Q1:

For a Hertz dipole antenna, the half power beam width (HPBW) in the E-plane is

Q2:

In a four element Yagi-Uda antenna

Q3:

If the diameter of a no dipole antennae is increased form $\frac{\lambda }{100}$ to $\frac{\lambda }{50}$, then its

Q4:

When a power P_t is transmitted by an antenna, amount of energy incident on the target is given by the expression.

Q5:

The characteristic impedance of TV receiving antenna cable is 300$\Omega$. If the conductors are made of copper separated by air are 1mm thick, what is the phase velocity and phase constant when receiving VHF channel 3 (63 MHz) and VHF 69(803 MHz)?

Q6:

A Hertzian dipole of length $\raisebox{1ex}{$\lambda $}\!\left/ \!\raisebox{-1ex}{$50$}\right.$is located at the origin. If a point P is located at a distance r from the origin then for what value of `r` the point will be in radiation zone.

Q7:

A certain antenna is used to radiate a 0.2GHz signal to a satellite in space. Given the radiation resistance of the antenna is 31.6$\Omega$. The antenna is

Q8:

When the two three-element arrays with current ratio 1 : 2 : 1 are displaced by $\raisebox{1ex}{$\lambda $}\!\left/ \!\raisebox{-1ex}{$2$}\right.$, then it forms:

Q9:

The polar radiation pattern of a $\raisebox{1ex}{$\lambda $}\!\left/ \!\raisebox{-1ex}{$8$}\right.$thin dipole antenna is

Q10:

A $\raisebox{1ex}{$\lambda $}\!\left/ \!\raisebox{-1ex}{$2$}\right.$dipole is kept horizontally at a height of$\raisebox{1ex}{${\lambda }_0$}\!\left/ \!\raisebox{-1ex}{$2$}\right.$above a perfectly conductivity infinite ground plane. The radiation pattern in the lane of dipole (E plane) looks approximately as

Q11:

Two identical antennas are placed in the $\theta =\raisebox{1ex}{$\pi $}\!\left/ \!\raisebox{-1ex}{$2$}\right.$plane as shown in Fig. The elements have

equal amplitude excitation with 180^o polarity difference, operating at wave length $\lambda .$The correct value of the magnitude of the far zone resultant electric field strength normalized with that of a single element both computed for $\varphi$ = 0, is

Q12:

Match List-I (type of Antenna) with List-II (Example) and select the correct answer using the codes given below the lists;

List-I	List-II
a. Aperture Antenna	1. Helical Antenna
b. Circularly polarized	2. Point Source Antenna
c. Frequency independent	3. Log Periodic Antenna
d. Isotropic Antenna	4. Micro strip antenna

 

Q13:

The frequency range for satellite communication is

Q14:

The radar in which both transmission and reception is done using the same antenna are called:

Q15:

The fibers mostly not used nowadays for optical fiber communication system are