Development Of Antennas In The Vehicle Identification System For Internet Of Vehicles

RFID is the key technology of Internet of Vehicles.With the popularization of automobiles,the number of vehicles are increasing a lot,which causes congestion of traffic much more seriously.We require much higher velocity of the vehicles,especially at the toll gate of the expressway.Improving the pass rate of the vehicles' quantity at the same time is particularly important now.As the gate landing time is fixed,the distance among the vehicles gets longer when the speed gets larger at this time.With the improvement of speed,it inevitably has higher demand in the distance recognition of the RFID when the vehicles passing through the toll gate.At the same time,for the multi lanes,it proposes higher requirements of the angel of the RFID vehicle identification system.This article focuses on the method to solve the above issues.First,we design a high-gain reader antenna,a near field antenna and a high sensitivity vehicle electronic tag to solve the problem of distance reading.Next,we calculate the required reading distance by the calculation of the vehicle speed and road strobe opening time.Then,through the reading distance,the design index like antenna gain and tag sensitivity of the RFID are figured out.In the research of high-gain reader-writer,we improve the gain by the design of array antenna,then control the angle by the arraying form.As for the vehicle electronic tag,the high sensitivity is achieved by the design of broadband omnidirectional band dipole.To deal with the demand for high gain of the RFID reader antenna,we use the multi-layer microstrip antenna array is as the array element.The gain is improved by using the 1×4 linear array,and the array has the same phase of the feed network.A coaxial line is used as the feed line for the feeder network.The electronic tag of the vehicle adopts the deformation of the dipole antenna with T-type,thus,we design the broadband electronic tag.Because the tag chip impedance is complex imp edance,the conjugate matching between the tag antenna and the tag chip is adopted.And we use high dielectric constant ceramic substrate to reduce the length of the antenna.To solve the problem of misreading,the near-field antenna is designed in the form of loop antenna.We modify the current distribution on the ring line through the antenna bending,and effectively control the read range of antenna.The effectiveness of the design is verified by simulation or making samples.Finally,the design of RFID reader antenna and electronic tag is tested,and the reliability of the design is verified.The recognition distance of the system is improved by increasing the antenna gain and tag sensitivity.We effectively improves the vehicle pass rate and solve the problems such as adjacent channel misreading and et al.We also solve the highest demand on the hardware of IOV,which improves the vehicle pass rate through toll stations,and promotes the application of RFID in Internet of Vehicles.