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Frequency shift keying in digital communication and Frequency modulation in analog communication..........
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What is Attenuation distortion in networking?
Attenuation distortion is the distortion of an analog signal that occurs during transmission when the transmission medium does not have a flat frequency response across the bandwidth of the medium.
What is mean by power frequency withstand voltage and impulse withstand voltage?
Power frequency volatge is applied for a duration of one minute and as such there would be many cycles of sinusoidal wave form applied during the tets; hence, RMS value is considered. Whereas LI is a surge and is typically 1.20 micro sec. wave; hence peak is considered.
What technology have RFID tags replaced?
RFID tags, or Radio Frequency Identification tags, have been developed during the second world war, and they became more present in society throughout time. By now, RFID tags have even replaced barcode tags!
What is difference between pulse radar and CW radar?
CW or continuous-wave radar cannot determine range due to the lack of a listening period where the radar signal is silent. Pulse radar has a silent listening period (hence the name pulse radar). Therefore it can determine the range of the object causing the return by counting the elapsed time between transmission and receipt of the echo. The above is not quite correct, Continuous Wave Radar and Pulsed Radar differ by there relationship between the Pulse Width (tau) and the scene size (Swath). CW Radar's determine range by Frequency Modulation (FM) ranging this means that they ramp the RF frequency within the pulse during the transmission and are known as FMCW Radar. Pulsed Radar on the other hand use the pulse timing but can also use the FM Ranging trick to enhanced there signal to noise and reduce there probability of interference or detection/interception. CW radar can deduce range by delaying the transmit signal and mixing it with the receive such that it becomes a homodyne receiver and in such cases it is usual to ramp the RF and perhaps use two aerials rather then just one with a duplexer switch like in a Pulse radar system. Edit- hmm i feel the above answer is bit too complex... i don't think typical person would go as far as concerning FM or Pulse Delay Ranging here's my Answer DIFFERENCES BETWEEN PULSE AND CW RADAR Basis -Transmission Pulse RADAR puts delay between transmitting and receiving periods so the time between transmitted pulse and received pulse is different While CW RADAR, Transmit continuously -Antennas Pulse RADAR may use same antenna for Receiving and Transmitting , when transmitting the receiver is "blanked" and while Receiving the receiver is Activated and transmitter is blanked .. this is done by a device called "Duplexer" CW RADAR typically used 2 Antennas, one for transmit another one to Receive since there are no delay to receive as what usually seen in pulse RADAR -Ranging technique Pulse RADAR may use "Pulse Delay Ranging" to provide Range measurements , Frequency Modulation Ranging may also possible , especially for pulse RADAR that transmit many pulses and have very shot time to "listen" example is FMICW (Frequency Modulated Interrupted Continuous Wave RADAR) While CW RADAR provides Range by means of Doppler based Ranging (FM Ranging)
What is hp-hr mean?
horsepower hour outdated unite of energy "The unit represents an amount of work a horse is supposed capable of delivering during an hour (a horsepower integrated over a time interval of an hour)."
Which modulation can reduce the noice of signal?
Signals of different frequencies cannot interfere with each other. For example can audio waves (speech) interfere with AM or FM signals?? So when we perform modulation we just transfer the message to another amplitude/frequency/phase. Hence they will never interfere with signals which are not in the same range as them. Regards Arvind
In order to send more than one bit at a time during a single phase on a carrier modulation is used?
amplitude modulation is used
How are both frequency and wavelength related in terms of physics?
Frequency is how many waves pass a certain point during an amount of time. Wavelength is the distance between two points. Frequency and wavelength are inversely proportional in Physics. If the distance between the peaks of a wave decreases, the frequency of the wave increases. If the distance is increased, the frequency decreases.
What is the purpose of using Pulse Width Modulation?
A; PWM is extensively used in PWM power supply whereby a fix frequency is setup but the duty cycle change to transfer power. Actually the maximum power is transferred during the rise and fall of the square wave
The number of waves passing through a given point during the interval of one second?
That's called the frequency.
Can you explain how the transfer of energy as seismic waves is related to the frequency and magnitude of earthquake in a region?
They both based on the amount of energy that is released during earthquake
What do you called the amount of rain that falls in a place during a particular period?
no
What is called modem function?
A device which carries out the two important tasks of modulating and demodulating the analog signals is called a modem. The analog signals encode the digital information at the time of modulation and decodes it back during demodulation to transmit the data.
What is the amount of sound energy that flows through a given area in a specific amount of time?
Amplitude.Amplitude is directly related to the acoustic energy or intensity of a sound. Both amplitude and intensity are related to sound's power. All three of these characteristics have their own related standardized measurements
How is information transmitted using waves?
In the most extreme case, you can turn the wave on and off completely; this is commonly used in Ethernet for example. You can also modulate some aspect of the wave, such as amplitude (amplitude modulation), frequency (frequency modulation) or phase (phase modulation).Let's consider turning the wave signal on and off. The simplest way to transfer information this way is to agree to send (for example) one bit every second; in that case, if the signal is ON during one second, that might represent a "1", and if the signal is OFF during some other second, that might represent a "0". In practice, much more than one bit per second is usually transmitted (for example, 100 million bits every second is typical, nowadays, for home Ethernet); and more complicated systems are generally used to encode the signal.
What is an insulated device used for measuring the amount of heat absorbed or released during a reaction?
An insulated device used for measuring the amount of heat absorbed or released during a reaction is called a calorimeter.
What is meant by the frequency of a wave?
The number of waves that pass a point in 1 second
