Research And Development Based On Key Technologies Of BLE Indoor Positioning

With the rapid development of wireless communication technology and computer field,people need more and more positioning requirements.But some environmental factors including shopping malls will creat a bad effect on the GPS positioning system signal transmission,which lead to poor positioning.And when the mine is in a deeper position under the ground,the signals of mobile phones and other wireless devices are too weak to achieve the desired positioning effect.Therefore this article aim to has a better positioning effect in these environments by analyzing these positioning scenes and conducting simulation test.Firstly,the paper compares the research background with the current research status of the current indoor positioning at home and abroad.Through illustrating and analyzing the advantages and disadvantages of current mainstream indoor positioning technology,the paper uses the Bluetooth 4.0 technology with low power consumption,anti-interference and long-distance as a system platform hardware.Then the essay introduces the Bluetooth 4.0 technology in detail,explores of the network and system structure of the Bluetooth and adopt a main multi-network approach.This is a effective prerequisite to establish the Ranging Model and Verification Location Algorithm.Secondly,the article adopts positioning method based on distance measurement.According to the indoor environment,the path loss model corresponding to the RSSI signal value is established.Because the collected RSSI signal value is easily disturbed by the indoor multiparth effect,the coarse error data or the random error data are generated.If the error data is not filtered accordingly,the distance measurement model is not accurate.And thus it has a crucial impact on the subsequent positioning.This paper uses the LADE test method combined with Kalman filter to filter the error data.Through the data analysis,the RSSI signal value after filtering is more accurate so that we can get an accurate path loss model.Finally,the paper designs a optimized weighted quadrilateral localization algorithm after theoretical analysis.Because there are some shortcomings in traditional weighted quadrilateral localization algorithm,the weight of this weighted value is analyzed and the optimal weighting parameter is obtained by verifying the experimental data.Based on the establishment of a more accurate path loss model,the corresponding test points are established in the room,and the data acquisition and location analysis are carried out by using the existing three-sided measurement method,the weighted centroid localization algorithm and the improved weighted quadrilateral localization algorithm.By analyzing the final positioning data,the final positioning results ensure that the improved indoor positioning algorithm in the practical application has a good effect.The positioning accuracy is less than 0.6 meters to meet the current indoor positioning requirements.