A signal is to be transmitted through a wave | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) For efficient transmission and reception of signals,the length $l$ of a linear antenna should be comparable to the wavelength $\lambda$ of the sig

Vedclass · Accepted Answer

$\lambda, P_{eff} = K\left(\frac{1}{\lambda}\right)^2$

Vedclass · Answer

(A) For efficient transmission and reception of signals,the length $l$ of a linear antenna should be comparable to the wavelength $\lambda$ of the signal. Typically,$l = \frac{\lambda}{4}$ or $l = \frac{\lambda}{2}$ are standard lengths. Among the given options,the length must be a fraction of $\lambda$.The power radiated $P_{eff}$ by a linear antenna is proportional to the square of the ratio of the antenna length to the wavelength. Specifically,$P_{eff} \propto \left(\frac{l}{\lambda}\right)^2$. Since $l$ is proportional to $\lambda$,we have $P_{eff} \propto \left(\frac{\lambda}{\lambda}\right)^2$ is not the case here; rather,for a fixed antenna length,the power radiated is inversely proportional to the square of the wavelength,i.e.,$P_{eff} \propto \frac{1}{\lambda^2}$.Thus,$P_{eff} = K \left(\frac{1}{\lambda}\right)^2$. Comparing this with the options,option $A$ provides the correct relationship for power,and the length $\lambda$ is a standard order of magnitude for antenna design.

$A$ signal is to be transmitted through a wave of wavelength $\lambda$,using a linear antenna. The length $l$ of the antenna and effective power radiated $P_{eff}$ will be given respectively as: ($K$ is a constant of proportionality)

Similar Questions

The total maximum transmitted power in amplitude modulation if the carrier output power is $1 \ kW$ is

$A$ signal of $5\ kHz$ frequency is amplitude modulated on a carrier wave of frequency $2\ MHz$. The frequencies of the resultant signal is/are

The electron density of $E, F_1, F_2$ layers of the ionosphere is $2 \times 10^{11} \, m^{-3}$,$5 \times 10^{11} \, m^{-3}$,and $8 \times 10^{11} \, m^{-3}$ respectively. What is the ratio of critical frequencies for the reflection of radio waves?

Choose the correct statement for amplitude modulation.

$A$ carrier wave of peak voltage $60 \,V$ is used to transmit a message signal. Then the peak voltage of the modulating signal in order to have a modulation index of $90 \%$ is (in $\,V$)

Vedclass Test Series

Exam Paper Generator

Online Exam Module