應用於77GHz汽車防撞雷達之13GHz訊號源設計

Abstract

本論文之內容為13GHz訊號源的設計還有其77GHz雷達模組的電源設計。前面先來談電源設計，由於77GHz雷達模組為多種電路所組成，其中包含收發機晶片、六倍頻器、頻率合成器，所以電源設計的目的在於整合各種偏壓，簡化電壓輸入的方式。設計上是用一個12V的直流電壓輸入電路板上各家廠商所製造的穩壓器來產生電路上所需要的各式偏壓，來讓77GHz雷達模組工作。 13GHz訊號源的設計架構是利用6.5GHz的壓控振盪器輸入倍頻器使其產生13GHz的訊號。其中6.5GHz的壓控振盪器是採用矽鍺高頻電晶體利用負電阻式振盪器的方式來設計，整體電路為一個共射極的架構，諧振電路放置在基極，改變電壓操控變容二極體控制調頻範圍，核心的主動元件電路為產生負電阻的特性，集極則為輸出端來輸出6.5GHz的訊號。最後結合場效應電晶體所設計的倍頻器來完成13GHz訊號源。

In this thesis, we design a 13GHz source for 77GHz radar transceiver application and a power board for 77GHz radar module. At first, we describe about the power board design rule. The 77GHz radar module is composed of many circuits, i.e. RF IC, frequency multiplier, and frequency synchronizer. They need different bias voltage to work. Intent to reduce different kinds of input voltage, we integrate all of them in one input voltage. Thus, the final voltage is 12V DC to supply regulators in PCB, which are manufactured by different IC corporations, like Richtek, Linear Technology, and Texas Instruments. Next, 13GHz source in this thesis, is made of a signal which is 6.5GHz VCO generate into frequency doubler to achieve. We use SiGe RF transistor and varactor to design VCO. It is designed by negative resistance oscillator and we use common emitter as its circuit structure. Placing the resonator at base, which is designed to control tuning range with varactor. Design transistor circuit to let it have negative resistance property. Collector is the output port to transmit the 6.5GHz signal. About the frequency doubler, we use FET and set its bias as class-A type to design it, which can reduce the circuit area. At last, combine 6.5GHz VCO and frequency doubler to achieve the 13GHz source.