With MathWorks tools, YarCom used various hardware devices to continually monitor and detect immediate and long-term noise interference. This enabled a small expert team to return to the victim receiver sites only when problems were detected.
“MATLAB lets us accomplish 300% of what we could have done seven to ten years ago,” says Dr. Lott. “Now we instrument a site with two to three people, spend a few days on site to set up, and return to the site only when a problem is detected with just three to five equipment cases.”
YarCom engineers first used Instrument Control Toolbox™ and Data Acquisition Toolbox™ in a stimulus-response test setup. They used Data Acquisition Toolbox to sample signals in the victim receiver’s IF and AF spectrums via acquisition hardware, and Instrument Control Toolbox to sample the overall RF spectrum. They controlled stimulus transceivers using MATLAB serial port commands. “With the combination of MATLAB tools, we can measure RF, IF, and AF from one software control and analysis platform.”
With Instrument Control Toolbox, YarCom engineers quickly wrote custom scripts for the Agilent ESA-E 440xB family of spectrum analyzers to observe transient noise and interference. Using the scripts with the analyzers enabled them to obtain more than 25 1024-point observations per second with the fastest instrument internal numeric formats, which minimize data transfer times over the GPIB (IEEE-488) bus.
Next, Dr. Lott and his team used Communications Toolbox™, Statistics and Machine Learning Toolbox™, and Signal Processing Toolbox™ to analyze the collected data and identify interference. Mapping Toolbox helped them place the results from the report within a geographic context and locate sources of interference.
YarCom realized an additional benefit of the project by developing a new method for quantifying the critical Probability of Mission Success metric. Implemented in MATLAB as a 3D image, the “Lott Plot” represents the probability density functions for expected signal values compared with measured noise statistics.
A subcontractor to Integrated Engineering Concepts Inc., YarCom continues its work through the DoD’s Signal to Noise Enhancement Program (SNEP).