The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 24, 2009
Filed:
May. 13, 2003
Peter James Duffett-smith, Cambridge, GB;
Malcolm David Macnaughtan, Sydney, AU;
John Christopher Clarke, Cambridge, GB;
Robert Willem Rowe, Villefranche, FR;
Peter James Duffett-Smith, Cambridge, GB;
Malcolm David Macnaughtan, Sydney, AU;
John Christopher Clarke, Cambridge, GB;
Robert Willem Rowe, Villefranche, FR;
Cambridge Positioning Systems Limited, Cambridge, GB;
Abstract
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 devicefor each transmitter, which sends to the computing devicea representation of the signals transmitted only by that transmitter. A cross-correlation of the representation sent back by the mobile terminalwith the representation sent back by the sampling device in the brightest transmitter is performed in the computing device, and a blurred estimate of that brightest signal is subtracted from a blurred version of the representation sent back by the mobile terminalin 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.