[TangerineSDR] ray tracing and terrain analysis

[Ramakrishnan Muthukrishnan]

Hello HamSCI hackers!

This is my first email to this list although I have been hanging out in this list for long. I am a long time SDR enthusiast and a programmer. Someone recently demonstrated the old ARRL program that came with the antenna book CD called HFTA written by Dean Straw. It is of course, a closed source program. Being a GNU/Linux user and free software supporter, it was a bit of a struggle to even get it to run under wine. I saw a couple of slidesets about HFTA. From what I understand, it does the following:

- It takes a from location and a to location as inputs and the type of Tx antenna and its height.
- It has limited antenna simulation capability and it uses the information and some ray tracing to plot the rx signal strength (or a figure of merit) for various elevation angles.
- It also needs the terrain data as input.
- from what I understand, it uses difraction + reflection from ionosphere and the terrain to map the signal strength figure of merit at the rx location.

Perhaps it does a lot more.

My question to this group: I would like to write a free software alternative to this program and use whatever knowledge that HamSCI has gained over the last few years working on this stuff. Has anyone done any research on how to go about it? I would like to collaborate in building some free software around it so that everyone benefits from reading the code and learning how this works.

73
-- 
  Ram VU2JXN