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SubjectTopicYearType

The far field of an antenna varies with distance

\mathrm{r}

A loop is rotating about the

y

-axis in a magnetic field

\overrightarrow{\mathrm{E}}=\mathrm{B}_{0} \cos (\omega t+\phi) \vec{a}_{x} \mathrm{~T}

. The voltage in the loop is

The maximum usable frequency of an ionospheric layer at

60^{\circ}

incidence and with

8 \; \mathrm{mHz}

critical frequency is

An antenna in free space receives

2 \; \mu \mathrm{W}

of power when the incident electric field is

20 \mathrm{~m} \; \mathrm{V} / \mathrm{m} \; \mathrm{rms}

. The effective aperture of the antenna is

The radiation resistance of a circular loop of one turn is

0.01 \; \Omega

. The radiation resistance of five turns of such a loop will be

The vector

\mathrm{H}

in the far field of an antenna satisfies

The polarisation of wave with electric field vector

\overrightarrow{\mathrm{E}}=\mathrm{E}_{0} \; e^{j(\hat{\rho}(\omega t+\beta z)}\left(\vec{a}_{x}+\vec{a}_{y}\right)

The depth of penetration of wave in a lossy dielectric increases with increasing

The wavelength of a wave with propagation constant

(0.1 \pi+j 0.2 \pi) \mathrm{m}^{-1}

The time averages Poynting vector, in

W / m^{2}

, for a wave with

\vec{E}=24 \; e^{} \; a_{} \mathrm{~V} / \mathrm{m}

in free space is

All transmission line sections shown in the figure is have a characteristic impedance

\text{R}_{0}+\text{j}_{0}

. The input impedance

\text{Z}_{\text{in}}

equals

The Maxwell equation

\mathrm{V} \times \mathrm{H}=\mathrm{J}+\frac{\partial \overline{D}}{\partial t}

is based on

The intrinsic impedance of copper at high frequencies is

The probability density function of the envelope of narrow band Gaussian noise is

The spectral density of a real valued random process has

For a given data rate, the bandwidth

\mathrm{B}_{p}

of a

\text{BPSK}

signal and the bandwidth

\text{B}_{0}

of the

\mathrm{OOK}

signal are related as

Compression in

\text{PCM}

refers to relative compression of

The Fourier transform of a voltage signal

x(t)

X(f)

. The unit of

|X(f)|

Quadrature multiplexing is

\text{DSB-SC}

signal is generated using the carrier

\cos \left(\omega_{c}, t+\theta\right)

and modulating signal

x(t)

. The envelope of the

\text{DSB-SC}

signal is