Abstract: This invention relates to a method for mapping Wi-Fi fingerprints in a given geographical area. A user, provided with a receiver, sequentially collects Wi-Fi signal strength measurements by moving along the path thereof, with each measurement being constituted by a vector of RSS levels received from the various Wi-Fi access points. A graph that is representative of the path is determined from the sequence of measurements. Thanks to a geometric model of the area, a topographical characterization of the path is carried out on the basis of the previously obtained graph. The positions of the various measurements of the sequence are provided by the topographical characterization and stored with said measurements in a database.

Abstract: This invention relates to a method for mapping Wi-Fi fingerprints in a given geographical area. A user, provided with a receiver, sequentially collects Wi-Fi signal strength measurements by moving along the path thereof, with each measurement being constituted by a vector of RSS levels received from the various Wi-Fi access points. A graph that is representative of the path is determined from the sequence of measurements. Thanks to a geometric model of the area, a topographical characterisation of the path is carried out on the basis of the previously obtained graph. The positions of the various measurements of the sequence are provided by the topographical characterisation and stored with said measurements in a database.

Abstract: A method for positioning a terminal using signals received from a plurality of access points of at least one wireless telecommunications network is disclosed. According to some aspects, the terminal first retrieves identifiers of the access points from the received signals, then searches in a first database (BDP) for respective geographical position information for the access points. A first estimation of a position of the terminal or a positioning zone of the terminal is obtained from geographical position information of the access points, then topographical information corresponding to the first estimation of the position or the positioning zone is retrieved from a second database (SIG). A second estimation of the position of the terminal is performed using the topographical information thus obtained.

Abstract: A method for positioning a terminal using signals received from a plurality of access points of at least one wireless telecommunications network is disclosed. According to some aspects, the terminal first retrieves identifiers of the access points from the received signals, then searches in a first database (BDP) for respective geographical position information for the access points. A first estimation of a position of the terminal or a positioning zone of the terminal is obtained from geographical position information of the access points, then topographical information corresponding to the first estimation of the position or the positioning zone is retrieved from a second database (SIG). A second estimation of the position of the terminal is performed using the topographical information thus obtained.

Abstract: The invention provides a communications system having a novel multi-frame signal format. Frequency correction information is transmitted in a time slot of a frame immediately preceding a timeslot in which synchronization information is transmitted. The invention allows faster synchronization to a cell in the communication system.