Apparatus and method for use in global position measurements

Abstract

Embodiments of the invention involve providing assistance data to a global position and navigation receiver, for example topographical data, such that the receiver can decide on a specific action depending on that data. The topographical data may include one or both of geographical data and architectural data. Geographical data may include information about natural formations, such as hills, valleys, forests, etc. Architectural data may include manmade formations, such as streets, buildings, bridges, etc. The receiver may then interpret and decide on a course of action for controlling the receiver base on the assistance data.

1 . (canceled) 
     
     
         2 . A receiver comprising:
 a receiver controller configured to receive at least first, second and third satellite signals from first, second and third satellites above a horizon, the first, second and third satellite signals comprising global positioning information, the receiver controller further configured to access assistance data, the assistance data comprising one or more manmade architectural features and altitude data; and   when the receiver controller predicts that the one or more manmade architectural features will increase the length of the first satellite signal with multipath reflections that effect the estimated position of the receiver controller, the receiver controller is configured to reduce power consumption by not searching for the first satellite signal from the first satellite that is above the horizon, the receiver controller further configured to determine location based at least on the combination of the second satellite signal, the third satellite signal and the altitude data.   
     
     
         3 . The receiver of  claim 2  wherein when the receiver controller predicts that the one or more manmade architectural features will the cause multipath reflections, the receiver controller is configured to guide a user on a path that is less affected by the one or more manmade architectural features. 
     
     
         4 . The receiver of  claim 2  wherein the receiver controller predicts which ones of the one or more manmade architectural features will cause multipath reflections. 
     
     
         5 . The receiver of  claim 2  wherein when the receiver controller predicts that the one or more manmade architectural features will the cause multipath reflections, the receiver controller is configured to predict the magnitude of the effect on the estimated position of the receiver. 
     
     
         6 . The receiver of  claim 2  wherein when the receiver controller predicts that the one or more manmade architectural features will the cause multipath reflections in the first satellite signal, the receiver controller is configured to search for the second and third satellite signals. 
     
     
         7 . The receiver of  claim 2  wherein the assistance data further comprises topographical aspect of an area local to the receiver. 
     
     
         8 . The receiver of  claim 2  wherein the assistance data further comprises at least one of data pertaining to at least one architectural feature in an area local to the receiver and data pertaining to at least one geographical feature in the area local to the receiver. 
     
     
         9 . The receiver of  claim 2  wherein the assistance data further comprises for an area local to the receiver at least one of the group consisting of: a width of at least one street, an orientation of at least one street, data indicative of a property of materials of at least one topographical feature, and data indicative of a change in elevation. 
     
     
         10 . The receiver of  claim 2  wherein the receiver controller is further configured to enable the receiver to search for a fourth satellite signal when the receiver controller predicts that the one or more manmade architectural features will not cause the multipath reflections of the fourth satellite signal. 
     
     
         11 . The receiver of  claim 2  wherein the receiver controller is further configured to reduce processing power to allow more processing power for cell phone functions. 
     
     
         12 . A method to use in a receiver, the method comprising:
 receiving, with a receiver controller, first, second and third satellite signals from first, second and third satellites above a horizon, the first, second and third satellite signals comprising global positioning information;   accessing, with the receiver controller, access assistance data, the assistance data comprising one or more manmade architectural features and altitude data;   when the receiver controller predicts the one or more manmade architectural features will increase the length of the first satellite signal with multipath reflections that effect the estimated position of the receiver controller, the receiver controller reduces power consumption by not searching for the first satellite signal from the first satellite that is above the horizon, and determines location based at least on the combination of the second satellite signal, the third satellite signal and the altitude data.   
     
     
         13 . The method of  claim 12  wherein when the receiver controller is configured to predict that the one or more manmade architectural features will the cause multipath reflections, the receiver controller guides a user on a path that is less affected by the one or more manmade architectural features. 
     
     
         14 . The method of  claim 12  wherein the receiver controller predicts which ones of the one or more manmade architectural features will cause multipath reflections. 
     
     
         15 . The method of  claim 12  wherein when the receiver controller predicts that the one or more manmade architectural features will the cause multipath reflections, the receiver controller predicts the magnitude of the effect on the estimated position of the receiver. 
     
     
         16 . The method of  claim 12  wherein when the receiver controller predicts that the one or more manmade architectural features will the cause multipath reflections in the first satellite signal, the receiver controller searches for the second and third satellite signals. 
     
     
         17 . The method of  claim 12  wherein the assistance data further comprises topographical aspect of an area local to the receiver. 
     
     
         18 . The method of  claim 12  wherein the assistance data further comprises at least one of data pertaining to at least one architectural feature in an area local to the receiver and data pertaining to at least one geographical feature in the area local to the receiver. 
     
     
         19 . The method of  claim 12  wherein the assistance data further comprises for an area local to the receiver at least one of the group consisting of: a width of at least one street, an orientation of at least one street, data indicative of a property of materials of at least one topographical feature, and data indicative of a change in elevation. 
     
     
         20 . The method of  claim 12  wherein the receiver controller is further configured to enable the receiver to search for a fourth satellite signal when the receiver controller predicts that the one or more manmade architectural features will not cause the multipath reflections of the fourth satellite signal. 
     
     
         21 . The method of  claim 12  wherein the receiver controller is further configured to reduce processing power to allow more processing power for cell phone functions.