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 substracted 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 substraction steps are iterated until no useful signals remain to be extracted. <IMAGE>