데이터 신뢰도를 고려한 저전력 TPMS 양방향 통신기법

Abstract

TPMS (Tire Pressure Monitoring System) is a wireless communication device used for vehicle, and can be defined as a safety support system for vehicle operation by efficiently managing information such as the tire pressure and temperature, to maintain the optimal tire operation conditions. TPMS transmits the data measured by the sensor unit through the wireless communication to the signal processor unit within the vehicle, and a battery is used for such data transmission. On average, the battery life is about 7 years, and the problem is that TPMS itself must be replaced according to the battery life. In order to maximize the power efficiency of batteries used for TPMS, this study suggests a data structure for duplex wireless communication. Computer simulation will verify the performance of technology suggested in this paper. Because TPMS uses wireless communication, it creates communication failure due to various noises and interferences when receiving/transmitting data. In order to prevent tire accidents which are directly related to the driver’s safety, and improve data reliability for the TPMS wireless communications, this thesis suggests a reliability evaluation method for determining the data reliability by measuring SINR (signal-to-interference and noise ratio) of the received signal at the receiver. The method suggested in this paper will be able to used widely not only for TPMS but also for duplex communication system based on a sensor. The computer simulation will verify critical SINR values satisfying reliability rates of 95%, 97%, and 99%. When the data measured at TPMS sensor unit is transmitted to the signal processing unit inside the vehicle, it suffers from various interferences that causes communication failure. In order to remove such interference, some papers have studied for interference suppression by using beamforming technology such as Switching Beamformer, GSC(Generalized Sidelobe Canceler) Beamformer, MVDR(Minimum Variance Distortionless Response) Beamformer, etc. In this paper, the complexity of these beamformers that are effective in removing TPMS interference are calculated to mathematically compare them. The computer simulation will verify the complexity of three beamformers introduced in this paper.