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Freedom of Choice

You can enjoy greater freedom of choice when representing time steps in Systems Tool Kit (STK) if you think outside the box and use STK Analysis Workbench. 

Recently, I helped a customer who wanted to report the distance between a jammer and a receiver for the entirety of a scenario alongside the communication quality between their receiver and transmitter whenever they were in view of one another. Communication quality between the receiver and transmitter can only be reported when the two can establish a link. By default, STK reports these values separately from the range between the jammer and the receiver, which are values that are available for the duration of the scenario. Because of the different functions of these two sets, a single report with every time step would contain gaps in which one object was irrelevant to the other dataset.

Fortunately, it’s easy to create a report containing Bit Error Ratio + Interface (BER+I) values for a receiver and a transmitter with range values between a receiver and a jammer. The values are reported on the time step specified for the BER+I report and will span the entire scenario interval unless otherwise limited.  The method that I shared with the customer is presented below. You can use this method for any two data providers: 

  1. Create a custom report with your Time and BER + I values.
  2. Generate the report (set the time step you'll want for later because you can't change it after this step).
  3. Save the report as a .txt file. 
  4. Open a .csc file template (here is a link to a model file, and here is a link explaining how these files are built and what is necessary or optional in their build). 
  5. Copy your data times and values from the generated report in the section of the file between BEGIN Time Values and END Time Values. Change the Number of Points lines to the number of points you have (it'll be the number of lines on your generated report minus 10).
  6. In STK, open Analysis Workbench. 
  7. Make the parent object for all the following steps a facility (it could be any object you choose as parent).
  8. Create a new vector that is a displacement between the two points that you want to use to calculate range. 
  9. Navigate to the Calculation tab. 
  10. Select New Scalar Calculation, change the type to file and click the ellipsis button to select the .csc file that you created. 
  11. Select New Scalar Calculation again, make the type Vector Magnitude and select the range vector that you created.
  12. Open Report and Graph Manager again and make a new report for the facility.
  13. Navigate to the scalar folder and expand the two scalars that you just made. Select time for one of them and scalar for both.  
  14. Click OK to close the custom report properties window. Your report is built. 

Good luck using STK to report and visualize your data! 

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STK Analysis Workbench

Create custom functions and calculations relative to times, positions, and reference frames.