= Navigation Processing =

The first step of processing a project is to do process the GPS and Inertial Measurement Unit (IMU) data.

== PosPAC ==

This is the procedure used for data processing from 2021 with the aplanex system. The user manual is available on the [https://pmlacuk.sharepoint.com/:b:/s/NEODAAS/Ef7dqC-r1ZBKp_sGPtJj0UsBih8xyfGy5IsFB5UxX1yEPA?e=5xzLYa PML Sharepoint (internal access only)]




== IPAS TC ==

This was the procedure used for processing data up to 2019.

When using a basestation (standard procedure) the position must be verified first:

 1. [wiki:Processing/BasestationVerification Base station position verification]
 1. [wiki:Processing/IPASTC IPASTC Processing]

If IPAS TC does not give sufficiently high accuracy then we can use IPAS Pro + GrafNav to try and get an improved result. See [wiki:Processing/IPASTC#AnalysingtheData] for what is meant by "sufficiently high accuracy".

 * [wiki:Processing/IPASPro IPASPro Processing]

For data collected in 2012 onwards we can use the .sol files generated above directly in the hyperspectral processing software. There is no need to create SBET files.

=== Base station issues ===

For information on how to convert the NERC-ARF Leica basestation to RINEX data see '''[wiki:Processing/RawToRinex here]''

If there are no basestation data with the project then check '''[wiki:Processing/GNSSStatinons here]''' for possible places to download from.

If you find you need to do a Network Adjustment then look '''[wiki:Processing/NetworkAdjustment here]''' for instructions how.

For limited information on converting base station formats check this '''[wiki:Processing/RawToRinex page]'''.

For downloading Iceland basestations: '''[wiki:IcelandBasestations]'''.

=== Older instructions for pre 2012 ===

If you need to process navigation data for the hyperspectral instruments:

Due to problems with the applanix system in 2011, instead of processing the applanix navigation separately, we now convert the IPAS .sol generated above into an .sbet and use this, with appropriate changes to the boresight and lever arms. 

To convert, go into IPAS and click Tools -> File Converter.

The old applanix instructions are here:
 * [wiki:Procedures/ProcessingChainInstructions/auto_applanix Automatic Method]
 * [wiki:Processing/Applanix Manual Method]