| With the development of Internet of Things(IOT),Radio Frequency Identification(RPID))technology plays a significant role.However,the Ultra High Frequency(UHF)RFID systems still suffer from several problems:(a)The maximum reading distance of UHF RFID reader is about 10 meters at present,which restricts the widespread use of UHF RFID technology.(b)Another key issue is that the recognition rate cannot achieve 100%.(c)At present,the method of solving the anti-collision is mainly from the software algorithm and is difficult to achieve efficient results,if there is a hardware support,can make more effective.In view of the above problems,this paper applies smart antenna to UHF RPID systems.The smart antenna could use the combination of antenna array element to carry out signal processing and adjust transmitting and receiving direction pattern automatically.The adaptive beam switching control algorithm that adapts to the UHF RFID system is proposed in this paper.This paper introduces the composition and working principle of RFID system at first,and then introduces the classification of smart antenna in detail.The reason of using beam-switching smart antenna in RFID system is described.According to the working principle of beam-switching antenna,and combined with the channel model of reader and tags,proposed the fixed dwell time adaptive beam switching control algorithm firstly.According to the fixed dwell time adaptive beam switching control algorithm need to matching the number of tags,which would cause the waste of time slot,put forward proposed the dynamic dwell time adaptive beam switching control algorithm.These two algorithms have been able to meet the general needs of most RFID readers.The RFID reader has been in full power state,more energy and indirectly affect the reader’s life,this paper constructs the beam-switching adaptive model based on power-control,and proposed the adaptive beam-switching algorithm based on power-control.Divide the Identify regions into block regions by control the reader’s transmit power,scheduling these block regions through the red black tree(RB-Tree).The proposed adaptive beam switching control algorithm can reduce the recognition time and energy consumption efficiently.We use MATLAB to simulate the algorithms that discussed in this paper,the results show that the beam-switching antenna applied in RFID system,combined with the adaptive beam-switching control algorithm can effectively extend recognition area and reduce the collision,reduce the consuming time and recognition energy as well.There is no need to modify the existing standards and protocols,can make the maximum identification distance system doubled.Positive impact on the large-scale application of passive ultra high frequency RFID system. |
