I have done a search online to understand how to convert ECI to ECEF. I wanted to learn what the conversion is so I could just create a matlab script to make it happen. My problem is that most of the information I find assumes you already have some knowledge about ECI and ECEF. If I had more time I am confident I could learn about each system, make sense of the knowledge found all over the web and construct my own script.(adsbygoogle = window.adsbygoogle || []).push({});

My ultimate goal is to go from ECI to ENU. There are matlab toolboxes that can make this easy however I do not have access to those tool boxes so I must create my own.

Step 1: Convert ECI to ECEF. I want to take Matrix A which is in ECI and convert it to matrix A' which is in ECEF. So A'=eci2ecef(A).

Having limited knowledge I would like to know the direct formula (that is explained step by step if possible).

Step 2: Convert ECEF to ENU. Matrix A''=ecef2enu(A'). Maybe there is a way to go from ECI directly to ENU, that would be great but from what I have been reading it does not appear to be the case.

Any help would greatly be appreciated. If you require more information from me please just ask. I cannot yet think of how I can make this question better for those who come across it.

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# Convert ECI to ECEF

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