How to get ARFCN in Android 6.0( Marshmallow)

[mrajanna]

How can I use below implementation in Android 6.0 framework.

gsm.getCellIdentity().getArfcn();

I know above implementation is added in Android 7.0, but I am interested in adding this patch to 6.0.

For your Information: I don't want to upgrade Android to 7.0.

Thanks Mohan