RTU Kota B.Tech AI 5th Semester Wireless Communication Question Paper 2025

RTU Artificial Intelligence Wireless Communication 2025 Paper Review

Preparing for the Rajasthan Technical University B.Tech Wireless Communication exam requires a strict understanding of radio wave propagation, cellular architecture, and statistical channel modeling. For Artificial Intelligence students, wireless communication provides the structural pipeline for modern distributed applications. Edge computing, federated learning, and real-time internet-of-things (IoT) ecosystems rely entirely on high-throughput, low-latency wireless links. Optimizing AI model weights across distributed networks requires a firm grasp of channel capacity limits, signal degradation, and bandwidth efficiency. The 2025 paper tests your capability to calculate frequency reuse distance, solve path loss equations, and analyze multiple access mechanisms. Reviewing this specific branch paper shows you exactly how examiners frame the questions and allocate marks across the transmission modules. This systematic preparation helps you approach your fifth-semester exam confidently.

Understanding the AI Branch Exam Pattern

The RTU theory examination is a three-hour paper worth 70 marks. The paper features three distinct sections designed to evaluate both theoretical frameworks and quantitative communication problems.

• Part A: This section contains ten compulsory questions worth two marks each. You must define coherence bandwidth, state the handoff threshold criteria, differentiate between small-scale and large-scale fading, or compute a simple path loss value under 30 words.
• Part B: You will find seven questions here. You must answer five of them. Each question is worth four marks. Your answers require sketching the cellular frequency reuse pattern, explaining rake receiver operations, or calculating the received power using the free-space propagation model.
• Part C: This section offers five major questions. You need to answer three. Each question carries ten marks. These require you to solve complex co-channel interference ratio matrices, derive the bit error rate (BER) expressions for modulation schemes over fading channels, or compare structural capacities of CDMA, TDMA, and FDMA frameworks.

Core Topics Evaluated in the AI Paper

The 2025 question paper covers several critical modules that establish the mathematical rules for wireless data links. Focus your study time on these specific areas to maximize your score.

Cellular System Design Fundamentals

This module evaluates your understanding of spectral efficiency and network scaling. You must master the geometry of hexagonal cell structures. Practice calculating the total number of channels, cell capacity, and frequency reuse factor $Q$:

$$Q = \frac{D}{R} = \sqrt{3N}$$

where $D$ represents the distance between co-channel cell centers, $R$ is the cell radius, and $N$ is the cluster size. Study handoff strategies, interference reduction techniques, and cell splitting or sectoring methods used to increase traffic capacity.

Mobile Radio Propagation and Path Loss

Radio signals degrade significantly through space. You must understand large-scale path loss models, specifically the Free Space Friis transmission equation and the Log-distance Path Loss model. Practice calculating path loss exponents across varying indoor and outdoor terrains. The paper heavily features numerical problems where you must determine the minimum transmitter power required to maintain an acceptable Signal-to-Noise Ratio (SNR) at a specified kilometer distance.

Small-Scale Fading and Multipath

Multipath propagation causes rapid fluctuations in signal strength. You must categorize channels based on time dispersion (flat fading vs. frequency selective fading) and Doppler spread (fast fading vs. slow fading). Study the statistical parameters of the wireless channel, including delay spread, coherence bandwidth, Doppler shift, and coherence time. Memorize the physical conditions that dictate Rayleigh, Rician, and Nakagami fading distributions.

Digital Modulation and Diversity Techniques

To combat fading, wireless systems deploy advanced modulation and signal combining mechanisms. Review the performance of Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), and Minimum Shift Keying (MSK) under fading environments. Master the concept of spatial diversity. Study the operational logic behind selection combining, maximal ratio combining (MRC), and equal gain combining. Understand how equalization filters out inter-symbol interference (ISI).

Multiple Access and Wireless Standards

This module focuses on sharing the shared spectral medium among multiple active users. You must analyze the slot allocations in Time Division Multiple Access (TDMA), frequency divisions in Frequency Division Multiple Access (FDMA), and orthogonal spreading codes in Code Division Multiple Access (CDMA). Understand the evolution of wireless standards from GSM (2G) up to modern 5G New Radio architectures, focusing on orthogonal frequency division multiplexing (OFDM) and massive MIMO arrays.

Answer Writing Strategy for High Marks

RTU evaluators look for clean geometric cell diagrams, explicit variable declarations, and linear step-by-step mathematical calculations. Use a blue pen for descriptions and mathematical equations, and use a black pen and ruler for drawing hexagonal grids, signal fading waveforms, and block diagrams of receivers.

In Part A, answer directly. If a question asks for the definition of the Doppler shift, state clearly that it is the change in the received signal frequency caused by the relative motion between the transmitter and the mobile receiver, and write down its mathematical equation.

In Part B, use clear illustrations. When explaining cell sectoring, draw a clean seven-cell cluster and use directional arrows to show how 120-degree or 60-degree directional antennas restrict radiation paths and isolate co-channel interference.

In Part C, precision in calculation is critical. When solving a ten-mark frequency reuse problem, explicitly state every variable value before substitution. Write down the total allocated bandwidth, the control channel constraints, and the cluster size clearly. Show the division steps for obtaining channels per cell, and highlight your final capacity calculation by placing a neat block around it.

Time Management During the Exam

Allocate 20 minutes to Part A. Spend 40 minutes on Part B. Reserve the remaining 120 minutes for the three long-answer questions in Part C. Computing log-distance exponents, drawing multi-cluster frequency layouts, and calculating noise figures requires steady focus and significant time to prevent algebraic mistakes. This plan guarantees you 40 minutes per major question, giving you time to cross-verify your decibel-to-milliwatt (dBm) conversions. Use the final 10 minutes to verify your question numbering, ensure all matrix indexes match, and check that you have explicitly labeled all axes on signal propagation graphs.