A Solution to the RFID Reader Interference Problem using Adaptive Beam-forming Approach

Radio frequency identification (RFID) is one of the most attractive and futuristic technologies that can identify an object or person wirelessly, using electromagnetic radio waves. In a multiple reader RFID system, the reader interference problem is a very common phenomenon. Efforts are required to minimize this problem as performance, speed and reliability of the entire system highly depends on our ability to solve this problem efficiently. A simple adaptive beam-forming technique is proposed for solving the reader interference problem in a multiple reader RFID system. This new approach is able to effectively generate deep nulls at the direction of interference and respond to the direction of our desired signal. Simulations are carried out to evaluate the performance of our adaptive beam-forming approach and the results confirmed that, the proposed method can adaptively generate a high gain beam to the desired signal direction to acquire and track the signal completely, and it can generate deep nulls at the direction of other readers effectively to avoid interference. Moreover, this method has been found to be very efficient in terms of Bit Error Rate and energy consumption.