Are you a GATE Electronics and Communications Engineering aspirant? Then this article is for you. Let’s get high on the GATE preparation for ECE focusing on control systems. Check out the syllabus, important topics and some good references to study this topic.

Control Systems Syllabus for GATE Electronics and Communications Engineering

Here is the latest syllabus for ECE Gate released by IIT Kharagpur:

S.No Sections Topics to be Covered

Engineering Mathematics

Linear AlgebraCalculus

Differential Equations

Vector Analysis

Complex Analysis

Numerical Methods

Probability and Statistics


Networks, Signals and Systems

Circuit analysisContinuous-time signals

Discrete-time signals


Electronic Devices

Energy bands in intrinsic and extrinsic semiconductors, equilibrium carrier concentration, direct and indirect band-gap semiconductors.

Carrier transport: diffusion current, drift current, mobility and resistivity, generation and recombination of carriers, Poisson, and continuity equations. P-N junction, Zener diode, BJT, MOS capacitor, MOSFET, LED, photodiode, and solar cell.


Analog Circuits

Diode circuits: clipping, clamping, and rectifiers.

BJT and MOSFET amplifiers: biasing, ac coupling, small-signal analysis, frequency response. Current mirrors and differential amplifiers.

Op-amp circuits: Amplifiers, summers, differentiators, integrators, active filters, Schmitt triggers, and oscillators


Digital Circuits

Number representations: binary, integer, and floating-point- numbers.

Combinatorial circuits: Boolean algebra, minimization of functions using Boolean identities and Karnaugh map, logic gates, and their static CMOS implementations, arithmetic circuits, code converters, multiplexers, decoders.

Sequential circuits: latches and flip-flops, counters, shift-registers, finite state machines, propagation delay, setup and hold time, critical path delay.

Data converters: sample and hold circuits, ADCs, and DACs.

Semiconductor memories: ROM, SRAM, DRAM.

Computer organization: Machine instructions and addressing modes, ALU, data-path, and control unit, instruction pipelining


Control Systems

Basic control system components; Feedback principle; Transfer function; Block diagram representation; Signal flow graph; Transient and steady-state analysis of LTI systems; Frequency response; Routh-Hurwitz and Nyquist stability criteria; Bode and root-locus plots; Lag, lead and lag-lead compensation; State variable model and solution of state equation of LTI systems.



Random processes: autocorrelation and power spectral density, properties of white noise, filtering of random signals through LTI systems.

Analog communications: amplitude modulation and demodulation, angle modulation and demodulation, spectra of AM and FM, superheterodyne receivers.

Information theory: entropy, mutual information, and channel capacity theorem.

Digital communications: PCM, DPCM, digital modulation schemes (ASK, PSK, FSK, QAM), bandwidth, inter-symbol interference, MAP, ML detection, matched filter receiver, SNR, and BER.

Fundamentals of error correction, Hamming codes, CRC.



Maxwell’s equations: differential and integral forms and their interpretation, boundary conditions, wave equation, Poynting vector.

Plane waves and properties: reflection and refraction, polarization, phase and group velocity, propagation through various media, skin depth.

Transmission lines: equations, characteristic impedance, impedance matching, impedance transformation, S-parameters, Smith chart.

Rectangular and circular waveguides, light propagation in optical fibers, dipole and monopole antennas, linear antenna arrays.

Important Topics to Cover for GATE Preparation for ECE

Now we will move on to look at the important topics that should be well studied in control systems while preparing for GATE.

Also Read: Preparing to Apply for GATE 2021? Know The Eligibility Criteria for GATE Exam

#1. Transfer Function

Block Diagram reduction technique and equivalent Transfer Functions for both positive and negative feedback are important for GATE preparation for ECE. Signal Flow Graphs and Mason’s Gain Formula’s help simplify problems here.

#2. Time Domain Analysis

Time response of 2nd order system, time response specifications and steady-state error are considered important. Formulas for rise-time, maximum overshoot, settling time, peak time and also various error coefficients like position error coefficient, velocity error coefficient and acceleration error coefficient are important.

#3. Time Domain Stability

Routh’s stability criterion and root locus (complimentary root locus) are important topics.

#4. Frequency Domain Analysis

Formulas of resonant frequency, resonant peak and bandwidth should be remembered. Frequency response and bode plots are important.

#5. Polar & Nyquist Plots

Gain and phase margin.

#6. State Variable Analysis

Model from transfer function, the transfer function from state model, solution of state equation, controllability observability and stability of a system are important. The transition matrix and its relation with the transfer function should be known.

#7. Controllers

PD controller, Pi controller and PID controller are important.

#8. Compensator

Lead compensator, Lag compensator and Lead-Lag compensator are important here.

Good Resources for GATE Exam Preparation

# Automatic Control Systems by B.C. Kuo

# Control System Engg. by I.G. Nagrath & M.Gopal

# Linear Control System by B.S. Manke

Study Strategy for GATE preparation for ECE

# Make a study strategy and study the topics in sequence. Make notes while studying.

# Give more time to important topics like electronics devices, digital circuits etc.

# While preparing for GATE, solve problems after finishing every topic.

# Understand the strong and weak areas in that topic.

# So,  you have ample time, read the concepts of the weak topic again (ask a friend or professor for help if needed). If short on time, first check if the topic that you are weak in is listed in the list of the important topics. If not mark it, and skip it for now. Come back to it later, after you have completed the entire syllabus and are left with time to study that topic.

# Also, repeat the same for all the subjects.

# After finishing all, solve full portion practice tests dedicated for GATE preparation for ECE.

# Furthermore, analyse your results from there. First target the topics that hold high weightage and you are weak at.

# Repeat the previous step till before GATE.

Extra Tips for GATE Exam Preparation

While you may take your time to decide for yourself, have a look at a video on Classical Control Theory by one of the faculty at GATE School. Also, At GATE School students are offered video lectures, personalised mentor support to every student who enrols for the course and ample tests.


So, If you are in a time crunch it may be a good idea to consider hiring a personal tutor or joining an online course to help you save time in understanding concepts and clearing doubts. Hence,  should help you analyse your test result and help you get personalized guidance. Best of luck with your exam!

Also Read: What are good habits every GATE aspirant must adapt?