I agree with Vitaly : TEMS logfiles are heavily encrypted, so nobody can post-process them directly. What you need to do is us the “Export Logfile” function of TEMS. TEMS allows you to translate the logfile in the text format of your choice.
You can even filter out the measurements you don’t need, and keep only the data you need (for instance, for basic GSM traces : Serving cell RxLev, RxQual, Long/Lat, Neighbours RxLev, etc…)
All docs about TEMS software can be found on http://www.ericsson.com.