Goal: Write a Matlab function to compute the elevation angle of a GPS satellite with respect to the given receiver location. Why? The elevation angle of a satellite is useful to know when you are trying to understand the different error sources in GPS.

1. Cartesian station location (m):
     -1283387.6627
     -4713015.5351
     4090190.4704
   

2. Cartesian satellite location for PRN 24 (m):
     X = -11918707.0438537
     Y = -23755879.2115591
     Z = -75141.8219498
   

1. Your main code should define XYZ for satellite and receiver.

2. Convert receiver XYZ to lat/long/height.

3. Compute the local up unit vector for the receiver:

   

   where and are latitude and longitude.

4. Compute the vector that points from the receiver to the satellite.

5. You should now send both the vectors (up vector and the vector that points from the receiver to the satellite) to a function to compute the elevation angle. In the elevation angle function:
   • Compute the angle between the two vectors. This angle is called the zenith angle. Dig out your calculus book, and remind yourself how the dot product can be used to determine the angle between two vectors.

   • Compute the elevation angle. Elevation angle is defined (in degrees): elevation angle = 90 - zenith angle. Graphically, elevation angle is the angle with respect to the local horizon.

6. Have your code check to see that the elevation angle is negative. If it is, print out a warning.

7. Print out elevation angle in degrees, to 4 decimal places.

Turn in: all new code (i.e. I don't need to see the lat/long/height code again).