The optimization control of UHF reader transmit power

Radio Frequency Identification (RFID) technology is more widely used in all walks of life. UHF RFID technology is attracting more and more attention and study because of its advantages including read and write distance. Power amplifiers occupy the majority of energy consumption in the power consumption of UHF reader. In most applications, in order to maximize the read distance, transmit power is usually set to maximum which results in waste of energy, increasing the collision probability among the readers which leads to the decline of tag read rate. This paper describes a dynamic and intelligent transmit power control method. By theoretical analysis and practical application of the situation, the relationship among the distance between measured object and antenna, change rate of the number of tags and transmit power can be known. The fuzzy inference machine to adjust the transmit power with the distance between the tagged objects and reader measured by ultrasonic sensors, the change rate of tags. The energy consumption of reader and the collision between readers can be reduced with the adjusted power.