Method for Mixer and Non-linear Device Noise Parameter Measurement


Description of Technology

A mixer or frequency mixer is an electronic circuit that creates new frequencies from two signals applied to it. As any electronic device, mixers generate additional noise and reduce signal-to-noise ratio. Also, mixers convert noise from frequencies located in different harmonic side bands (HSBs), which appear in the mixer output. In devices where mixer noise affects overall sensitivity, an understanding of how to minimize noise in a mixer system is crucial.

Researchers at the University of Calgary have developed a novel method for modeling and measuring noise parameters of a mixer. The active mixer noise model has different sets of noise parameters for every input frequency band that contributes noise to the output. The invention can be used to accurately calculate the sensitivity trade-off between mixer input power matching and noise matching. As a special case for noise parameter measurements, non-linear devices, such as power amplifiers, are considered as mixers with RF, LO and IF ports being at the same frequency, where RF represents the noise at the input, LO represents the amplifier input signal, and IF represents the output signal. Noise conversion from frequencies around LO harmonics contribute to the output noise of such devices.

Areas of Application
  • Communications and navigation systems
  • Phase detector
  • Military radar
  • Cellular base stations
  • Signal shifting and identification
  • Phase modulators
IP Status
Competitive Advantages

This novel method allows for the measurement of the mixer and non-linear circuit noise parameters and thus noise correlation coefficients that fully characterize the behavior of noise of a given device.

  • Can be used to specify antenna impedance for better system signal-to-noise ratio
  • Can predict system level performance better than conventional techniques
  • Can minimize noise distribution of each HSB