Definitions [1]
A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal are ______.
A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. The frequencies of the resultant signal are 2005 kHz, 2000 kHz and 1995 kHz.
Explanation:
Amplitude modulated wave consists of three frequencies are ωc + ωm, ω, ωc - ωm
i.e. 2005 kHz, 2000 kHz and 1995 kHz.
Important Questions [60]
- Differentiate Between Amplitude Modulated (Am) and Frequency Modulated (Fm) Waves by Drawing Suitable Diagrams. Why is Fm Signal Preferred Over Am Signal?
- Write the Functions of the Transducer in Communication Systems
- What is the Function of a 'Repeater' Used in Communication System?
- Write the Functions of the Transmitter in Communication Systems:
- Write the Functions of the Modulator in Communication Systems
- Explain the Terms Attenuation Used in Communication System.
- Write the functions of the following in communication systems: Receiver
- Write the Functions of the Demodulator in Communication Systems
- Explain the term demodulation used in a communication system.
- Distinguish Between Broadcast Mode and Point-to-point Mode of Communication and Give One Example for Each.
- A Device X Used in Communication System Can Convert One Form of Energy into Another. Name the Device X. Explain the Function of a Repeater in a Communication System.
- Distinguish Between Point to Point and Broadcast Modes of Communication. Give an Example of Each.
- Write the Function of Receiver in Communication System.
- Write the functions of the transducer and repeaters.
- What is the Function of a Band Pass Filter Used in a Modulator for Obtaining Am Signal?
- Give Two Examples of Communication System Which Use Space Wave Mode. a Tv Tower is 80 M Tall. Calculate the Maximum Distance Upto Which the Signal Transmitted from the Tower Can Be Received.
- State Three Important Factors Showing the Need for Translating a Low Frequency Signal into a High Frequency Wave before Transmission
- The Carrier Wave is Represented by C ( T ) = 5 Sin ( 10 π T ) a Modulating Signal is a Square Wave as Shown. Determine Modulation Index.
- The Carrier Wave of a Signal is Given by C(T) = 3 Sin (8πT) Volt. the Modulating Signal is a Square Wave as Shown. Find Its Modulation Index.
- Define the Term Modulation. Draw a Block Diagram of a Simple Modulator for Obtaining Am Signal?
- Define Modulation Index.
- What is the Role of a Bandpass Filter?
- In the Block Diagram of a Simple Modulator for Obtaining an Am Signal, Shown in the Figure, Identify the Boxes a and B. Write Their Function.
- Given Modulation Index Physical Significance .For an Amplitude Modulated Wave, the Maximum Amplitude is Found to Be 10 V While the Minimum Amplitude is 2 V. Determine the Modulation Index μ ?
- In the Given Block Diagram of a Receiver, Identify the Boxes Labeled as X and Y and Write Their Functions.
- How Are Side Bands Produced?
- Draw a Sketch of a Sinusoidal Carrier Wave Along with a Modulating Signal
- A Carrier Wave of Peak Voltage 15 V is Used to Transmit a Message Signal. Find the Peak Voltage of the Modulating Signal in Order to Have a Modulation Index of 60%
- Find Modulation Index.
- Why is Modulation Index Kept Low?
- Answer the Following Question. Why a Signal Transmitted from a Tv Tower Cannot Be Received Beyond a Certain Distance? Write the Expression for the Optimum Separation Between the Receiving
- Explain Any Two Factors That Justify the Need of Modulating a Low-frequency Signal.
- How is Amplitude Modulation Achieved?
- The frequencies of two side bands in an AM wave are 640 kHz and 660 kHz respectively. Find the frequencies of carrier and modulating signal. What is the bandwidth required for amplitude modulation?
- Define the Term 'Amplitude Modulation'
- Explain any two factors which justify the need for modulating a low frequency base-band signal.
- Draw a Schematic Sketch Showing How Amplitude Modulated Signal is Obtained by Superposing a Modulating Signal Over a Sinusoidal Carrier Wave.
- Write Two Advantages of Frequency Modulation Over Amplitude Modulation.
- Answer the Following Question. If a and B Represent the Maximum and Minimum Amplitudes of an Amplitude-modulated Wave, Write the Expression for the Modulation Index in Terms of a and B.
- Solve the Following Question. a Message Signal of Frequency 20 Khz and Peak Voltage 10 V is Used to Modulate a Carrier of Frequency 2 Mhz and Peak Voltage of 15 V. Calculate the Modulation Index.
- Define amplitude modulation in a communication system.
- Write Three Important Factors Which Justify the Need of Modulating a Message Signal. Show Diagrammatically How an Amplitude Modulated Wave is Obtained When a Modulating Signal is Superimposed
- A Signal of 5 kHz Frequency is Amplitude Modulated on a Carrier Wave of Frequency 2 MHz. What Are the Frequencies of the Side Bands Produced?
- Draw a Block Diagram of a Detector for Am Signal
- What is Meant by Term ‘Modulation’? Draw a Block Diagram of a Simple Modulator for Obtaining an Am Signal.
- Why is Frequency Modulation Preferred Over Amplitude Modulation for Transmission of Music?
- Explain the Process of Amplitude Modulation.
- Show Graphically an Audio Signal, a Carrier Wave and an Amplitude Modulated Wave
- Give Three Reasons Why Modulation of a Message Signal is Necessary for Long Distance Transmission
- Why is Base Band Signal Not Transmitted Directly? Give Any Two Reasons
- By What Percentage Will the Transmission Ranges of Tv Tower Be Affected When the Height of the Tower is Increased by 21%?
- Why Are High Frequency Carrier Waves Used for Transmission?
- Block Diagram of a Receiver is Shown in the Figure:(A) Identify ‘X’ and ‘Y’. (B) Write Their Functions.
- Differentiate Between Analog and Digital Communication.
- What Do You Mean by Bandwidth of a Signal? Give Its Importance.
- Draw a Diagram Showing an Amplitude Modulated Wave by Superposing a Modulating Signal Over a Sinusoidal Carrier Wave.
- Write Any Two Factors Which Justify the Need for Modulating a Signal ?
- Write briefly any two factors which demonstrate the need for modulating a signal. Draw a suitable diagram to show amplitude modulation using a sinusoidal signal as the modulating signal.
- Distinguish Between ‘Analog and Digital Signals’.
- Answer the Following Question : Define 'Bandwidth' and Describe Briefly Its Importance in Communicating Signals ?
Concepts [11]
- Detection of Amplitude Modulated Wave
- Production of Amplitude Modulated Wave
- Basic Terminology Used in Electronic Communication Systems
- Sinusoidal Waves
- Modulation and Its Necessity
- Amplitude Modulation (AM)
- Need for Modulation and Demodulation
- Satellite Communication
- Propagation of EM Waves
- Bandwidth of Transmission Medium
- Bandwidth of Signals
