Regular Expressions 101

Explanation
Pro

^start of line

Non-Capturing Group(?:LTE_LTE_)?

?repeats the group contents below at most once:

LTE_LTE_the literal text LTE_LTE_ (case sensitive)

Group 1(\S{7})

\S{7}any non-whitespace character, repeated exactly 7 times

\S*any non-whitespace character, repeated any number of times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^(?:LTE_LTE_)?(\S{7})\S*$

New

LTE_LTE_FSD9167__P_Airport1
RUR1251__S_KhooNaiWala

LTE_LTE_FSD9167__P_Airport1
RUR1251__S_KhooNaiWala