5G通訊Ka頻段相位偵測電路及K頻段發射功率偵測電路

Abstract

本論文主要研究為通訊及相位陣列天線系統上所需的偵測電路，操作頻段為K與Ka頻段，應用於發射端即時功率偵測與波束成型所需的相位偵測。本論文首先回顧功率偵測器與相位偵側器等相關電路文獻，並介紹其運作原理、電路架構及應用目的。於第一個電路中，我們採用共源極功率偵測器搭配低耦合係數之堆疊變壓器式方向耦合器，降低對輸出功率的影響並採用成對的架構來降低功率偵測器對溫度的變異，實際量測可得在K頻段操作下，於輸出功率為0 dBm時最小輸出電壓為43.1 mV，於Psat為16.3 dBm時最大輸出電壓為1.205 V，從0 dBm至OP1dB操作範圍內線性度誤差小於±1 dB，直流功耗為 98 μW。於第二個電路中，使用45˚延遲傳輸線搭配低耦合係數之耦合線方向耦合器實現全相角相位可偵測的相位偵測器，實際量測可得在Ka頻段操作下，於輸入功率為3 dBm時最大輸出電壓為81.2 mV，且在0˚~360˚相位差下兩弦波形式的輸出電壓相為差100.68˚而設計理想值為90˚，經由數學計算後可得最大相位差計算誤差為 -28˚與18.8˚兩種。

This thesis studies detectors which operate in K-band, and Ka-band for wireless communications and phased array antenna systems.First, a K-band PA transmitted power detector using the common-source structure with a low coupling factor stacked directional coupler is presented. In order to decrease effects of temperature, the power detector is realized in pairs and one of the pair is a reference source. The measured minimum voltage is 43.1 mV at 0 dBm, and maximum voltage is 1.205V at Psat at 16.3 dBm, The linearity error from 0 dBm to Psat is under ±1 dB. The quiescent DC power is 98 μW.Second, a Ka-band 0˚ ~360˚ phase detector using 45˚ transmission line and a low coupling factor coupled line directional coupler is presented. The measured minimum voltage is 81.2 mV at 3 dBm, and phase difference between two sinusoidal output voltages is 100.68˚ where designed phase difference is 90˚, after mathematical calculation, the maximum phase error are -28˚, 18.8˚.