Interesting idea, for mapping you can treat each RFID tag as a point marker, collect the RSSI from multiple readers and use trilateration to estimate coordinates. Because RSSI is noisy, a weighted least‑squares fit or a Kalman filter can smooth the estimates. Keep the map in a simple 2‑D grid or array and update it whenever you get new readings. If the space is three‑dimensional, just add a height layer for each floor or level. You’ll need to calibrate the RSSI‑distance curve first—a quick linear regression on a few test points works well. Let me know if you need the exact equations or help setting up the filter.