. In this paper, the design and analysis will be discussed in detail, respectively. Based on measured results, they will reveal the designed circuits can be fit the requirement of UWB receiver.
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