Samsung has updated firmware for Samsung Galaxy Tab S 8.4 LTE on January 2015. This update which is automatically updated by the system has around 150 Mb in size. At fisrt i thought it was lollypop update, but after installation completed and reboot i didnt see any changes in UI. so i was expecting other kind of update, and violaa, after i checked my data connection, new menu appear. this menu now enable us to choose LTE data connection :).
With this update now we can use LTE data connection (if it is available) on our Samsung Galaxy Tab S 8.4. To update this firmware just do check system/software update from setting > general > about device > software update, choose update now or check automatic update if you want this system to do the updat automatically whenever the update is available. Thats it, enjoy your Samsung Galaxy Tab S 8.4 with faster (LTE) data connection :D.