# Electrical engineering/Microwave Engineering MCQs Set-8 Sample Test,Sample questions

## Question: ``` If a ferrite slab produces a phase shift of 0.836 rad/ cm, then the length of the slab required to produce a phase shift of 135â° is: ```

1.2.81 cm

2.3 cm

3.2 cm

4.3.4 cm

Posted Date:-2022-06-02 07:27:16

## Question: ``` Power radiated from an antenna per unit solid angle is called radiation intensity. ```

1.True

2.False

Posted Date:-2022-05-31 18:11:01

## Question: ```A Dicke radiometer is identical to the total power radiometer in all aspects except that they have different receiving antenna. ```

1.True

2. False

Posted Date:-2022-05-31 18:05:34

## Question: ```A gyrator can be made a passive device by certain design methods so that they do not affect the power levels of the circuit in which they are used. ```

1.True

2.False

Posted Date:-2022-06-02 07:27:45

## Question: ```A major challenge in designing a radiometer is: ```

1.Design complexity

2.High cost

4.None of the mentioned

Posted Date:-2022-05-31 18:02:50

## Question: ```A parabolic reflector used for reception with the direct broadcast system is 18 inches in diameter and operates at 12.4 GHz. The far-field distance for this antenna is: ```

1.18 m

2. 13 m

3.16.4 m

4.17.3 m

Posted Date:-2022-05-31 17:37:48

## Question: ```A radio receiver operating at microwave frequencies must have very high selectivity. ```

1.True

2.False

Posted Date:-2022-05-31 17:44:21

## Question: ```A receiver system is operating at a bandwidth of 1 MHz and has a total system noise temperature of 762 K. then the output noise power is: ```

1.-110 dBm

2.-234 dBm

3. -145 dBm

4.-124 dBm

Posted Date:-2022-05-31 17:54:08

## Question: ```A source has a cosine power pattern that is bidirectional. Given that the directivity of a unidirectional source with cosine power pattern has a directivity of 4, then the directivity of the unidirectional source is: ```

1.1

2.2

3.4

4.8

Posted Date:-2022-05-31 18:23:28

## Question: ```A source has a sine squared radiation intensity power pattern. The directivity of the given source is: ```

1.1.5

2.3

3.2.5

4.3.5

Posted Date:-2022-05-31 18:24:14

## Question: ```A typical radiometer would measure the brightness temperature over the range of about: ```

1.50-300 K

2.100-200 K

3.400-500 K

4.None of the mentioned

Posted Date:-2022-05-31 18:06:14

## Question: ```A ________ determines the target range by measuring the round trip time of a pulsed microwave signal. ```

4.None of the mentioned

Posted Date:-2022-05-31 17:58:43

## Question: ```A __________ is a device that converts a guided electromagnetic wave on a transmission line into a plane wave propagating in free space. ```

1.Transmitting antenna

2.Receiving antenna

4.Mixer

Posted Date:-2022-05-31 17:35:51

## Question: ```According to Planckâ€™s radiation law, a body can radiate energy to the medium surrounding it under all conditions invariably. ```

1.True

2.False

Posted Date:-2022-05-31 18:02:16

## Question: ```Advantage of HJT over BJT is that it has: ```

1.higher gain

2.high frequency of operation

3.sophisticated construction

4.none of the mentioned

Posted Date:-2022-06-02 07:23:31

## Question: ```All modern wireless communication systems rely on digital modulation methods due to: ```

1.superior performance

2.low power requirements

3.sustainability

4. all of the mentioned

Posted Date:-2022-05-31 17:45:05

## Question: ```An antenna source that radiates energy uniformly in all the directions is called: ```

1.Isotropic source

2.Anisotropic source

3.Point source

4. None of the mentioned

Posted Date:-2022-05-31 18:22:35

## Question: ```Antenna noise temperature of a system is 210 K, noise temperature of transmission line is 123 K, loss of a transmission line connecting the antenna to receiver is 1.41 and noise temperature of the receiver cascade is 304 K. then the total system noise temperature is: ```

1.840 K

2.762 K

3.678 K

4. 1236 K

Posted Date:-2022-05-31 17:53:00

## Question: ```Antenna that does not belong to the horn antenna family among the following are: ```

1.Pyramidal horn

2.Conical horn

3.bi-conical horn

4.None of the mentioned

Posted Date:-2022-05-31 18:17:25

## Question: ```Antennas are bidirectional devices. ```

1.True

2.False

Posted Date:-2022-05-31 17:36:09

## Question: ```Antennas having a constant pattern in the azimuthal plane are called _____________ ```

1.High gain antenna

2.Omni directional antenna

3.Unidirectional antenna

4.Low gain antenna

Posted Date:-2022-05-31 17:38:59

## Question: ```Antennas that radiate energy only in a specified are called anisotropic antennas. ```

1.True

2. False

Posted Date:-2022-05-31 18:22:53

## Question: ```As the beam area of an antenna decreases, the directivity of the antenna: ```

1.Increases

2.Decreases

3.Remains unchanged

4.Depends on the type of the antenna

Posted Date:-2022-05-31 18:11:51

## Question: ```Based on the size of the loops, loop antennas are classified as small and large loops. This is the only classification of loop antenna. ```

1.True

2.False

Posted Date:-2022-05-31 18:16:40

## Question: ```Beamwidth and directivity are both measures of the focusing ability of an antenna. ```

1.True

2.False

Posted Date:-2022-05-31 17:39:27

## Question: ```Bluetooth devices operate at a frequency of : ```

1.2.4 GHz

2.4.5 GHz

3.5.7 GHz

4.none of the mentioned

Posted Date:-2022-05-31 17:49:33

## Question: ```Construction of pulse radar is much simpler than a Doppler radar. ```

1.True

2.False

Posted Date:-2022-05-31 17:59:03

## Question: ```Dipole antennas are an example for: ```

1.Wire antennas

2. Aperture antennas

3.Array antennas

4.None of the mentioned

Posted Date:-2022-05-31 17:36:41

## Question: ```Effective aperture is a parameter of the antenna that gives the physical aperture of the antenna. ```

1.True

2.False

Posted Date:-2022-05-31 18:14:38

## Question: ```Ferrite phase shifters have more advantages over FETs and diodes in using them in microwave integrated circuits. ```

1.True

2. False

Posted Date:-2022-06-02 07:28:08

## Question: ```For applications like missile fire control, bistatic radars are used. ```

1.True

2.False

Posted Date:-2022-05-31 17:57:22

## Question: ```For radar system, antennas with a large beam width are preferred over narrow beam antennas. ```

1.True

2.False

Posted Date:-2022-05-31 17:56:32

## Question: ```Given that the antenna efficiency is 0.9, equivalent brightness temperature is 200 K; physical temperature is 300 K, noise temperature of an antenna is: ```

1.220 K

2.210 K

3. 240 K

4.None of the mentioned

Posted Date:-2022-05-31 17:51:49

## Question: ```Global positioning system uses _____ satellites in medium earth orbits to provide accurate position information. ```

1.12

2.24

3. 36

4.48

Posted Date:-2022-05-31 17:46:53

## Question: ```GPS operates at a single frequency band. ```

1.true

2.false

Posted Date:-2022-05-31 17:47:32

## Question: ```Hetero junction bipolar transistors have the same working principle and operation as that of a BJT. ```

1.true

2.false

Posted Date:-2022-06-02 07:22:57

## Question: ```High directivity required in RADAR communication is satisfied using this type of antennas: ```

1.Wide band antennas

2.Antenna arrays

3.Slot antennas

4.Patch antennas

Posted Date:-2022-05-31 18:21:09

## Question: ```Ideally, the number of point sources an antenna can resolve is numerically equal to: ```

1.Gain of the antenna

2.Directivity

3.Beam efficiency

4.Beam area

Posted Date:-2022-05-31 18:14:14

## Question: ```If a receiver is operating at a bandwidth of 1 MHz and has antenna noise temperature of 210 K, then the input noise power is: ```

1.-90 dBm

2.-115 dBm

3.-56 dBm

4.-120 dBm

Posted Date:-2022-05-31 17:52:26

## Question: ```If a transistor has a short circuit current gain of 25 and the capacitance measured in the hybrid-Ï€ model of the transistor was 60 pF. Then the threshold frequency of operation of the transistor is: ```

1.60 MHz

2.45.6 GHz

3.66.3 GHz

4. 34.8 GHz

Posted Date:-2022-06-02 07:14:06

## Question: ```If an antenna radiates over half a sphere, directivity of the antenna is: ```

1.Two

2.Four

3.Three

4. One

Posted Date:-2022-05-31 18:12:21

## Question: ```If the beam width of an antenna in two orthogonal planes are 300 and 600. Then the directivity of the antenna is: ```

1.24

2.18

3.36

4.12

Posted Date:-2022-05-31 17:39:59

## Question: ```If the distance between a transmitting station and receiving station is 1 Km and if the antennas are operating at a wavelength of 5 cm, then the path loss is: ```

1.108 dB

2.12 dB

3. 45 dB

4.48 dB

Posted Date:-2022-05-31 17:42:43

## Question: ```If the power input to an antenna is 100 mW and if the radiated power is measured to be 90 mW, then the efficiency of the antenna is: ```

1.75 %

2.80 %

3. 90 %

4.Insufficient data

Posted Date:-2022-05-31 17:40:34

## Question: ```If the received power at antenna terminals is -80dBm, and if the input noise power is -115 dBm, then the input SNR is: ```

1.45 dB

2.-195 dB

3.-35 dB

4.35 dB

Posted Date:-2022-05-31 17:53:34

## Question: ```If the received power at the antenna terminals is Si=-80 dBm and the output noise power is -110 dBm then the output signal to noise ratio is given by: ```

1.30 dB

2.-30 dB

3.35 dB

4.-35 dB

Posted Date:-2022-05-31 17:55:00

## Question: ```In a RADAR system the transmitter of the radar is more sensitive than the receiver. ```

1.True

2.False

Posted Date:-2022-05-31 17:56:11

## Question: ```In a receiver, if the noise figure of the mixer stage in the receiver is 7 dB, then the equivalent noise temperature is given that the receiver is operating at 290 K: ```

1.1163 K

2. 1789 K

3.1000 K

4.1234 K

Posted Date:-2022-05-31 17:51:13

## Question: ```In military applications the radar cross sections of vehicles is minimized. ```

1.True

2.False

Posted Date:-2022-05-31 17:59:25

## Question: ```In this method of wireless communication, communication happens only in one direction: ```

1.Simplex

2.Duplex

3.Half duplex

4.None of the mentioned

Posted Date:-2022-05-31 17:42:03

## Question: ```Lens antennas are classified into two types. One being fast antenna, the other one is: ```

1.Slow antenna

2.Delay antenna

3.Dynamic antenna

4.None of the mentioned

Posted Date:-2022-05-31 18:20:00

## Question: ```Link margin that is used to account for fading effects is called fade margin. ```

1.True

2.False

Posted Date:-2022-05-31 17:43:39

## Question: ```Low is the G/T ratio of an antenna, higher is its efficiency. ```

1.True

2.False

Posted Date:-2022-05-31 17:33:29

## Question: ```Most of the wireless systems today operate at a frequency of about: ```

1.800 MHz

2.100 MHz

3.80 MHz

4.None of the mentioned

Posted Date:-2022-05-31 17:41:13

## Question: ```One of the most important requirements of a radio receiver is high gain. ```

1.True

2.False

Posted Date:-2022-05-31 17:43:59

## Question: ```Patch antennas are the antennas of small size and are made of: ```

1.Strip line

2.Microstrip lines

3.Coaxial cables

4.Rectangular waveguide

Posted Date:-2022-05-31 18:17:55

## Question: ```Point to point communication systems use low gain antennas for communication. ```

1.True

2.False

Posted Date:-2022-05-31 17:41:33

## Question: ```Probability of bit error is greater for ASK as compared to FSK. ```

1.true

2.false

Posted Date:-2022-05-31 17:45:45

## Question: ```Probability of bit error rate is greater for QPSK as compared to FSK. ```

1.true

2.false

Posted Date:-2022-05-31 17:46:11

## Question: ```Pulse radar operating at 10GHz frequency has an antenna with a gain of 28 dB and a transmitted power of 2kW. If it is desired to detect a target of cross section 12m2, and the minimum detectable signal is -90 dBm, the maximum range of the radar is: ```

1.8114 m

2.2348 m

3.1256 m

4.4563 m

Posted Date:-2022-05-31 17:59:59

## Question: ```Radiometry is a technique or the principle on which radar works. ```

1.True

2.False

Posted Date:-2022-05-31 18:01:55

## Question: ```Reciprocal phase shifters give different phase shift in different direction. ```

1.True

2.False

Posted Date:-2022-06-02 07:26:19

## Question: ```Reflector antennas are widely used to modify radiation patterns of radiating elements. ```

1.True

2.False

Posted Date:-2022-05-31 18:18:15

## Question: ```The amount of power by which the received power must be greater than the threshold level required to maintain a minimum quality of service is called _______ ```

1.Line loss

4.None of the mentioned

Posted Date:-2022-05-31 17:43:17

## Question: ```The antenna in which location of the feed determines the direction of the lobe are: ```

1.Wire antenna

2.Loop antenna

3.Helical antenna

4. Horn antenna

Posted Date:-2022-05-31 18:16:23

## Question: ```The antennas which offer high operational bandwidth and the antenna parameters are maintained over a wide range of antennas are called: ```

1.Wide band antennas

2.Array antennas

3.Parabolic antennas

4.None of the mentioned

Posted Date:-2022-05-31 18:20:32

## Question: ```The basic equation of radiation that is applied to any antenna irrespective of the type of the antenna is: ```

1.iL= Qv

2.iQ = Lv

3.i/L=Q/v

4.None of the mentioned

Posted Date:-2022-05-31 18:08:20

## Question: ```The basic requirements of transmitting antennas are: ```

1.High efficiency

2.Low side lobes

3.Large signal to noise ratio

4.Lone of the mentioned

Posted Date:-2022-05-31 18:07:18

## Question: ```The beam width of the antenna pattern measured at half power points is called: ```

1.Half power beam width

2.Full null beam width

3.Beam width

4. None of the mentioned

Posted Date:-2022-05-31 18:10:01

## Question: ```The current gain of a BJT ________ with frequency. ```

1.increases

2.decreases

3.remains constant

4.none of the mentioned

Posted Date:-2022-06-02 07:13:28

## Question: ```The dominant factor affecting the accuracy of the total power radiometer is the variation of ___________ ```

1.Gain in the overall system

2.The feedback circuit

3.Efficiency of the system

4.None of the mentioned

Posted Date:-2022-05-31 18:05:12

## Question: ```The half power beam width of an antenna in both Î¸ and Ï† are 400 each. Then the gain of the antenna is: ```

1.23

2.25

3.14

4.27

Posted Date:-2022-05-31 18:12:57

## Question: ```The hybrid-Ï€ model of a BJT is useful for analysis at all frequency ranges and variation of other transistor parameters. ```

1.true

2.false

Posted Date:-2022-06-02 07:12:15

## Question: ```The integrator circuit after the detector in the receiver circuit is used to smooth out the short term variations in the signal power. ```

1.True

2.False

Posted Date:-2022-05-31 18:04:17

## Question: ```The members of the antenna family which are made of wires of certain value in terms of operating wavelength are called: ```

1.Loop antennas

2.Wire antennas

3.Dipole antenna

4.Slot antennas

Posted Date:-2022-05-31 18:15:50

## Question: ```The modulation technique in which both amplitude and phase of the carrier are varied simultaneously is: ```

2.BPSK

3.QAM

4.QPSK

Posted Date:-2022-05-31 17:50:03

## Question: ```The noise power will determine the maximum detectable signal level for a receiver. ```

1.True

2.False

Posted Date:-2022-05-31 17:50:36

## Question: ```The noise temperature of an antenna is given by the expression: ```

4.None of the mentioned

Posted Date:-2022-05-31 17:34:01

## Question: ```The number N of radio transmitters or point sources of radiation distributed uniformly over the sky which an antenna can resolve is given by: ```

4.None of the mentioned

Posted Date:-2022-05-31 18:13:28

## Question: ```The number of patterns radiation pattern required to specify the characteristic are : ```

1.Three

2.Four

3.Two

4.Five

Posted Date:-2022-05-31 18:09:24

## Question: ```The output collector to emitter current of a BJT amplifier is independent of the input base current of the amplifier. ```

1.true

2.false

Posted Date:-2022-06-02 07:12:52

## Question: ```The pattern of the reflector in a reflector antenna is called: ```

1.Primary pattern

2.Secondary pattern

3.Reflector pattern

4.None of the mentioned

Posted Date:-2022-05-31 18:18:46

## Question: ```The probability of error depends on the ratio of bit energy to noise power density. ```

1.true

2.false

Posted Date:-2022-05-31 17:45:26

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

Posted Date:-2022-05-31 17:57:03

## Question: ```The receiver model of a total power radiometer is based on the: ```

4.None of the mentioned

Posted Date:-2022-05-31 18:03:22

## Question: ```The solid area through which all the power radiated by the antenna is: ```

1.Beam area

2.Effective area

3.Aperture area

4.Beam efficiency

Posted Date:-2022-05-31 18:10:42

## Question: ```The system bandwidth of a total power radiometer is determined by the: ```

1.RF amplifier

2. Local oscillator

3. IF filter

4.IF amplifier

Posted Date:-2022-05-31 18:03:54

## Question: ```The term radar cross section defines the: ```

1.Scattering ability of the target

3.Amount of energy scattered by unwanted objects

4.Cross section of radar area through which energy is emitted

Posted Date:-2022-05-31 17:57:57

## Question: ```The terminal impedance of a dipole antenna is 710 Î©. The terminal impedance of the slot antenna given the intrinsic impedance of air is 377 Î© is: ```

4.None of the mentioned

Posted Date:-2022-05-31 18:21:42

## Question: ```There is no standard to be formed by commercial WLAN products. ```

1.true

2.false

Posted Date:-2022-05-31 17:48:17

## Question: ```When the separation between two lines that carry the TEM wave approaches Î» the wave tends to be radiated. ```

1.True

2.False

Posted Date:-2022-05-31 18:08:43

## Question: ```WLAN is used for providing connection between a host computer and satellite for communication. ```

1.true

2.false

Posted Date:-2022-05-31 17:47:51

## Question: ```_____ is a device that produces a phase shift of a required amount of the input wave. ```

1.Phase shifter

2.Attenuator

3.Resonator

4. None of the mentioned

Posted Date:-2022-06-02 07:25:44

## Question: ```______ antennas have gain less than reflector antennas but have more lenient tolerance on surfaces. ```

1.Helical antennas

2.Lens antennas

3.Array antennas

4.Slot antennas

Posted Date:-2022-05-31 18:19:31

## Question: ```_______ of an antenna is defined as the ratio of the induced voltage to the incident electric field. ```

1.Effective height

2.Gain

3. Directivity

4.Loss

Posted Date:-2022-05-31 18:15:06

## Question: ```________ of an antenna is a plot of the magnitude of the far field strength versus position around the antenna. ```

2.Directivity

3.Beam width

4.None of the mentioned

Posted Date:-2022-05-31 17:38:25

## Question: ```_________ antennas consist of a regular arrangement of antenna elements with a feed network ```

1.Aperture antennas

2.Array antennas

3.Printed antennas

4.Wire antennas

Posted Date:-2022-05-31 17:37:14

## Question: ```_________ has a constant power spectral density. ```

1.White noise

2.Gaussian noise

3.Thermal noise

4.Shot noise

Posted Date:-2022-05-31 17:34:46

## Question: ```_________ is a device that converts electrons to photons or vice-versa. ```

1.Antenna

2.Electron gun

3.Photon amplifier

4.Microwave tube

Posted Date:-2022-05-31 18:07:49

2.Sonar