Cellguide Ltd. Patent applications |
Patent application number | Title | Published |
20120062426 | MULTIPATH MITIGATION IN POSITIONING SYSTEMS - The location of a receiver is determined by receiving respective ranging signals from each of a plurality of transmitters at known locations. The ranging signals are cross-correlated with respective model signals to provide respective cross-correlation functions. For cross correlation functions that are determined to include multipath noise, the multipath noise is estimated and removed. Respective delays of the cross-correlation functions are estimated and the location of the receiver is inferred from the delays. | 03-15-2012 |
20110234455 | GNSS NAVIGAGTION AIDED BY STATIC DATA - A GNSS receiver includes a RF front end for receiving GNSS ranging signals, a navigation processor for calculating location from the ranging signals, and a repository of static data. The navigation processor includes the static data in the location calculation. Examples of static data include a digital elevation map, coordinates of tunnel entrances for use when the receiver resumes reception of the signals upon exiting a tunnel, and descriptions of structures in sufficient detail to enable multipath mitigation. | 09-29-2011 |
20110219009 | METHOD OF GENERATING AN ELEVATION DATABASE - A method of generating an elevation database for selected geographic regions, the method comprising: receiving a location database, a rule database, and an input elevation database, each location in the location database being located within a selected geographic region; constructing, for each location in the location database and using rules from the rule database, a bounding region enclosing a continuous geographic region; applying elevation data from the input elevation database to each bounding region; and compressing the elevation data in each bounding region to provide compressed elevation data; wherein, upon decompressing the compressed elevation data, each point in each bounding region represents a level of elevation at that point in the associated selected geographic region. | 09-08-2011 |