一种高线性短波宽带混频器的设计

Design of a Short-wave Broadband Mixer with High Linearity

采用双平衡场效应管结构和阻抗匹配技术设计了一种适用于短波宽带接收机的高线性混频器,通过调整场效应管的沟道宽度和偏置电压优化了混频器的性能指标。该混频器射频输入频率为1.5～30 MHz,本振输入频率为71.5～100 MHz,中频输出频率为70 MHz。测试结果表明:输入三阶截点高于40 dBm,变频损耗小于7 dB,1 dB压缩点高于12 dBm,单边带噪声系数小于7 dB。

The structure of double-balance fidd effect transistor and resistance-match technology are used to design a high linearity mixer for the short-wave broadband receiver. The channel-width and bias-voltage of the field effect transistor are adjusted to optimize the mixer＇s performance.The RF frequency is 1.5- 30 MHz,the LO frequency is 71.5- 100 MHz and the IF frequency is 70 MHz. The test results show that the IIP3 is above 40 dBm, the conversion loss is lower than 7 dB, IP_ 1 dB is above 12 dBm and SSB noise figure is lower than 7 dB.