Low-noise correlation measurements based on software-defined-radio receivers and cooled microwave amplifiers

We present amicrowave correlationmeasurementsystem based on two low-cost USB-connectedsoftware defined radio dongles modified to operate as coherent receivers by using a common local oscillator. Existingsoftware is used to obtain I/Q samples from both dongles simultaneously at asoftware tunable frequency. To achieve lownoise, we introduce an easy low-noise solution forcryogenic amplification at 600 –900 MHz based on single discreteHEMT with 21 dB gain and 7 Knoise temperature. In addition, we discuss the quantization effects in a digital correlationmeasurement and determination of optimal integration time by applying Allan deviation analysis.

Source: Review of Scientific Instruments - November 16, 2016 Category: Physics Authors: Teemu Nieminen, Pasi L ähteenmäki, Zhenbing Tan, Daniel Cox and Pertti J. Hakonen Source Type: research