| With the rapid development of smart city,Internet of Things,mobile Internet and other related industries,people's demand for high-precision location services is growing stronger.People spend more than 80% of their time indoors in their daily lives.Indoors are not only a place to live,but also a workplace.Therefore,the development of indoor location service is crucial to production and life.Ultra-wideband technology is a new type of wireless communication technology emerging in recent years that is different from other traditional communication technology.It does not require a carrier and only transmits signals by transmitting and receiving very narrow pulses,thus having the bandwidth of 3.1~10.6GHz.UWB technology provides excellent solutions for high-precision indoor positioning services due to its high temporal and spatial resolution,strong penetrating ability,strong anti-interference ability and low transmission power.It has better performance in wireless indoor positioning application prospects.Based on the definition and characteristics of UWB technology,this paper introduces two essential steps in the application of indoor positioning.firstly,the parameter measurement part,analyzes the principle and model of several parameter measurement methods applicable to ultra-wideband,such as Time of Arrival,Time Difference of Arrival,Received Signal Strength Indication.and Angle of Arrival.Followed by the position estimation algorithm part,the advantages and disadvantages of two kinds of position estimation algorithms based on Time Difference of Arrival,Chan algorithm and Taylor series expansion algorithm,are analyzed,and evaluates the positioning effect under different influence condition.In this paper,the two algorithms are combined,and the estimated value of Chan algorithm is used as the initial value of Taylor algorithm,which reduces the limitation of Taylor algorithm.Then,the two algorithms of weighting coefficient fusion are calculated according to the estimated position deviation of the two algorithms.It has the advantages of small calculation of Chan algorithm and high accuracy and robustness of Taylor algorithm.As the simulation experiment of the algorithm shown,the improved algorithm is better than the former two in positioning accuracy.Finally,this paper realized the indoor positioning application based STM32 and DWM1000 communication chip.This application gets the TDOA information measured by the DWM1000 positioning chip,uses collaborative algorithm programed by Matlab to estimate TDOA information and achieves the positioning coordinates.The experimental show that the system designed in this paper can achieve positioning and has a good positioning performence.At the end of the article,At the end of the paper,the deficiencies of the design and the need for improvement are analyzed and summarized,and the future research content is discussed. |
PDF Full Text Request