應用於物聯網使用注入式鎖定技巧之超低電壓無線收發機

Abstract

近年來，物聯網的應用日漸普及，是當前炙手可熱的技術重點之一。物聯網藉由設立在各處的感測節點讀取周遭環境的資訊後，將其取得的資訊或訊號傳到後端進行處理。因此，無線收發機是物聯網不可以或缺的一塊。 為了達到長時間使用及省電的目的，本論文提出了一個具有高能量效率的短距離通訊之無線收發機。本無線收發機以差分相位鍵移調變(DPSK)為系統之調變方式，採用注入式鎖定技巧完成調變與解調。 發送機採用次諧波注入鎖定，低頻訊號會經由相位選擇器選取相位後注入到高頻振盪器，改變高頻振盪器的相位資訊，以完成相位的調變。接收機則採用相位至振幅轉換的技巧來完成解調。接收之輸入訊號注入到震盪器中，當其相位產生變化時，震盪器的輸出振幅也會因此產生暫時性的變化，進而完成解調。此無線收發機為一開迴路架構，可大幅簡化電路設計的複雜度，進而減少功率的消耗。 本作品使用台積電180納米製程，頻段為400-457 MHz Med-Radio通訊傳輸頻帶，以0.5伏供應電壓來完成電路實現。資料傳輸量為10 Mbps，系統功耗為1.3 mW，能量效率為130 pJ/b。發送機的最大輸出功率為-10 dBm，誤差向量幅度為8.74 %，而接收機的靈敏度為-60 dBm。

The applications of Internet of things (IoT) have drawn more attentions recently. The sensor nodes set up in various places collect the information of the surrounding environment and transmit the information to the back-end system for further processing. Therefore, the wireless transceiver is a critical element of the IoT. In order to achieve long-term usage and power-saving purposes, this thesis proposes a wireless transceiver with high energy efficiency for short-range communications. The injection-locked technique and D-BPSK modulation/demodulation are adopted for this system. The subharmonic injection-locked technique is adopted in the transmitter. The multiplexer (MUX) selects the phase of low frequency and injects to high frequency oscillator. Therefore, the desired modulation can be achieved by changing the phase of a injection-locked oscillator. In the receiver, a phase-to-amplitude conversion based on the injection-locking technique is employed. It detects the phase transition of a D-BPSK signal and then convert to an amplitude variation. The open-loop architecture is adopted in this system, which reduces the complexity of the circuit design and power consumption. This work is fabricated in TSMC 180-nm CMOS technology. This wireless transceiver is operated at 400-457 MHz Med-Radio band. Supply voltage is 0.5 V and data rate is 10-Mbps. The total power consumption is 1.3 mW and equivalent energy efficiency is 130 pJ/b. The maximum output power of the transmitter is -10 dBm and 8.4 % error vector magnitude (EVM) is achieved. The sensitivity of receiver is -60 dBm.