Indoor Positioning System Based On Received Signal Strength Indicator

With the development of economy and society,science and technology have developed rapidly,elderly services are also increasingly integrated with science and technology.Aging is a common topic in the world,due to the change of elderly services circumstances and the old people’s methods for themselves,the number of old people who are living alone or entering nursing homes is increasing.It has become a challenge for intime finding and providing care services for the elderly in reason when the unpredictable accident happened in the house of the frail elderly in today’s society.The lack of guardianship staff,the incomprehensive guardianship mode,and the excessively traditional guardianship system have been unable to adapt to the development of modern society.When the aged care service meets a new generation of computer technology,a smart aged care system comes into being.Aiming at the current needs of nursing care for the elderly in nursing homes,this paper provides the design and implementation of the monitoring system.Considering the requirements of intelligence and convenience,streamlined system,strong practicability,and convenient operation,the elderly who sit in wheelchairs are the monitoring objects.Relying on wireless communication and sensor technology,etc.,the elderly’s indoor location information and indoor environment are token as the monitoring content to design the monitoring system.The route of this work includes the system hardware design,software development,algorithm optimization and the design of host computer.The guardian can check the information through the system to obtain the living conditions of the elderly in the room and effectively assist the guardianship.In this article,our research work mainly includes the following five parts:1.Research on status analysis and design plan determination.It is determined to use wireless communication technology combined with sensor technology and host computer technology to design the system to obtain the elderly’s position information and indoor environmental values to achieve monitoring elderly purpose by summarizing and analyzing the current needs of elderly care in the society,the functions of existing monitoring systems,technical routes and other aspects.2.Hardware design and construction of each module of the monitoring system.Correctly select hardware chips and modules such as Zig Bee and Wi Fi,design corresponding functional circuits,combine the existing hardware resources of each module to make a reasonable electrical connection,and ensure the realization of the overall hardware function and stable and reliable work.3.Slave computer software design.Performing functional program configuration on the electrically connected pins to drive the module.Designing the STM32 program to drive the sensor workflow to complete the detection.Using the Zig Bee protocol stack,calling the corresponding API function to implement Zig Bee networking and data transmission and reception.Studying the TCP / IP protocol and AT commands to design the program and configure the Wi Fi module connection and transmission methods.Software design ensures modules can work well.4.Optimization of positioning algorithm and design of master computer.Collecting data reasonably,optimizing the commonly used ranging weighted geometric positioning algorithm to improve the positioning accuracy of the elderly.Developing Python code to achieve data acquisition and algorithm processing.Designing browser webpage and Python-based back-end server,studying Web Socket protocol to complete Web Socket communication between them,and finally realizing PC / mobile browser web access to the positioning display interface.5.Select environment and conduct a system test.Layout beacon nodes reasonably then test and verify whether the system achieves the expected reasonable guardianship goal.The test result shows that the system can realize the auxiliary monitoring function and the system is stable and convenient.The detection of indoor environment is reliable,and the positioning accuracy is high.It can also assist the monitoring of the elderly’s indoor daily life without disturbing the elderly’s life or invading privacy.It has important and positive significance for the elderly care industry,especially for the construction of smart elderly services.