本論文以智慧型天線系統之波束成型模組(Beam-forming module)與訊號來向(Direction of Array, DOA)偵測器中的關鍵被動組件為設計目標。首先，因應第五代行動通訊發展需求，本論文題出操作於28 GHz頻段之切換式波束成型晶片，設計上使用橋式T線圈取代傳輸線以縮小4×4巴特勒矩陣的電路尺寸，進而與吸收式單刀四擲開關整合成切換式波束成型晶片，並實現於砷化鎵製程中。整體晶片尺寸僅1.798 mm×1.85 mm，在28 GHz的電氣尺寸為0.172 λ0 ×0.168 λ0。其次，因應多頻、多模的操作需求，採用雙頻橋式T線圈實現微型化雙頻六埠網路設計，以做為訊號來向偵測器的基本組件。此雙頻六埠網路的操作頻率為2.45與5.8 GHz，並實現於積體被動電路(IPD)製程中，電路面積僅5.85 mm×5.47 mm，在2.45 GHz的操作頻率下電氣尺寸為0.0477 λ0 ×0.0446 λ0，在5.8 GHz的頻率下電氣尺寸則為0.113 λ0 ×0.105 λ0。;In this thesis, a compact switched beamformer for use in a beam-forming antenna array and a dual-band six-port network for use in a direction of arrival estimator are proposed, which will serve as key passive building block designs of a smart antenna system. First, the design of an on-chip switched beamforming network is demonstrated at 28 GHz, which is based on the integration of an absorptive single-pole four-throw (SP4T) switch and a 4×4 Butler matrix using the GaAs pHEMT process. A compact circuit size is achieved by using bridged-T coils to replace transmission line sections in the 4×4 Butler matrix. Specifically, the circuit size is only 1.798 mm×1.85 mm while the electrical size is around 0.172 λ0×0.168 λ0 at 28 GHz. Driven by the demand of multi-frequency and multi-mode wireless communication apparatus, a dual-band six-port network is also developed, in which dual-band bridged-T coils are employed as the buildings blocks. The two operating frequencies of the dual-band six-port network are set as 2.45 and 5.8 GHz, and it is implemented using an integrated passive circuit (IPD) process. The circuit size is only 5.85 mm×5.47 mm. The corresponding electrical size is around 0.0477 λ0× 0.0446 λ0 at 2.4 GHz and 0.113 λ0×0.105 λ0 at 5.8 GHz.
