Indoor Positioning based on RSSI of WiFi signals: how accurate can it be?

There is abundant literature on positioning systems based on WiFi signals. Most of the systems with off-the-shelf hardware use RSSI measurements. In this paper, we try to determine the highest achievable accuracy of such systems. Instead of resorting to a theoretical analysis, e.g., Cramér-Rao or Ziv-Zakai bounds, we apply state-of-the-art localization algorithms to measurements in a well-controlled experimental setup. We conclude that an accuracy of less than 1 meter seems unrealistic.