使用旋轉單元電場向量法進行相位陣列天線系統校正

Abstract

目前第五代行動通訊正在逐漸的成熟，而相位陣列天線是重要技術之一，為了達到系統的最佳化，需使用校正方法修正陣列中各路徑的差異，讓整個系統的能夠提升傳輸能量，或是增加傳輸的距離。 本論文在電磁模擬採取的架構分別為線性1×4相位陣列天線和線性1×8相位陣列天線，都是使用旋轉單元電場向量法進行相位補償，讓相鄰的天線單元之間沒有相位誤差，進而讓發射天線設置同相饋入時在波束成形θ=0°的位置能夠輻射最大的功率，且在反相饋入時在波束成形θ=0°的方向能夠輻射最小的功率。接者本論文再提出在不同波束成形的方向使用同樣的校正步驟，計算出不同波束成形方向時相鄰天線之間的相位誤差，再由已知的各個不同波束成形位置的相位誤差，透過內插法推算出陣列天線可視區域內每一個角度，波束成形在任意角度所需要的補償的相位，達到陣列天線在可視區域內都能夠輻射最大的功率，進而運用在現代的5G基地台天線，可讓使用者在任意的位置都能收到訊號。 量測方面分別使用雄才大略計畫的38GHz毫米波頻段1*8相位陣列天線波束成形的系統和捷豹公司的60GHz頻段2*4相位陣列天線波束成形的系統，利用第一個1*8相位陣列天線波束成形的系統，來驗證在相位補償後波束成形θ=0°的方向相鄰天線的相位差為0°，使得陣列天線能夠輻射最大功率。接著量測第二個2*4相位陣列天線波束成形的系統，來檢測波束成形在θ=-10°~10°任意一個方向皆能輻射最大功率。根據量測的結果可以知道本論文提出的校正步驟可以讓陣列天線在可視區域內的波束成形皆能輻射最大功率。

The fifth generation of mobile communications is gradually mature. Phased array is an important part in millimeter wave communication. The calibration of the array system is required to improve the power transmission of the entire system. In the simulation, we use a linear 1×4 phase array and a linear 1×8 phase array as examples, to test the rotating element electric field vector (REV) method for phase compensation. After the calibration, the transmitting antenna can radiate the maximum power at the beamforming direction θ = 0° when the array antenna fed in phase, and can radiate the minimum power at the beamforming direction θ = 0° when the array antenna fed in reversed phase. Then the same calibration steps are used at different beamforming direction to calculate the phase error between adjacent antennas, and then use the phase error which is known in specific beamforming positions, to calculate the compensation phase at any other beamforming direction in the visible area of the array antenna by interpolation. In the measurement verification, we use a 38GHz millimeter wave 1*8 phase array antenna beamforming system and the 60GHz band 2*4 phase array antenna beamforming system. First, we use the 1*8 phase array antenna to verify EIRP of adjacent antennas after the phase compensation. The phase array antenna can radiate maximum power. Second, we use a 2*4 phase array. According to the measurement results, the calibration steps proposed in this thesis can allow the array antenna to radiate the maximum power in the visible range.