Improvements in radio positioning systems

摘要

The present invention sets out to overcome the hearability problem in CDMA communications networks in which positioning services are provided, by using a separate sampling device 204, 205, 206 for each transmitter 201, 202, 203, which sends to the computing device 208 a representation of the signals transmitted only by that transmitter. A cross-correlation of the representation sent back by the mobile terminal 207 with the representation sent back by the sampling device in the brightest transmitter is performed in the computing device 208, and an estimate of that brightest signal is subtracted from the representation sent back by the mobile terminal 207 in order to reduce its effect on the remaining signals as far as possible. The cross-correlation and subtraction steps are iterated until no useful signals remain to be extracted.