Abstract: A telecommunications system comprises a first transmitter unit situated at a first, known location; a second transmitter unit situated at a second, unknown location; a first receiving unit at a third, known location arranged to receive signals from the first and second transmitter units; and a second receiving unit at a fourth, known location arranged to receive signals from the first and second transmitter units, wherein the said signals received by the first and second receiving units are usable to ascertain the location of the second transmitter unit.

Abstract: A method and system for compiling neighbour lists in a mobile communication network is described. A test signal is transmitted from one base station (BTS) to a set of location measurement units (LMU), one LMU preferably being associated with the transmitting BTS. The received signal is time stamped at each LMU and the transmission times calculated from the time stamps. The transmission times are compared and the list is compiled from those LMUs with close or the same transmission times.

Abstract: A method of providing information regarding a location of a mobile user of a communication system is provided. The method comprises a step of performing measurement for provision of input data for a location calculation function. The method includes a step of analyzing the measurements to identify suspicious measurements. The method also comprises a step of deciding selected measurements for use by the location calculation function. The method also includes a step of calculating a location estimate for a mobile user based on the selected measurements.

Abstract: A method and system for compiling neighbour lists in a mobile communication network is described. A test signal is transmitted from one base station (BTS) to a set of location measurement units (LMU), one LMU preferably being associated with the transmitting BTS. The received signal is time stamped at each LMU and the transmission times calculated from the time stamps. The transmission times are compared and the list is compiled from those LMUs with close or the same transmission times.

Abstract: A method and system for estimating the location of a mobile station in a telecommunications network having a reference base station and a plurality of neighboring base stations. At the beginning of the E-OTD measurement, the mobile station may be provided with the expected OTD values in the reference base station site, possibly instead of RTD values of the neighboring base stations, to make it possible for the mobile station to calculate the uncertainty in the measured OTD due to its unknown location. Alternatively, the network provides the mobile station the expected OTD values in its current location, and the estimated uncertainty of those values. When the uncertainty is greater than a predetermined value, the mobile station makes E-OTD measurements based on the SCH burst. Otherwise, the mobile station makes measurements based on normal/dummy bursts, and/or aligns the time window for taking samples from signals received from neighboring base stations.

Abstract: The invention relates to a method for determining transmission times of signals transmitted by at least one radio transmitter BTS. In order to enhance the accuracy and reliability of estimates of transmission times or of changes of the transmission time of signals transmitted by radio transmitters BTS, it is proposed that a difference in the time level of estimates of the transmission times based on the measurement results of two different radio receivers LMU A,B is taken into account in a filtering of the estimates for obtaining an accurate value for the transmission times. It is further proposed that the changes of the transmission times estimated at different receivers LMU A,B is averaged for obtaining an accurate information about the changes. The invention equally relates to a corresponding radio communications system and to a processing unit for such a system.

Abstract: The present invention relates to provision of location information concerning a wireless station of a communication system. In accordance with the method, at least one location measurement is accomplished by an element that associates with the communication system. An estimate for the location of the wireless station is defined based on the at least one measurement. The estimate is subjected to a non-linear measurement error minimisation routine to determine more accurate location of the wireless station.

Abstract: A method and system for estimating the location of a mobile station in a cellular radio network having a reference base station and a plurality of neighboring base stations capable of communicating with the mobile station. At the beginning of the E-OTD measurements, the mobile station may be provided with the expected OTD values in the reference base station site, possibly instead of RTD values of the neighboring base stations, in order to make it possible for the mobile station can calculate the uncertainty in the measured OTD due to the unknown location of the mobile station. In an alternative scenario the network provides the mobile station the expected OTD values in the current location of the mobile station, and the estimated uncertainty of those values. When the uncertainty is greater than a predetermined value, the mobile station makes the E-OTD measurements based on the SCH bursts.