Mr. Wallis , i am very much thankful for your response..
Here i would like to add some more info..The Redmi Note4 can neither latch to GSM (Nortel) , Nor to GSM/WCDMA (Ericsson)in my area..
Being a novice i did not understand when you said Radio stack of Note4..Do you mean the range of frequencies on which the note4 can operate ?
What functionalities can those patches add to the network ? Should they be deployed in BSC,Media Gateway , GMSC or in IN ?
With thanks in advance