一种下变频电路的研究与设计

Research and Design of a Downconversion Circuit

针对机载相控阵雷达集成化需求,本文设计并实现了一种小型化下变频模块。该模块基于三维集成的设计理念和陶瓷一体化封装技术,利用ADS等仿真软件对该模块链路预算及频率交调等情况做仿真分析设计,采用电磁场仿真工具HFSS对组件腔体效应、射频信号三维垂直互连传输模型进行建模仿真,并合理布局内部电路等,实现了组件的高性能集成。仿真和测试结果表明各项指标均满足系统要求,电路的可靠性和可制造性也得到充分验证,可以广泛应用于地面、机载等平台的相控阵雷达。测试结果显示:100MHz工作带宽内,组件通道增益27±0.5dB、P_(-1)输出≥17.6dBm、噪声系数≤4dB、本振隔离度≥60dBc、带内杂散抑制≥70dBc、端口驻波≤1.8。

A miniaturized downconversion module is designed and implemented for an integrated airborne phased array radar system.Based on the design concept of 3D integration,the technology of integral substrate package of high-temperature co-fired ceramic(HTCC)is applied for the module.The key technical specifications such as the gain,noise figure as well as spurious and harmonic wave suppression are simulated and analyzed using ADS.Then,HFSS is used to simulate the cavity effect of the microwave modules and the 3D vertical interconnection structures.In addition,the internal circuits are well configured to realize high-performance integration.The simulation and test results show that all requirements of the radar system are met.The reliability and manufacturability of the circuit are fully proved.It can be used in various airborne and ground-based phased array radar systems.The measured results show a channel gain of 27±0.5dB at 100MHz operating bandwidth,an output power of not less than 17.6dBm at 1dB compression point(P1dB),a noise figure of up to 4dB,an LO isolation of not less than 60dBc,an in-band spurious wave suppression of not less than 70dBc,and a port voltage standing wave ratio(VSWR)of up to 1.8.