Radio noise and electromagnetic interference (EMI) can cause significant problems to all receive sites and especially to fixed High Frequency sites designed to be electrically quiet. Long Wave has established an effective method of measuring, and mitigating this noise using a team approach built on proven techniques. While this approach is very effective it depends heavily on subject matter experts being present in the field during measurements. In the past we used measurement equipment that was no longer supportable and not capable of automation.
Long Wave Inc. modernized the hardware and software used for noise abatement, site integrity maintenance, noise surveys, and related areas such as signal intelligence and noise signature identification. We developed the Automatic Noise Analysis Tool (ANAT), which automates existing techniques so the results are more accurate and can perform a majority of the work automatically. The automation allows for experienced experts (SMEs) to travel less, and spend their time concentrating more on analyzing the data rather than collecting it, thereby improving the use of manpower, improving efficiency, and reducing cost.
This LWI Automatic Noise Analysis Tool successfully eliminates key dependencies on the unsupportable test equipment, like the HP141T and Develco 7200B, that has blocked progress toward a more automatic system. Long Wave’s system can be programmed to work with any modern spectrum analyzer and provides data and analyzer settings to the noise abatement engineer. Our software automatically plots the data in real time, and in three dimensions showing the time history.
- Performs the same functions of obsolete test and plotting equipment
- Eliminates dependency on unsupportable equipment
- Provides the capability to record noise measurement site data at a receive site for later analysis, paving the way for automated analysis and cost reductions
- Provides the ability to automatically label plots for reporting (a huge time savings)
LWI software based replacement to the Develco 7200B-axis time history unit being operated and evaluated during a recent field measurement.
LWI PC interface screen allows for image scaling, logging, plotting, viewing and rotating. As well as compressing, expanding and printing or tagging.
With just the mouse or keypad the user can manipulate the plot image in all three axis where X is frequency, Y is amplitude, and Z is time.
Multiple image views are available for the user. The user can also set up the scale of the axis so that any image printed or tagged for later use can be used without the need for further work.
Screen shot showing spectral distribution of six major reoccurring events from 14.95 MHz to 15.02 MHz
Some key features of the LWI interface unit and PC based software include:
- The LWI interface unit can be programmed to work with most modern spectrum analyzers, enabling work at virtually any frequency, and enabling automatic control from remote location
- The unit is capable of continuous recording of time history data in a format that can be logged to memory and analyzed later, thus reducing and in some cases eliminating the need for a full time operator being present as is currently required
- The unit allows for automatic labeling of axis plot, thus eliminating this currently manual step
- The unit is continuously recording time history data in a format that can be logged to memory and analyzed later which also enables the possible use of “artificial intelligence like algorithms” to sort the data flagging events of interest thus reducing the labor required
- Significant reduction is size and weight of the more automated equipment makes the near real time deployment during phase inspections feasible, this helps maintaining site integrity and is cost effective
- As capability evolves via automation of the new system, a remote monitored measurement system may become feasible as a full time site integrity maintenance system