本文介绍了一种用于5G多输入多输出（MIMO）应用的39 GHz收发机前端芯片组。每个芯片包括两个可变增益变频信道，可以支持两个同时独立的波束。该芯片还集成了一个本地振荡器链和数字模块，用于多芯片的扩展和增益状态控制。为了提高射频性能，针对前端系统中的关键构建模块提出了几种电路级改进技术。此外，还开发了先进的低温共烧陶瓷工艺，用于封装39 GHz双信道收发机芯片组，实现了低封装损耗和两个发射（TX）/接收（RX）信道之间的高隔离。通过进行芯片级和系统封装（SIP）级的测量，展示了收发机芯片组的性能。测量特性表明，TX SIP 提供11 dB 的最大增益和10 dBm饱和输出功率，而RX SIP实现52 dB的最大增益，5.4 dB噪声系数和7.2 dBm输出1 dB压缩点。收发机的单信道通信链路测试显示，对于64 次正交幅度调制（QAM），误差矢量幅度（EVM）为3.72%，频谱效率为3.25 位⋅s⁻¹⋅ Hz⁻¹。对于1 m距离内的256-QAM 调制，EVM为3.76%，频谱效率为3.9 位⋅s⁻¹⋅Hz⁻¹。在该芯片组的基础上，还开发了39 GHz的多波束原型，用于执行5G毫米波应用的MIMO操作。用于单流和双流传输的空中通信链路表明，多波束原型可以覆盖5~150 m的距离，具有相当的吞吐量。

This article presents a 39 GHz transceiver front-end chipset for 5G multi-input multi-output (MIMO) applications. Each chip includes two variable-gain frequency-conversion channels and can support two simultaneous independent beams, and the chips also integrate a local-oscillator chain and digital module for multi-chip extension and gain-state control. To improve the radio-frequency performance, several circuit-level improvement techniques are proposed for the key building blocks in the front-end system. Furthermore, an advanced low-temperature co-fired ceramic process is developed to package the 39 GHz dual-channel transceiver chipset, and it achieves low packaging loss and high isolation between the two transmitting (TX)/receiving (RX) channels. Both the chip-level and system-in-package (SIP)-level measurements are conducted to demonstrate the performance of the transceiver chipset. The measurement characteristics show that the TX SIP provides 11 dB maximum gain and 10 dBm saturated output power, while the RX SIP achieves 52 dB maximum gain, 5.4 dB noise figure, and 7.2 dBm output 1 dB compression point. Single-channel communication link testing of the transceiver exhibits an error vector magnitude (EVM) of 3.72% and a spectral efficiency of 3.25 bit·s⁻¹·Hz⁻¹ for 64-quadrature amplitude modulation (QAM) modulation and an EVM of 3.76% and spectral efficiency of 3.9 bit·s⁻¹·Hz⁻¹ for 256-QAM modulation over a 1 m distance. Based on the chipset, a 39 GHz multi-beam prototype is also developed to perform the MIMO operation for 5G millimetre wave applications. The over-the-air communication link for one- and two-stream transmission indicates that the multi-beam prototype can cover a 5–150 m distance with comparable throughput.