D both a and b. Questions from Communication Systems. Principle on which an optical fibre work is. The purpose of modulating a signal in transmission is. A discontinuous signal signal value which appears in steps in predetermined levels is called.
Analog signal can be converted into digital signal and vice-versa with the help of a device called. Amplitude modulation has KCET Bandwidth requirement is greater and depends upon the modulating. Bandwidth requirement is twice the sum of the modulating signal frequency and the frequency deviation.
No of Sidebands. The number of sidebands are constant and equal to 2. The number of sidebands having significant amplitude depends upon the modulation index.
Zero crossings in modulating signal. Not equidistant. FM or PM transmitters are more complex than AM because the variation of modulating signal has to be converted and detected from the corresponding variation in frequencies. AM receivers are very less susceptible to noise because noise affects the amplitude, which is where information is stored in AM signals.
FM receivers are better immune to noise and it is possible to decrease noise by further deviation. Power is wasted in transmitting the carrier. Broadcasting FM, audio transmission in T. Frequency modulation is a technique of modulation, in which frequency of carrier varies in accordance with the amplitude of modulating signal. Keeping amplitude and phase constant.
The amplitude modulation is a technique of modulation in which the amplitude of the carrier wave varies in accordance with the amplitude of the modulating signal. Keeping frequency and phase constant. The phase modulation is a technique of modulation in which phase of the carrier wave varies in accordance with the amplitude of the modulating signal.
Keeping amplitude and frequency constant. AM receivers are very susceptible to noise. FM radio was developed in the United states in the s, mainly by Edwin Armstrong. Modulating differences In AM, a radio wave known as the "carrier" or "carrier wave" is modulated in amplitude by the signal that is to be transmitted.
The frequency and phase remain the same. In FM, a radio wave known as the "carrier" or "carrier wave" is modulated in frequency by the signal that is to be transmitted. The amplitude and phase remain the same. Pros and cons AM has poorer sound quality compared with FM, but is cheaper and can be transmitted over long distances. It has a lower bandwidth so it can have more stations available in any frequency range. FM is less prone to interference than AM.
However, FM signals are impacted by physical barriers. FM has better sound quality due to higher bandwidth. FM radio ranges in a higher spectrum from 88 to MHz.
OR to bits per second. Bandwidth Requirements Twice the highest modulating frequency. In AM radio broadcasting, the modulating signal has bandwidth of 15kHz, and hence the bandwidth of an amplitude-modulated signal is 30kHz. Twice the sum of the modulating signal frequency and the frequency deviation.
If the frequency deviation is 75kHz and the modulating signal frequency is 15kHz, the bandwidth required is kHz. Tranmitter and reciver are more complex as variation of modulating signal has to beconverted and detected from corresponding variation in frequencies.
Noise AM is more susceptible to noise because noise affects amplitude, which is where information is "stored" in an AM signal. In other words, there is a need to keep the amplitude of the carrier constant. This is precisely what we do in frequency modulation. Question Papers. Question Papers Textbook Solutions MCQ Online Tests 9.
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