I don't really understand your project description.
each led bulb will be set up different locations of the model house, each will be transmitting a character repeatedly
How can an LED transmit an 'A'? Why does it need to do it repeatedly? If you didn't hear it the first time, what makes you think you'll hear it the next time?
for example if it receives 'A' the user will be told s/he is the office.
Why would you want to call the user an office? Being told that the user is IN the office might be useful, IF the blind person's home had an office. If it has more than one, that knowing that you were in one of the offices wouldn't be all that useful.
I'm relatively certain that blind people are far more spatially aware than sighted people, so being told "you are in the bathroom" doesn't seem like useful information.
I'm not trying to put down your project. I simply think that you need to do a better job of explaining the whole project.