Sweep dynamic range into mixer measurements

To achieve high dynamic range, critical for ECM applications, receiving systems must operate within low levels of intermodulation distortion (IMD). Mixers are generally the dominant contributors to IMD generation in receiving systems. The present paper describes a basic swept-frequency IMD-measuring setup where the RF two-tone and LO frequencies are swept together by a common generator; the setup is designed for the following frequencies: f(RF-1) = 80-430 MHz, f(RF-2) = 90-440 MHz, f(LO) = 150-500 MHz. The setup is capable of testing mixers with as much as +30 dBm LO drive and 0 dBm RF power, and has up to 95 dB dynamic range.