You can consider below reference books -

Integrated electronics: Analog and Digital Circuit and system - Jacob Millman & Halkias

Communication System - Simon Haykins

Signal and System - Oppenheim and Willsky

Satellite Communications - Pratt and Bostian

Monochrome and colour - R.R. Gulati

Control System Engg. - I.G. Nagrath

Elements of Engineering Electromagnetics - N. N. Rao

Digital Design - M. Morris Mano

Microprocessor Architecture, Programming & Application - Ramesh S. Gaonkar

Microwave Devices and Circuits - Liao

Networks and Systems - D. Roy Chaudhary

Electrical & Electronic Measurement and Instrumentation - A. K. Sahney

Good Luck!!!