利用陶瓷封裝電晶體設計20GHz介質振盪器之研究

Abstract

在高頻下, 由於電路的寄生效應很複雜,所以振盪器一般來說,是採用 S參數直接設計, 而負阻抗產生的基本原因沒有辦法直接判斷.在本篇 論文中,將利用適當的電晶體(HEMT) 等效模型來分析六種回授組態的 負阻抗產生.在這個分析中,可以預測產生負阻抗的頻率 範圍.由以上 分析的結果,應用於設計20GHz介質振盪器和YIG振盪器.20GHz介質振盪器 由 封裝電晶體實現,而以上的設計是著眼在低成本的製成.振盪器的實 驗量測結果:平均輸出 功率為-18dBm,相位雜訊-70dBc/Hz At high frequency, oscillator is normally designed from [S] parameters because of complicated parasitic. While the basic origins of existing negative resistance can not be easily figured out. In this study, the negative resistance of six configurations are examined by appropriate model of HEMT. The frequency ranges of existing negative resistance are predicted. The results are applied to a 20GHz DRO as well as a YIG oscillator. 20GHz DRO is realized directly by the packaged active device and 20GHz DR from the view point of low cost fabrication. The DRO with reasonable performances of output power of -18 dBm and -70dBc/Hz phase noise at 100KHz offset is obtained.