Simulink Model (and other information) of the Brooks Shera (W5OJM) GPSDO. These files go with my blogpost on this topic at: http://k6jca.blogspot.com/2018/12/simulating-brooks-shera-w5ojm-gpsdo.html
This respository contains my Simulink model (.SLX file) of the Brooks Shera GPSDO, created from the comments and code in Rev 1.28 of his PIC software.
This simulation model was created using MATLAB version R2018B.
I have also included a PDF of a printout scan of Shera's PIC code (Rev. 1.28). Please feel free to verify this source code against my model. (And my apologies for the PDF -- my copy of the actual source code file disappeared long long ago).
I've included two Excel .XLSX files that contain 1 PPS jitter information. The first file is jitter from a Quectel L76 GPS receiver, and the other file is jitter from a Trimble Resolution T GPS receiver. Either file can be used in the Simulink model to simulate the PLL's response to jitter noise.
Please note that I might have made a mistake in my equations, assumptions, drawings, or interpretations. If you see anything you believe to be in error or if anything is confusing, please feel free to contact me at:
jca1955 'at' sbcglobal 'dot' net
And so I should add -- this information is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.