Here are some good booksyou can consider for clearing gate examination ece-
1. GATE 2018: Engineering Mathematics - By Madeeasy Publication.
2. Fundamentals of Digital Circuit by A Anand Kumar
3. Control System By BC Kau
4. Signal And System By Schaums
5. Networks and Systems By D. Roy Chaudhury.
6. GATE Electronics & Communication VOl-03 (Only for Practice Network and Signal System) by RK Kanodia
7. Principles of Electromagnetic By Saduku.
8. Fundamentals of Electric Circuits By Alexander Sadiku
9. Integrated Electronics(EDC) By Millman and Haljias
10. Electronic Circuit Analysis (Analog Electronics) and Design by Donald A. Neamen
11. Microprocessor by Ramesh Gaonkar
Hope this helps.
For Electronics & Communications Engineering (ECE), these are the books you should use for your preparations. Many of our experts in GATE recommend them and multiple candidates have tested these books by using in the exams.
Topic Book Author
Communications Modern Digital and Analog CommunicationsSystems B.P. Lathi
Signals & Systems Signals and Systems Alan V. Oppenheim, AlanS.Willsky, S.Hamid Nawab
Electronic Devices Semiconductor Physics and Devices Donald A. Neamen
Electromagnetic Theory Principles of Electromagnetics Matthew N. O. Sadiku
Control Systems Control Systems Engineering M. Gopal, I. J. Nagrath
Automatic Control Systems Benjamin Kuo
Digital Electronics Digital Design M. Morris Mano
Modern Digital Electronics R. P. Jain
Microprocessor Architecture, Programming and Applications with the 8085 Ramesh Gaonkar
Analog Circuits Microelectronic Circuits: Theory and Applications Adel S. Sedra, Kenneth Carless
Op-Amps & Linear Integrated Circuits Ramakant Gayakwad
Engg. Maths Higher Engineering Mathematics B. S. Grewal
GATE Engineering Mathematics: Multiple Choice Questions R. K. Kanodia
Network Theory Engineering Circuit Analysis William H. Hayt
Network Analysis Mac Van Valkenburg
Feel free to comment if you have any doubt