Study of Frequency Modulation of waves and its application

Frequency Modulation of unmodulated waves with the help of carrier waves and its application.

1. SCHEMA What are Signals? Modulation Frequency Modulation It’s types Mini FM Transmitter Demodulation Application of FM A way forward

2. The transmission of information by communication systems over large distances is quite a feat of human ingenuity. We can talk, video chat and text anyone on this planet! The  communication system  uses a very clever technique called Modulation to increase the reach of the signals. In this presentation, we will acknowledge about what Frequency Modulation is? What is Signal? A physical quantity that vary with time is known as signal. Ex . Alternating current

3. Analog Signal Analog Signal is a continuous sinusoidal waveform of a physical quantity. Unwanted (noise) signal also have small interference Ex . A.C. , temperature, etc. Digital signal Digital Signal is a discrete square pulse waveform having only two maxima and minima values i.e. 0 or 1 Noise gets nullified in digital signals Ex . Computer Data Signal, etc.

4. What is Modulation ? Modulation simply means ‘change’. It is the process of converting data into electrical signals optimized for transmission. Modulation is defined as the process of superimposing a low-frequency signal on a high-frequency carrier signal .

5. Types of Modulation

6. Frequency Modulation Frequency modulation (FM) is the encoding of  information  in a  carrier wave  by varying the  instantaneous frequency  of the wave. Frequency Modulation is of two types : Analog frequency modulation Digital frequency modulation The technology is used in  telecommunications ,  radio broadcasting ,  signal processing , and  computing .

7. Principle of Frequency Modulation Use of information bearing signal by carrier signal to modulate the frequency of message signal for transmission and proper end to end reception. WHAT ARE CARRIER SIGNALS? Carrier signals are high frequency signals that manipulate low frequency message signals. These are produced by electronic oscillator of a transmitter.

8. 1 km FM Transmitter mini circuit Materials Required- 2 100 ohm resistance, 104PF, 4.7 PF, 14 Gage, transistor, microphone, 3to 6 volt DC, radio frequency source Working- Here we have adapted the same formula by first amplifying the audio signal, generating a carrier signal using an oscillating and then modulating the carrier signal with the amplified audio signal. The amplification is done by an amplifier, whereas the modulation and carrier signal generation is done by an variable frequency oscillator circuit. The frequency is set at anywhere between the FM frequency range from 88MHz to 108MHz. The power of the FM signal from the oscillator is then amplified using a power amplifier to produce a low impedance output, matching that with the antenna.

9. Transmitter Receiver FM Broadcasting : Frequency modulation is widely used for  FM radio   broadcasting . It is also used in  telemetry ,  radar , seismic prospecting, and monitoring  newborns  for seizures via  EEG ,   two-way radio  systems,  sound synthesis , magnetic tape-recording systems and some video-transmission systems. In radio transmission, an advantage of frequency modulation is that it has a larger  signal-to-noise ratio  and therefore rejects  radio frequency interference  better than an equal power  amplitude modulation (AM)  signal. For this reason, most music is broadcast . Applicability of FM phenomenon

10. Doppler Radar: Doppler radar is a specialized  radar  that uses the  Doppler effect  to produce velocity data about objects at a distance It does this by bouncing a  microwave  signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal. This variation gives direct and highly accurate measurements of the  radial  component of a target's velocity relative to the radar. Magnetic Tape Recording: The development is described of an FM system for the recording of pressures and accelerations resulting from high explosive detonations. The intelligence from a pressure gage or accelerometer gage frequency modulates a carrier frequency after being multiplexed, this FM signal is transmitted by cable and remotely recorded on a magnetic tape recorder .

11. Stethoscope The bell is most effective at transmitting lower frequency sounds, while the diaphragm is most effective at transmitting higher frequency sounds. Bluetooth FM Transmitter A Bluetooth transmitter  enables devices to stream high-definition sound to speakers and headphones . They send out a signal for you to control from a phone or tablet. On the other hand, Bluetooth receivers attach to analog or digital stereo systems and allow you to listen from your phone to the speaker.

12. Demodulation Demodulation is defined as extracting the original information-carrying signal from a modulated carrier wave. A demodulator is an electronic circuit that is mainly used to recover the information content from the modulated carrier wave Frequency demodulation importance can be used at FM radio broadcasting, radar, seismic prospecting, telemetry, and monitoring infants for seizures using EEG.

13. Current Scenario of Great Indian Bustard Problem : High Tension Transmission Lines are creating chaos and threatening the lives of Great Indian Bustard especially in areas of Kutch, Jaisalmer(Rajasthan). Solution : Chirping sound (low frequency) produced by birds can be modulated. FM is used at  audio frequencies  to synthesize sound. This technique, known as  FM synthesis , was popularized by early digital  synthesizers. These electroacoustic devices should be cling on each antenna of transmission line . These modulators modify low frequency into high frequency sound signals ,and enable synthesizers to generate signals in the form of beep (or alert bell) that deviate their flight route away from poles and reduces the risk of their collision or electrocution .

14. A Way Forward to modulate the concept of Frequency Modulation The higher the frequency waves oscillate, the higher the pitch of the sound we hear . Electroacoustic device: An electroacoustic device used to generate SIGNALs with specific WAVEFORMs . Oscillators are used, for example, to test electronic circuits, to transmit radio signals, and to provide compositional material in the production of ELECTRONIC MUSIC and SOUND SYNTHESIS.

15. Let’s Summarize Frequency Modulation It’s basic principle 1 km FM mini transmitter circuit Analog and Digital Signal Modulation Applicability in various dimensions Demodulation A Way Forward

16. Thank You