Method and apparatus for generating and distributing satellite tracking information

Abstract

A method and apparatus for generating and distributing satellite tracking data to a remote receiver is disclosed. The method for includes extracting from satellite-tracking data initial model parameters representing a current orbit of at least one satellite-positioning-system satellite, computing an orbit model using the initial model parameters, wherein a duration of the orbit model is longer than a duration of the satellite-tracking data, comparing, for an overlapping period of time, the orbit model to the satellite-tracking data; and adjusting the orbit model to match the satellite tracking data for the overlapping period of time so as to form an adjusted orbit model. The adjusted orbit model comprises the long-term-satellite-tracking data.

1 - 20 . (canceled) 
     
     
         21 . A method for generating customized satellite orbit data, the method comprising:
 measuring, at a tracking station, motion of a satellite over a measurement period;   calculating and storing satellite tracking data based on the measuring;   receiving a request, from a remote device, for customized satellite orbit data that specifies a desired orbit model and a desired time interval;   generating the customized satellite orbit data; and   transmitting the customized satellite orbit data to the remote device.   
     
     
         22 . The method of  claim 21 , wherein the desired time interval starts at a current time. 
     
     
         23 . The method of  claim 21 , wherein the desired time interval starts at a future time. 
     
     
         24 . The method of  claim 21 , wherein the calculating comprises:
 calculating an actual trajectory of the satellite over the measurement period;   extrapolating the actual trajectory of the satellite beyond the measurement period.   
     
     
         25 . The method of  claim 21 , wherein the desired orbit model is an ephemeris model specified by a global positioning system (GPS) standard. 
     
     
         26 . The method of  claim 21 , wherein the desired orbit model is a model specified by a GLONASS standard or a GALILEO standard. 
     
     
         27 . The method of  claim 21 , wherein the customized satellite orbit data is valid longer than ephemeris data broadcast from the satellite. 
     
     
         28 . The method of  claim 21 , wherein the measuring includes measuring code phase, carrier phase, or Doppler effect. 
     
     
         29 . The method of  claim 21 , wherein the generating comprises:
 retrieving the stored satellite tracking data for the desired time interval;   initializing parameters of the desired orbit model; and   adjusting the parameters based on the satellite tracking data for the desired time interval.   
     
     
         30 . The method of  claim 21 , wherein the transmitting comprises:
 determining a period of low data usage; and   transmitting the customized satellite orbit data during the period of low data usage.   
     
     
         31 . A system for generating customized satellite orbit data, the system comprising:
 a tracking station configured to measure motion of a satellite over a measurement period and to generate satellite tracking data based on the measured motion;   a database configured to store the satellite tracking data;   a distribution server configured to receive a request, from a remote device, for customized satellite orbit data that specifies a desired orbit model and a desired time interval and to generate the customized satellite orbit data; and   a transmitter configured to transmit the customized satellite orbit data to the remote device.   
     
     
         32 . The system of  claim 31 , wherein the desired time interval starts at a current time. 
     
     
         33 . The system of  claim 31 , wherein the desired time interval starts at a future time. 
     
     
         34 . The system of  claim 31 , wherein the tracking station is further configured to calculate an actual trajectory of the satellite over the measurement period and to extrapolate the actual trajectory of the satellite beyond the measurement period to generate the satellite tracking data. 
     
     
         35 . The system of  claim 31 , wherein the desired orbit model is an ephemeris model specified by a global positioning system (GPS) standard. 
     
     
         36 . The system of  claim 31 , wherein the desired orbit model is a model specified by a GLONASS standard or a GALILEO standard. 
     
     
         37 . The system of  claim 31 , wherein the customized satellite orbit data is valid longer than ephemeris data broadcast from the satellite. 
     
     
         38 . The system of claim  11 , wherein the measuring includes measuring code phase, carrier phase, or Doppler effect. 
     
     
         39 . The system of  claim 31 , wherein the distribution server is further configured to retrieve the stored satellite tracking data for the desired time interval from the database, to initialize parameters of the desired orbit model, and to adjust the parameters based on the satellite tracking data for the desired time interval in order to generate the customized satellite orbit data. 
     
     
         40 . The system of  claim 31 , wherein the transmitter is further configured to determine a period of low data usage and to transmit the customized satellite orbit data during the period of low data usage.