在物联网应用中部署WiFi/蓝牙双模收发机至关重要，它提供了灵活的连接选项，能够在高速WiFi数据传输和低功耗、短距离的蓝牙通信之间无缝切换。这种集成由于需要在时分双工操作中同时支持两种协议，提出了独特的挑战。本论文通过关注接收系统，特别是收发切换开关、低噪声放大器（Low Noise Amplifier， LNA）和失配校准电路来应对这些挑战。本文提出了一种收发切换开关，通过调谐匹配网络进行时分复用。该开关在功率放大器操作期间有效地将LNA输入短接到地，反之在LNA活动时呈现高阻抗负载，实现了高隔离度（33 dB）和低插入损耗（0.2 dB）。这种设计避免了在RF路径中包含有源器件，优化了蓝牙和WiFi的接收性能。所实现的LNA采用电容交叉耦合结构，并配备直接分流调节增益方案，专门满足WiFi的线性要求和蓝牙的能效需求。集成了收发开关的LNA提供了16 dB的可调增益范围，最大增益达到25 dB，并实现了超过20 dBm的输出第三阶截取点（Output Intercept Point， OIP3）、低于-20 dB的输入反射系数、3.8 dB的最小噪声系数以及1.8 mW的功耗。与传统方法相比，所提方法在8.5 dB增益变化中提高了5.3 dB的线性度。此外，论文还开发出了一种新颖的算法和电路设计，用于校准I/Q失配和直流偏移，这对于抵消生产过程中的工艺偏差至关重要。该校准方法基于谐波成分检测，有效地利用频谱搬移特性来识别和纠正失配，确保收发机功能的准确性和可靠性。接收机采用22 nm工艺制造，第二版接收机的后仿真结果显示电压增益为46 dB，OIP3为20 dBm，基带噪声系数为4.1 dB，总功耗为6.5 mW。初版LNA测试结果显示电压增益为40.91 dB，功率增益为31.91 dB，最小噪声系数为2.97 dB，OIP3为9.97 dB，功耗为1.8 mW。本论文通过创新的电路设计和校准策略，推进了在物联网环境中WiFi/蓝牙双模收发器的整合，提升了性能和效率。
Deploying WiFi/Bluetooth dual-mode transceivers in Internet of Things (IoT) applications is crucial, as they offer flexible connectivity options, enabling seamless switching between high-speed WiFi data transmission and low-power, short-range Bluetooth communication. This integration poses unique challenges due to the need to support both protocols simultaneously in time-division duplex (TDD) operations. This thesis addresses these challenges by focusing on the receiver system, particularly the transmit/receive switch, low noise amplifier (LNA), and mismatch calibration circuits.This thesis proposes a transmit/receive switch that utilizes a tuned matching network for TDD operation. This switch effectively grounds the LNA input during the power amplifier‘s operation, and presents a high impedance load when the LNA is active, achieving high isolation (33 dB) and low insertion loss (0.2 dB). This design avoids including active devices in the RF path, optimizing the reception performance for both Bluetooth and WiFi.The implemented LNA uses a capacitor cross-coupling structure and is equipped with a direct shunt for gain adjustment, specifically meeting the linearity requirements for WiFi and the energy efficiency needs for Bluetooth. Integrated with a transmit/receive switch, the LNA provides a 16 dB adjustable gain range, a maximum gain of 25 dB, an output third order intercept point (OIP3) of over 20 dBm, an input reflection coefficient below -20 dB, a minimum noise figure of 3.8 dB, and consumes only 1.8 mW. Compared to traditional methods, this approach improves linearity by 5.3 dB with an 8.5 dB gain change.Furthermore, the thesis develops a novel algorithm and circuit design for calibrating I/Q mismatch and DC offset, crucial for offsetting process variations during production. The calibration method, based on harmonic component detection, effectively utilizes spectral shift characteristics to identify and correct mismatches, ensuring the transceiver‘s accuracy and reliability.The receiver is fabricated using a 22 nm process. Post-simulation results for the second version receiver show a voltage gain of 46 dB, an OIP3 of 20 dBm, a baseband noise figure of 4.1 dB, and a total power consumption of 6.5 mW. Testing results for the first version LNA indicate a voltage gain of 40.91 dB, a power gain of 31.91 dB, a minimum noise figure of 2.97 dB, and an OIP3 of 9.97 dB, with a power consumption of 1.8 mW.Through innovative circuit design and calibration strategies, this thesis significantly advances the integration of WiFi/Bluetooth dual-mode transceivers in IoT environments, enhancing both performance and efficiency.
