Research On Multiple Access Technology In Indoor Acoustic Positioning

In recent years, the application of indoor wireless location based on location service has been booming. But the existing indoor wireless positioning technology is limited by the hardware equipment and the use of the environment and other factors, and can not be a large-scale commercial applications. In this paper, we propose a new method of indoor acoustic space positioning technology based on two-way ranging method with the the mobile device terminal, and design a kind of weighted correction algorithm to correct the positioning results.Meanwhile, with simultaneous increase in the number of access devices, multiple-access capability of the system is increasingly becoming a bottleneck of restricting indoor sonar location. In order to improve the performance of multiple-access location system, we proposes a multiple access technology based on two variables Chirp combination signal. The multiple access technology can adjust the frequency difference between the chirp signal at small, rely on different initial phase to ensure orthogonality between multiple access signal..In order to effectively suppress the multiple access interference between different nodes, and significantly improve the address number of the positioning system.Finally,Use of Moble devices and Microcontrollers to build the indoor acoustic wave positioning system based on a combination of multiple access Chirp signal. Respectively, ranging and localization experiments is tested the performance of prototype system. The results show that the positioning accuracy of the indoor acoustic space positioning system can reach 91% when the precision error is 1 meter.