With development of communications technologies, a positioning service is widely used. When a user requests the positioning service, a server needs to obtain location information of a terminal corresponding to the user and send the obtained location information to the terminal corresponding to the user. For example, path navigation is a positioning service, and when a user requests the path navigation, a server needs to obtain location information of a terminal corresponding to the user and send the obtained location information to the terminal corresponding to the user.
Currently, a method for obtaining location information is provided in the prior art, including: sending, by a to-be-positioned terminal, a sounding reference signal and a terminal identity to multiple base stations that cover the to-be-positioned terminal; after receiving the sounding reference signal and the terminal identity that are sent by the terminal, separately calculating, by all base stations in the multiple base stations, their respective corresponding signal features according to the sounding reference signal, where the signal feature includes at least a base station identity of a base station, a signal power, and signal transmission time; sending, by all the base stations, their respective corresponding signal features and the terminal identity to a positioning server; and receiving, by the positioning server, the signal features and the terminal identity that are sent by all the base stations, combining all received signal features into a signal feature set, obtaining, according to the signal feature set and from a correspondence between a signal feature set and location information, corresponding location information, and then sending the location information to the terminal according to the terminal identity.
Before the obtaining location information, the correspondence between a signal feature set and location information is first stored in the positioning server by performing the following operations, which are specifically as follows: A person skilled in the art divides a wireless coverage area into several equal-sized areas, and determines location information corresponding to each area; then, for each of the areas, a person skilled in the art brings a measured terminal to the area, and sends, by using the measured terminal, a sounding reference signal to multiple base stations that cover the measured terminal; all base stations in the multiple base stations respectively obtain their respective corresponding signal features according to the received sounding reference signal; all base stations send their respective corresponding signal features to the positioning server; and the positioning server receives the signal features sent by all the base stations, combines all the received signal features into a signal feature set corresponding to the area, and stores the signal feature set corresponding to the area and location information corresponding to the area in the correspondence between a signal feature set and location information. Similarly, for each of other areas, a signal feature set and location information that are of each of the other areas may be stored in the positioning server according to the foregoing operations.
In a process of implementing the present disclosure, the prior art has at least the following disadvantage:
The signal power included in the signal feature is related to a transmit power of a terminal. Because transmit powers of the measured terminal and the to-be-positioned terminal are different, a signal feature corresponding to the sounding reference signal sent by the to-be-positioned terminal and a signal feature corresponding to the sounding reference signal sent by the measured terminal are extremely different. Therefore, there is a great error in obtained location information when the location information is obtained according to the signal feature corresponding to the sounding reference signal sent by the to-be-positioned terminal.
USPTO Backgrounds
USPTO Backgrounds