By the way, my business is much like yours. I do everything from sticking labels on and going to the post office to doing the conceptual design and schematic and board layout, the exception being the financial nonsense which is graciously and thankfully dealt with by a long suffering family member.
The few, the proud! Great to hear someone has chosen a similar path. I regularly second guess my decisions.
I am not an HDMI expert at all other than to know to buy my cables from the dollar store ;-) but 3Gbps doesn't mean 3GHz. A raw NRZ signal transitioning every bit gives a maximum frequency of half the bitrate, ie 1.5GHz.
This is HD-SDI SMPTE-292 and SMPTE-424 Serial digital over 75 ohm coax.
From what I know so far, the 292 variety maxes out a 1.8Ghz and the 424 is 3.6Ghz signaling. I have held off on purchasing the spec from SMPTE since I won't need it if I don't win, but that is my understanding.
I would need to design and validate the singe ended inputs and outputs and validate the function of the line drivers, equalizers, and re-clockers. Once inside the the signals are 100Ohm differential and go through a de-serializer. At that point the data rates obviously slow down in the parallel world. That data has to be time correlated with a variety of other signals, audio, sync, time code, data, etc. that come from other non-sync sources. After some processing it has to be re-assembled and the timing worked out. Jitter and other signal integrity factors are critical and unforgiving. Obviously will have a lot to learn, but that has been how I approach everything. Head on - if I don't know it - I LEARN IT. I love learning.
Side story:
When I decided to start my mechanical design and manufacturing company. I simply purchased SolidWorks and a CNC milling machine and started looking for the "on' button. I literally had no idea how to turn the machine on or how to put tools in it or what tools I needed. By brute force, I learned the trade and learned it well enough that I could no longer outsource parts because most machine shops could not produce what I was making. That is when I got out and moved into electronics where I have been brute forcing knowledge into my brain as fast as possible. What a blast!