Digital Communication (BEC601) - AKTU Question Paper 2024-25
B.Tech · Semester 6 · Free PDF Download
This is the official AKTU Digital Communication Previous Year Question Paper for B.Tech Semester 6, academic session 2024-25. Published by Dr. A.P.J. Abdul Kalam Technical University (AKTU/UPTU), Lucknow. Free PDF download — no login required.
Course:B.Tech
Semester:Semester 6
Session:2024-25
University:AKTU / UPTU
Rate this paper
Questions Asked in 2024-25
Digital Communication (BEC601) — complete question paper · 70 marks · 3 Hours
Section AAttempt all questions in brief. 02 x 7 = 14
- aWhat is a random variable? How is it related to the concept of probability in communication systems?
- bWhat do you mean by the mean and variance of a random variable?
- cCompare PSK and FSK modulation techniques
- dWhat is a digital communication system? Mention any two advanta ges over analog communication systems
- eW h a t i s t h e e x p r e s s i o n f o r t h e B i t E r r o r R a t e ( B E R ) o f B i n a r y Phase Shift Keying (BPSK) in an AWGN channel?
- fList any two application of Direct Sequence Spread Spectrum (DS-SS) systems
- gWhat is meant by signal space representation of signals?
Section BAttempt any three of the following: 07 x 3 = 21
- aWhat do you understand by statistical averages? Explain all its properties
- bDescribe scrambler and unscrambler with the help of suitable diagram
- cExplain the working principles of ASK, FSK, and PSK modulation schemes with their constellation diagrams
- dExplain the basic principles of Spread Spectrum Communication. Discuss its two main types and their key characteristics
- eConstruct all possible Systematic (7,4) cyclic code using a generator polynomial
Section CAttempt any one part of the following: 07 x 1 = 07
- aDefine Power Spectral Density ( PSD) and state its relationship with the autocorrelation function
- bExplain the concept of a random process in the context of commu nication systems
- aExplain the Gram-Schmidt orthogonalization procedure used in si gnal space analysis
- bExplain the concept of line coding in digital communication systems. What are the important properties a good line code should have? For a binary data stream 1010101, draw the waveform representations using: I. Unipolar NRZ II. Polar NRZ
- aExplain the working principle of QPSK modulation with Mathemati cal representation of the QPSK signal, Constellation diagram and its significance
- bExplain the modulation and demodu lation process of Binary Ampli tude Shift Keying (BFSK) with the help of neat block diagrams. Also, sketc h the constellation diagram for BASK
- aDerive the impulse response and frequency response of a Matched Filter for a known signal s(t)
- bCompare the Bit Error Rate (BER) performance of Binary ASK (BASK), Binary FSK (BFSK), and Binary PSK (BPSK) in an AWGN channel. Also, justify why BPSK is preferred over BASK and BFSK in most practical systems
- aDefine and explain the concept of Mutual Information in the context of communication systems
- bFind the code word length by using Shannon Fano for the prob ability {0.4,0.2,0.2,0.1,0.1ሽ f o r s y m b o l s 𝑠ଵ,𝑠 ଶ,𝑠 ଷ,𝑠 ସ,𝑠 ହ Find the code efficiency, Redundancy and variance of the code of the code
Question text is extracted from the official AKTU question paper PDF above. Hindi translations are omitted — every question is printed in English in the original paper. Last verified: 2026-08-23.
Digital Communication — Other Year Papers
AKTU Digital Communication PYQs from other sessions
More B.Tech Semester 6 (2024-25) Papers
Other subjects from same semester and session
CMOS Digital Design Techniques2024-25Special Electrical Machines2024-25Augmented Virtual Reality2024-25Software Engineering2024-25River Engineering2024-25Data Compression2024-25Repair And Rehabilitation Of Structures2024-25Idea To Business Model2024-25
View all B.Tech Semester 6 2024-25 papers →Syllabus & More PYQs
Paper solve karne se pehle unit-wise syllabus dekh lo