Geodesy with the Global Positioning System

EESC G9945 Section 2

Spring Term 2013

Term Project Subgoal 2 Information

Due date: 8 March 2013

Background

In the second step in our position estimator, we will use the results from the first step to calculate the cartesian coordinates for the satellites at any epoch during the day. As before, please do not hesitate to e-mail me or stop by (quicker response) if you have questions or are having difficulties. Also, if you have not completed the first part of the project you should be able to wrap that up at the same time as this part. You will need to be able to calculate accurate satellite positions at an arbitrary epoch for the next part of the project.

Navigation data

You will use the same navigation data file as for the first part of the project.

Suggested program structure

1. Read the navigation file. Completed in Subgoal 1.
2. For each target epoch and target PRN (see below) identify the closest TOE in the navigation data. This is similar to what you did in Subgoal 1.
3. Calculate Earth-fixed Cartesian satellite coordinates. Given a target epoch and the pointer from (2), calculate the Cartesian Earth-fixed coordinates of the satellite at the observation epoch using the formulas given in the class notes.

Target epochs and PRNs

For PRNs 1, 8, 13, and 23, print the Earth-fixed Cartesian coordinates at 15 minute intervals between 2008/04/09 4:00:00.0 and 5:00:00.0 (inclusive). Use the same output format as for Subgoal 1.

What to send me:

E-mail the results of your program by 5 PM on the due date.