基于电源调制及有源滤波匹配的双向放大器芯片设计

射频双向放大器作为雷达接收通道的前端模块芯片,其性能的优劣直接影响通道的性能。传统的双向放大器芯片往往是基于射频开关的拓扑结构设计的,在噪声性能和反向隔离度方面都有所不足。文中设计基于电源调制的双向放大器芯片,具有全新的电路拓扑结构,射频信号不通过射频开关而直接进入低噪声放大器,可以优化芯片的噪声性能;同时,截止的器件可以提高芯片的反向隔离度。设计中如何提高低噪声放大器的增益和噪声性能,以及如何利用有源滤波匹配技术实现射频输入输出端口的合并和匹配是两大难点和创新点。文中基于L 波段的双向放大器设计及流片的测试结果显示,芯片有良好的性能,充分验证了理论分析的正确性。

Design of Bidirectional Amplifier Chip Based on Power Modulation and Active Filter Matching

The performance of radio frequency (RF) bidirectional amplifier is an important factor of radar receiver due to its connection to antenna in first position of the module. The traditional topology of RF bidirectional amplifier is based on RF switches. The performance on noise figure and isolation is limited by the switches. A new topology has been selected in this design. The RF port is directly connected to low noise amplifier which can optimize the noise figure. The cut-off device can enhance the reverse isolation simultaneously. In this design, how to enhance the gain and reduce the noise figure of the low noise amplifier (LNA) is a key technology. On the other hand how to combine the input and output RF port based on active filter matching is an innovation point. The schematic, layout and tape-out is based on L-band frequency. The test result shows the chip has outstanding performance, demonstrating the correctness of theoretical analysis.