Well. It seems I have missed the deadline for project completion.
Present state of the project:
1) Soldering the circuit boards is complete
2) Communication between all the Arduinos verified to be working individually. (Wireless communication, I2C)
3) Verified that the ID side Arduino boots fast enough (on wireless power) for the application to be practical
4) Most of the code written but still in pieces
Probably the messiest "proof-of-concept" ever:
The circuit boards:
I have decided to use Arduino Uno instead of Arduino Yun with the stationary module because Arduino Yun has issues powering the wireless chip. I will most probably require a separate 3.3V regulator to provide adequate current to the chip with a Yun.
While the project is probably ineligible to be judged for the challenge, I would still like to complete it in the next two days (weekends coming up).
For now, I will write a program on Processing which will find and parse the data relevant to the unique ID.
I would like to thanks Element14, Würth Elektronik and all the community members for making my FIRST RoadTest Challenge possible and this enjoyable. I also sincerely apologize for my inability to complete the project in time.