jremington:
Other things being equal, the RSSI value depends much more strongly on relative antenna orientation and absorption or interference effects than it does on distance, so it is nearly useless as a distance measure.There are exceptions under very carefully controlled circumstances, of course.
Its a project requirement though, and I usually do the experiments in the same place (the only controlled constant I can do). I will keep updating on my work before my project comes to an end.
Thanks to all that have given me guidance and feedbacks!