首页>
外国专利>
TECHNIQUES BASED ON MOBILE-SUPPORTED NETWORKS TO IMPROVE THE ACCURACY OF WIRELESS POSITIONING SYSTEMS
TECHNIQUES BASED ON MOBILE-SUPPORTED NETWORKS TO IMPROVE THE ACCURACY OF WIRELESS POSITIONING SYSTEMS
展开▼
机译:基于移动支持网络的无线定位系统准确性提高技术
展开▼
页面导航
摘要
著录项
相似文献
摘要
The accuracy of the location estimate of a Wireless Location System is dependent, in part, upon both the transmitted power of the wireless transmitter and the length in time of the transmission from the wireless transmitter. In general, higher power transmissions and transmissions of greater transmission length can be located with better accuracy by the Wireless Location System than lower power and shorter transmissions. Wireless communications systems generally limit the transmit power and transmission length of wireless transmitters in order to minimize interference within the communications system and to maximize the potential capacity of the system. Several methods meet the conflicting needs of both systems by enabling the wireless communications system to minimize transmit power and length while enabling improved location accuracy for certain types of calls, such as wireless 9-1-1 (emergency) calls. Such methods include mobile-assisted techniques in which the mobile unit includes functionality to assist in improving location accuracy. The WLS locates the transmitter (mobile unit) while the latter is using a modified transmission sequence comprising a message sent from the wireless transmitter using transmission parameters different from the normal transmission parameters broadcast on the forward control channel by the base stations in the associated wireless communications system. A trigger event, such as the user dialing 9-1-1, causes the mobile unit to operate in the mode in which the modified transmission sequence is used.
展开▼