[Galaxy S 5 Q&A, Help & Troubleshooting] one-option:
I got an answer from SamMobile

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hello

sorry but no 4G for Iran at this time

latest Samsung 4G MEA (Middle East Arabic) list:

<!-- MEA -->

<whiteLists numeric="42001" ltestate="PS/CSFB" operator="STC" country="SAUDI" defaultMode="GWL"/>

<whiteLists numeric="42003" ltestate="PS/CSFB" operator="MOBILY" country="SAUDI" defaultMode="GWL"/>

<whiteLists numeric="42004" ltestate="PS/CSFB" operator="ZAIN" country="SAUDI" defaultMode="GWL"/>

<whiteLists numeric="42402" ltestate="PS/CSFB" operator="Etisalat" country="UAE" defaultMode="GWL"/>

<whiteLists numeric="42403" ltestate="PS/CSFB" operator="du" country="UAE" defaultMode="GWL"/>

<whiteLists numeric="41902" ltestate="PS/CSFB" operator="Zain" country="Kuwait" defaultMode="GWL"/>

<whiteLists numeric="41903" ltestate="PS/CSFB" operator="Wataniya" country="Kuwait" defaultMode="GWL"/>

<whiteLists numeric="41904" ltestate="PS/CSFB" operator="Viva Kuwait" country="Kuwait" defaultMode="GWL"/>

<whiteLists numeric="41501" ltestate="PS/CSFB" operator="Alfa" country="Lebanon" defaultMode="GWL"/>

<whiteLists numeric="41503" ltestate="PS/CSFB" operator="MTC-Touch" country="Lebanon" defaultMode="GWL"/>

<whiteLists numeric="42202" ltestate="PS/CSFB" operator="Omantel" country="Oman" defaultMode="GWL"/>

<whiteLists numeric="42203" ltestate="PS/CSFB" operator="nawras" country="Oman" defaultMode="GWL"/>

<whiteLists numeric="42501" ltestate="PS/CSFB" operator="Orange" country="Israel" defaultMode="GWL"/>

<whiteLists numeric="42502" ltestate="PS/CSFB" operator="Cellcom" country="Israel" defaultMode="GWL"/>

<whiteLists numeric="42503" ltestate="PS/CSFB" operator="Pelephone" country="Israel" defaultMode="GWL"/>

<whiteLists numeric="42601" ltestate="PS/CSFB" operator="Batelco" country="Bahrain" defaultMode="GWL"/>

<whiteLists numeric="42602" ltestate="PS/CSFB" operator="Zain" country="Bahrain" defaultMode="GWL"/>

<whiteLists numeric="42604" ltestate="PS/CSFB" operator="Viva Bahrain" country="Bahrain" defaultMode="GWL"/>

<whiteLists numeric="42701" ltestate="PS/CSFB" operator="Ooredoo" country="Qatar" defaultMode="GWL"/>

<whiteLists numeric="42702" ltestate="PS/CSFB" operator="vodafone" country="Qatar" defaultMode="GWL"/>

<whiteLists numeric="61203" ltestate="PS/CSFB" operator="Orange" country="Ivory Coast" defaultMode="GWL"/>

<whiteLists numeric="61701" ltestate="PS/CSFB" operator="Orange" country="Mauritius" defaultMode="GWL"/>

<whiteLists numeric="61710" ltestate="PS/CSFB" operator="EMTEL" country="Mauritius" defaultMode="GWL"/>

<whiteLists numeric="63102" ltestate="PS/CSFB" operator="Unitel" country="Angola" defaultMode="GWL"/>

<whiteLists numeric="64502" ltestate="PS/CSFB" operator="MTN" country="Zambia" defaultMode="GWL"/>

<whiteLists numeric="64901" ltestate="PS/CSFB" operator="MTC" country="Namibia" defaultMode="GWL"/>

<whiteLists numeric="65501" ltestate="PS/CSFB" operator="Vodacom" country="South Africa" defaultMode="GWL"/>

<whiteLists numeric="65510" ltestate="PS/CSFB" operator="MTN" country="South Africa" defaultMode="GWL"/>

regards

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ok that mean Samsung should update the 4G providers and add Iran to the list.