Is there any separate paper for applied electronics and instrumentation engineering students in GATE???

Yes there is separate paper for applied electronics and instrumentation engineering in GATE. Gate paper is common for all students. The code for the Instrumentation Engineering is IN.

Other GATE disciplines are as following:
GATE Paper Code
Aerospace Engineering AE
Agricultural Engineering AG
Architecture and Planning AR
Biotechnology BT
Civil Engineering CE
Chemical Engineering CH
Computer Science and Information Technology CS
Chemistry CY
Electronics and Communication Engineering EC
Electrical Engineering EE
Ecology and Evolution EY
Geology and Geophysics GG
Instrumentation Engineering IN
Mathematics MA
Mechanical Engineering ME
Mining Engineering MN
Metallurgical Engineering MT
Physics PH
Production and Industrial Engineering PI
Textile Engineering and Fiber Science TF
Engineering Sciences XE
Life Sciences XL