論文摘要 本論文主要敘述宇宙微波背景輻射陣列望遠鏡接收機之校準信號源系統的設計與測試。校準信號源架構主要可以分成兩個部份來說明。 第一部分製作可以遠端控制的YIG頻率合成器，它的控制範圍在21~26GHz，主要是由一台微型電腦來控制YIG頻率合成器產生21~26GHz信號，其YIG頻率合成器係由YIG振盪器串級、梳型振盪信號串級和鎖相迴路模組所組成。YIG振盪器串級由YIG振盪器發出信號接上隔離器和耦合器後輸出；梳型振盪信號串級利用100MHz當作信號源，串接鎖相同軸共振振盪器將信號鎖住在1GHz，輸入梳型產生器產生1GHz的諧波，再利用升頻混頻器，與信號產生器輸出的21GHz信號混頻 (未來由 AMiBA接收機中的鎖相介質共振振盪器信號源取代)，得到21~26GHz間隔1GHz信號輸出；鎖相迴路模組則是將YIG振盪器串級和梳型振盪信號串級所產生的信號，用降頻混頻器得到25MHz中頻訊號，並與另一參考信號源在鎖相電路模組中做頻率相位檢測比較，使其將YIG頻率合成器所產生信號鎖住。 第二個部分是將YIG頻率合成器信號做傳輸分路，用功率分配器分兩路徑各搭配一組機械控制的相移器，分別串接相同的切換器陣列做切換，切換後的輸出信號經過乘四倍頻器輸出至AMiBA的13個接收機當校準信號源。 本論文研製之校準信號源，目前已完成了YIG頻率合成器、相位調整和傳輸元件測試，未來將配合AMiBA接收機，完成接收機陣列的校準整合測試。 Abstract In this thesis, the design and test of calibration source for Array for Microwave Background Anisotropy(AMiBA) telescope receiver are proposed. The implementation of calibration source is separated into two sections. In the first section, the YIG synthesizer was designed. It could export signals about 21~ 26 GHz with interval of 1GHz, which is controlled by an embedded computer. The YIG synthesizer is composed of a YIG oscillator chain, comb generator chain and phase-locked circuit module. The output of YIG oscillator chain is generated by a YIG oscillator followed by an isolator and a coupler. The comb generator chain has a 100MHz crystal oscillator as reference source, which connects to a phase-locked coaxial resonator oscillator to generate 1GHz output signal. A comb generator is then used to generate harmonics of 1GHz, and then the harmonics are mixed with a 21GHz signal from the signal generator (In the future, it will replace by the output of phase-locked dielectric resonator oscillator from AMiBA receiver). The up-converted signal outputs will be 21~26GHz with 1GHz interval. The phase-locked circuit module is then used to integrate the YIG oscillator chain and comb generator chain into a phase-locked-loop. The phase-locked loop incorporates a down conversion mixer, and the outputs of YIG oscillator chain and comb generator chain are connected to the RF and LO port of the mixer. The 25MHz IF output is compared with the reference signal so as to lock the YIG synthesizer output frequency. In the section section, the output of YIG synthesizer is divided into two paths by a dual output amplifier and connected to two mechanical phase shifters which are followed by two switch array. The switched output signal is imported to a multiply-by-4 harmonic generator, and then transmitted to the 13 receivers of AMiBA as a calibration source. In this thesis, we have completed the implementation of the YIG synthesizer and most part of the transmission components. The testing and integration of proposed calibration source with the AMiBA receiver array will be done in the near future.
