GATE ECE 1998 | Antennas Question 30 | Electromagnetics

GATE ECE 1998

MCQ (Single Correct Answer)

-0.3

An antenna in free space receives 2$$\mu $$ W of power when the incident electric field is 20 m V/m rms. The effective aperture of the antenna is

0.005 $${m^2}$$

0.05 $${m^2}$$

1.885 $${m^2}$$

3.77 $${m^2}$$

GATE ECE 1998

MCQ (Single Correct Answer)

-0.3

The far field of an antenna varies with distance r as

1/r

1 / $${r^2}$$

1 / $${r^3}$$

$${1 \over {\sqrt r }}$$

GATE ECE 1998

MCQ (Single Correct Answer)

-0.3

The vector $$\mathop H\limits^ \to $$ in the far field of an antenna satisfiels

$$\nabla .\,\mathop H\limits^ \to = 0\,\,and\,\,\nabla \times \,\mathop H\limits^ \to = 0\,$$

$$\nabla .\,\mathop H\limits^ \to \ne 0\,\,and\,\,\nabla \times \,\mathop H\limits^ \to \ne 0$$

$$\nabla .\,\mathop H\limits^ \to = 0\,\,and\,\,\nabla \times \,\mathop H\limits^ \to \ne 0\,\,$$

$$\nabla .\,\mathop H\limits^ \to \ne 0\,\,and\,\,\nabla \times \,\mathop H\limits^ \to = 0\,\,$$

GATE ECE 1995

MCQ (Single Correct Answer)

-0.3

An antenna when radiating, has a highly directional radiation pattern. When the antenna is receiving its radiation pattern

is more directive

is less directive

is the same

exhibits no directivity at all

PREVIOUS NEXT

GATE ECE Subjects

Network Theory

State Equations For Networks Network Elements Network Theorems Two Port Networks Transient Response Sinusoidal Steady State Response Network Graphs Miscellaneous

Control Systems

Basic of Control Systems Signal Flow Graph and Block Diagram Time Response Analysis Stability Root Locus Diagram Frequency Response Analysis Compensators State Space Analysis

Electronic Devices and VLSI

Semiconductor Physics PN Junction BJT and FET IC Basics and MOSFET

Analog Circuits

Bipolar Junction Transistor FET and MOSFET Oscillators Operational Amplifier 555 Timer Frequency Response Diodes Feedback Amplifier Power Amplifier

Digital Circuits

Number System and Code Convertions Boolean Algebra Logic Gates Combinational Circuits Sequential Circuits Semiconductor Memories Logic Families Analog to Digital and Digital to Analog Converters

Microprocessors

Pin Details of 8085 and Interfacing with 8085 Instruction Set and Programming with 8085

Signals and Systems

Representation of Continuous Time Signal Fourier Series Discrete Time Signal Fourier Series Fourier Transform Discrete Time Signal Z Transform Continuous Time Linear Invariant System Transmission of Signal Through Continuous Time LTI Systems Discrete Time Linear Time Invariant Systems Sampling Continuous Time Signal Laplace Transform Discrete Fourier Transform and Fast Fourier Transform Transmission of Signal Through Discrete Time Lti Systems Miscellaneous Fourier Transform

Communications

Fundamentals of Information Theory Noise In Digital Communication Analog Communication Systems Digital Communication Systems Random Signals and Noise

Electromagnetics

Maxwell Equations Transmission Lines Uniform Plane Waves Waveguides Antennas Miscellaneous

General Aptitude

Numerical Ability Logical Reasoning Verbal Ability

Engineering Mathematics

Linear Algebra Calculus Vector Calculus Complex Variable Probability and Statistics Differential Equations Numerical Methods Transform Theory