應用於第五代行動通訊毫米波系統之相位陣列系統與接收機電路元件之研製

Implementations of Phased Array System and Receiver Components for the 5G Millimeter Wave System

陳俊年(Chun Nien Chen)

指導教授 ： 王暉

國立臺灣大學/電機資訊學院/電信工程學研究所/博士(2020年)

https://doi.org/10.6342/NTU202003883

摘要

本論文之研究主題為應用於第五代行動通訊毫米波系統之相位陣列系統與接收機電路元件之研製。本論文之內容主要分為三個部分。
本論文之第一部分的研究為38-GHz毫米波相位陣列發射機與接收機系統的研製。毫米波晶片設計的部分，以65奈米互補式金屬氧化物半導體製程 (65-nm CMOS) 實現發射機與接收機波束成型電路晶片，以及升頻與降頻電路晶片；以0.15微米砷化鎵假晶高電子遷移率電晶體半導體製程 (0.15-μm GaAs pHEMT) 實現功率放大器與低雜訊放大器晶片。毫米波系統整合部分，以設計完成的毫米波晶片以及邊緣輻射毫米波天線整合於RO4003高頻印刷電路板 (print circuit board, PCB) 上，實現八路相位陣列發射機以及四路相位陣列接收機子系統模組。並利用此發射機與接收機子系統模組，以垂直疊合的方式實現三十二路相位陣列發射機系統以及十六路相位陣列接收機系統。根據發射機與接收機系統在38-GHz的量測結果，此三十二路相位陣列發射機系統在輸出功率1-dB功率壓縮點 (OP1dB) 的等效全向輻射功率 (equivalent isotropic radiated power, EIRP) 為47.5 dBm；十六路相位陣列接收機系統的輸出功率1-dB功率壓縮點為-4 dBm。此發射機與接收機系統皆支援水平方向 (azimuth) ±60°與垂直方向 (elevation) ±30°的波束掃描。將此發射機與接收機系統進行四象限振幅調變(quadrature amplitude modulation, QAM) 載波無線對傳測試，於20公尺的傳輸距離可實現 64 QAM/400 M-BR (2.4 Gbps)，256 QAM/200 M-BR (1.6 Gbps)，512 QAM/100 M-BR (0.9 Gbps) 的高速傳輸。與文獻比較，此相位陣列系統的表現相當具有競爭力。
本論文之第二部分的研究為以65奈米互補式金屬氧化物半導體製程實現35-39 GHz線性化差動同相與正交分量 (differential I/Q) 接收機晶片，應用於第五代行動通訊之毫米波相位陣列系統。本接收機使用多閘級電晶體線性器 (multi-gate transistor, MGTR) 與分割式疊接電晶體線性器 (splitting cascode transistors, SCTR) 分別整合於低雜訊放大器與降頻混頻器，以大幅壓抑三階交互調變訊號功率 (third-order intermodulation power, IM3)，進而提升接收機的1-dB功率壓縮點 (P1dB)，三階截斷點(IP3)以及三階交互調變訊號拒斥比 (third-harmonic rejection ratio，RR3)。根據此接收機晶片在38-GHz的量測結果，在線性器關閉與開啟的條件下比較，IP1dB提升6 dB，OP1dB提升2.4 dB (IP1dB由 -19 dBm 提升至-13 dBm，OP1dB 由-1.6 dBm提升至0.8 dBm)。根據雙調測試 (two-tone test)，IM3功率降低20-31 dB；IIP3提升13 dB，OIP3提升9.4 dB (IIP3由-11 dBm提升至2 dBm，OIP3由7.4 dBm提升至16.8 dBm)；RR3 小於-40 dBc時的最大中頻(IF)輸出功率提升7 dB (由-12 dBm提升至-5 dBm)，於-30 dBc時的最大中頻輸出功率提升3 dB (由-3 dBm提升至-2 dBm)。四象限振幅調變載波解調測試實驗結果，在較大的射頻與中頻功率操作時，四象限振幅調變載波的星座圖 (constellation diagram) 在線性器關閉的條件下呈現完全失真 (無法判別)，但在線性器開啟的條件下即回復成良好的星座圖。與文獻比較，本接收機具有良好的IP1dB，OIP3 數值；卓越的IM3功率壓抑能力使IP1dB，IP3，RR3大幅提升。此線性化接收機滿足第五代行動通訊毫米波相位陣列系統的高線性需求。
本論文之第三部分的研究為以0.1微米砷化鎵假晶高電子遷移率電晶體半導體製程實現之寬頻降頻混頻器。此降頻混頻器使用被動式冷偏壓 (cold-bias) 電晶體的電路設計實現射頻與中頻寬頻的降頻能力。此部分發表兩組毫米波降頻混頻器，第一組為具有高的LO-to-RF隔離度 (isolation) 的單端輸入 (single-ended) 寬頻降頻混頻器，操作頻率為RF 34-53 GHz與IF 4-12 GHz，並應用天文望遠鏡毫米波系統。此降頻器以電容-電感串聯共振電路實現良好的LO-to-RF隔離度，以克服傳統單端輸入混頻器具有較低LO-to-RF隔離度的問題。第二組為應用於5G K/Ka 全頻帶的單平衡 (single balanced) 寬頻降頻混頻器，操作頻率為RF 20-43 GHz與IF 0.1-6 GHz，並具有8-15 Gbps的數位調變訊號降頻能力。

關鍵字

第五代行動通訊毫米波系統 ； 38-GHz ； 相位陣列系 ； 互補式金屬氧化物半導體 ； 砷化鎵假晶高電子遷移率電晶體半導體 ； 發射機 ； 接收機 ； 邊緣輻射毫米波天線 ； 等效全向輻射功率 ； 波束掃描 ； 線性化 ； 多閘級電晶體線性器 ； 分割式疊接電晶體線性器 ； 三階交互調變訊號功率 ； 三階交互調變訊號拒斥比 ； 四象限振幅調變 ； 星座圖 ； 降頻器 ； 冷偏壓 ； 單端輸入 ； 電容-電感串聯共振電路 ； LO-to-RF 隔離度 ； 5G K/Ka 全頻帶 ； 每秒十億位元

並列摘要

The topic of this dissertation is the implementations of the phased array system and the receiver components for the fifth generation communication millimeter wave (5G MMW) systems. There are three parts of sub-topics in the dissertation.
The first part presents the 38-GHz phased array Tx (transmitter) and Rx (receiver) systems. The Tx and Rx beamformer ICs and up-/down converter ICs are fabricated in 65-nm CMOS (Complementary Metal-Oxide-Semiconductor). The PA and LNA ICs near the antenna-ends are fabricated in 0.15-μm GaAs pHEMT (Gallium Arsenide Pseudomorphic High Electron Mobility Transistor). The 8-element Tx and 4-element Rx phased array PCB (print circuit board) modules integrated with the multiple ICs and end-fire radiation antennas are implemented as the unit cells. And four pieces of the Tx modules are vertically stacked to construct an 8 × 4 brick array while four Rx modules are to construct an 4 × 4 array. According to the 38-GHz OTA (over the air) measurements, the 32-element Tx shows 47.5 dBm EIRP (equivalent isotropic radiated power) at OP1dB. The 16-element Rx shows -4 dBm OP1dB. The Tx and Rx support the beam-scanning around ±60° azimuth plane and ±30° elevation plane. The Tx-to-Rx wireless data link demonstrates the 64 QAM (quadrature amplitude modulation)/400 M-BR (baud rate), 256 QAM/200 M-BR, and 512 QAM/100 M-BR at 20 m link-distance. To the best of the authors’ knowledge, this work is the first 5G 37/39-GHz phased array Tx/Rx using the scalable brick array configuration and demonstrating competitive performances compared to previous works.
The second part proposes a 35-39 GHz linearized differential in-phase and quadrature components (I/Q) receiver (Rx) fabricated in 65-nm CMOS for 5G MMW phased-array systems with massive front-ends. The two linearization techniques, multi-gate transistor (MGTR) and splitting cascode transistors (SCTR) linearizers, are adopted at LNA and downconverter respectively which significantly cancel the 3rd-order intermodulation (IM3) power and enhance the P1dB, IP3, and third-harmonic rejection ratio (RR3). According to measurements at RF 38 GHz in the normal mode (linearizers off) and linearized mode (linearizers on), the IP1dB enhanced 6 dB, and the OP1dB enhanced 2.4 dB (IP1dB improved from -19 dBm to -13 dBm, and OP1dB improved from -1.6 dBm to 0.8 dBm.). According to the two-tone measurements, the IM3 power decreased by 20-31 dB with IIP3 enhancement of 13 dB and OIP3 enhancement of 9.4 dB (IIP3 improved from -11 dBm to 2 dBm, and OIP3 improved from 7.4 dBm to 16.8 dBm). The maximum IF power with RR3 < -40 dBc improved 7 dB (-12 dBm improved to -5 dBm) and the maximum IF power with RR3 < -30 dBc improved 3 dB (-5 dBm improved to -2 dBm) which exhibits a superior IM3 suppression capability in high power level. Furthermore, the QAM carrier demodulation test is demonstrated. In the large RF and IF power operation region, the measurement exhibits that the constellation diagram in normal mode is dispersed but recovered in linearized mode due to the improved RR3. Compared with the publications, the proposed Rx has the competitive IP1dB, OIP3, and significant IP1dB, IP3, RR3 improvement with IM3 suppression. To the authors’ knowledge, the proposed Rx exhibits the highest IF linear power with RR3 ≤ -30 dBc compared to the published Rxs and downconverters, and is the first MMW linearized Rx that demonstrates a capability of mitigation of QAM constellation diagrams distortions. This linearized Rx is satisfactory for the 5G phased-array systems with massive front-ends.
The third part proposes the wide RF and IF BW (bandwidth) downconverters fabricated in 0.1-μm GaAs pHEMT. The downconverters adopt the cold-bias transistors mixing cell to realize the wide RF BW and IF BW down-conversion. And the mixing cell is utilized to implement the two downconverters for different applications. The first one is a single-ended downconverter with 34-53 GHz RF and 4-12 GHz IF for the MMW astronomical telescope system which utilizes the series-LC (inductor/capacitor) resonated circuits to improve the LO-to-RF isolation. The proposed single-ended downconverter exhibits an excellent LO-to-RF isolation (37-61 dB) which is higher than the conventional single-ended downconverter and competitive to the balanced downconverters. The second one is a single balanced downconverter with 20-43 GHz RF and 0.6-6 GHz IF for the 5G K/Ka full band receivers. The proposed single balanced downconverter exhibits the wide RF and IF bandwidth with the low noise and good linearity which supports the digital modulation carrier (64 QAM and 256 QAM) down-conversion with the 8-15 Gbps (gigabit per second) data rate.

並列關鍵字

fifth generation communication millimeter wave (5G MMW) systems ； 38-GHz ； phased array ； transmitter (Tx) ； receiver (Rx) ； 65-nm CMOS (Complementary Metal-Oxide-Semiconductor) ； 0.15-μm GaAs pHEMT (Gallium arsenide Pseudomorphic High Electron Mobility Transistor) ； end-fire radiation antennas ； brick array ； OTA (over the air) ； EIRP (equivalent isotropic radiated power) ； beam scanning ； wireless data link ； QAM (quadrature amplitude modulation) ； linearization ； multi-gate transistor (MGTR) linearizer ； splitting cascode transistors (SCTR) linearizer ； 3rd-order intermodulation (IM3) ； third-harmonic rejection ratio (RR3) ； constellation diagram ； cold-bias transistors mixing cell ； LO-to-RF isolation ； 5G K/Ka full band ； Gbps (gigabit per second)

參考文獻

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