Grade 10
  1. Mechanics  1.1. Dynamics  1.1.1. Motion in one dimension  1.1.2. Motion in two dimensions  1.1.3. Displacement and Distance  1.1.4. Speed and Velocity  1.1.5. Acceleration  1.1.6. Graphical representation of motion  1.1.7. Equations of motion  1.1.8. Free fall and acceleration due to gravity  1.1.9. Projectile motion  1.1.10. Relative speed  1.2. Dynamics  1.2.1. Newton's Laws of Motion  1.2.2. Inertia and mass  1.2.3. Force and its types  1.2.4. action and reaction force  1.2.5. Friction and its effects  1.2.6. Coefficient of friction  1.2.7. Circular motion  1.2.8. Centripetal force and centripetal acceleration  1.2.9. Momentum and Impulse  1.2.10. Conservation of momentum  1.2.11. Newton's third law and applications  1.3. Work, Energy and Power  1.3.1. Work done by the force  1.3.2. Work–energy theorem  1.3.3. Kinetic energy  1.3.4. Potential energy  1.3.5. Mechanical energy  1.3.6. Energy Conservation  1.3.7. Power and efficiency  1.3.8. Renewable and non-renewable energy sources  1.4. Gravitational force  1.4.1. Newton's law of universal gravitation  1.4.2. Gravitational field and field strength  1.4.3. Acceleration due to gravity on different planets  1.4.4. Kepler's laws of planetary motion  1.4.5. Orbits and satellites  1.4.6. Weight and apparent weight  1.4.7. Gravitational potential energy
  2. Properties of matter  2.1. States of matter  2.1.1. Solid, liquid and gas  2.1.2. Molecular structure of matter  2.1.3. Intermolecular forces  2.1.4. Plasma and Bose–Einstein condensate  2.2. Pressure  2.2.1. Definition of Pressure  2.2.2. Pressure in liquids  2.2.3. Atmospheric pressure  2.2.4. Pascal's principle  2.2.5. Archimedes' Principle and Buoyancy  2.2.6. Surface tension and capillarity  2.3. Elasticity  2.3.1. Hooke's law  2.3.2. Stress and strain  2.3.3. Elastic Limit and Modulus of Elasticity  2.3.4. Applications of Elasticity
  3. Thermal physics  3.1. heat and temperature  3.1.1. Difference Between Heat and Temperature  3.1.2. Temperature scale  3.1.3. Thermal expansion  3.1.4. Thermal equilibrium  3.2. Heat transfer  3.2.1. Conductivity  3.2.2. Convection  3.2.3. Radiation  3.2.4. Insulation and its applications  3.3. Thermal properties of matter  3.3.1. Specific heat capacity  3.3.2. Latent heat and phase change  3.3.3. Boiling and Melting Point  3.3.4. Heat engines and refrigeration  3.4. Laws of Thermodynamics  3.4.1. Zeroth law of thermodynamics  3.4.2. First law of thermodynamics  3.4.3. Second law of thermodynamics  3.4.4. Carnot cycle
  4. Waves and optics  4.1. Nature and properties of waves  4.1.1. Types of waves in nature and properties of waves  4.1.2. Transverse and longitudinal waves  4.1.3. Wave parameters  4.1.4. Reflection and refraction of waves  4.1.5. Superposition and Interference  4.1.6. Standing Waves and Resonance  4.1.7. Doppler effect  4.2. Sound waves  4.2.1. Characteristics of sound waves  4.2.2. Speed of sound in different mediums  4.2.3. Applications of sound waves  4.2.4. Ultrasound and its uses  4.3. Light Waves and Optics  4.3.1. Nature of light  4.3.2. Reflection of light  4.3.3. Laws of reflection  4.3.4. Mirrors and Image Formation  4.3.5. Refraction of light  4.3.6. Snell's Law  4.3.7. Lenses and Image Formation  4.3.8. Total internal reflection and critical angle  4.3.9. Optical fibre  4.4. Optical Instruments  4.4.1. Microscope  4.4.2. Telescope  4.4.3. Human eye and vision defects  4.4.4. Camera and its working principle
  5. Electricity and Magnetism  5.1. Electrostatics  5.1.1. Electric charge and its properties  5.1.2. Conductors and Insulators  5.1.3. Coulomb's law  5.1.4. Electric field and field lines  5.1.5. Electric potential and potential difference  5.1.6. Capacitors and Capacitance  5.2. Current Electricity  5.2.1. Electric current and its measurement  5.2.2. Ohm's law  5.2.3. Resistance and resistivity  5.2.4. Series and Parallel Circuits  5.2.5. Electric power and energy  5.2.6. Kirchhoff's Laws  5.3. Magnetism and Electromagnetism  5.3.1. Magnetic field and field lines  5.3.2. Magnetic effects of electric current  5.3.3. Electromagnetic induction  5.3.4. Faraday's laws of electromagnetic induction  5.3.5. Transformers and Applications  5.3.6. AC and DC current
  6. Modern Physics  6.1. Nuclear physics  6.1.1. Structure of the atom  6.1.2. Bohr's atomic model  6.1.3. Electron Energy Levels  6.1.4. X-rays and applications  6.2. Radioactivity  6.2.1. Types of radiation  6.2.2. Half-life and radioactive decay  6.2.3. Nuclear reactions and applications  6.2.4. Fission and Fusion  6.3. Quantum physics  6.3.1. Wave–particle duality  6.3.2. Photoelectric effect  6.3.3. Energy quantization  6.3.4. Heisenberg's uncertainty principle
  7. Electronics and Communication  7.1. Semiconductors  7.1.1. Conductors, Insulators and Semiconductors  7.1.2. Diodes and their applications  7.1.3. Transistors and Logic Gates  7.1.4. LEDs and photodiodes  7.2. Communication Systems  7.2.1. Basics of communication  7.2.2. Analog and digital signals  7.2.3. Wireless and optical fibre communication  7.2.4. Radio Waves and Modulation

Grade 10 → Electronics and Communication ↓


Communication Systems


Communication plays a vital role in our daily lives. Whenever we talk to someone, write a letter or send a message, we are involved in communication. Communication system in physics refers to various ways or methods of transmitting information from one place to another. With technology, communication systems have evolved and made our world smaller by connecting us in various ways, even from great distances.

Basic components of communication systems

Every communication system, whether ancient or modern, is made up of some basic components:

  1. Transmitter: It converts the message into a signal suitable for transmission. For example, in a radio station, the transmitter sends an audio message over radio waves.
  2. Medium/Channel: It is the physical path through which the signal travels from the transmitter to the receiver. It can be air, cable, fiber optics, etc.
  3. Receiver: It receives the transmitted signals and converts them back into a message format. For example, a radio receives radio waves and converts them into audio messages.

Types of communication systems

There are many types of communication systems, each with its own way of processing and transmitting information. Some of the most common types are:

1. Analog communication system

Analog communication systems transmit information using continuous signal changes. Signals may vary in amplitude, phase, or frequency. Telephone systems are classic examples of analog communication.

Analog Signal Example

In analog systems, keeping the signal intact is crucial for accurate communication. This is a challenging task because analog signals are prone to interference and noise.

2. Digital communication system

Digital communication uses discrete signals to convey information. It has gained importance due to its noise resistance, higher security and ability to hold more data compared to analog systems. Computers, smartphones and internet communication use digital methods.

Digital Signal Example

Digital signals represent data in binary form (0 and 1), making them less susceptible to interference.

The concept of modulation

Modulation is an important concept in communication systems, especially in radio and television broadcasting. Modulation involves changing the carrier signal according to the information requirement, which allows efficient transmission over long distances.

Types of modulation

There are a variety of modulation techniques, including:

  1. Amplitude modulation (AM): The amplitude of the carrier wave changes according to the information signal.
  2. Frequency modulation (FM): The frequency of the carrier wave changes according to the message signal.
  3. Phase modulation (PM): The phase of the carrier signal is modulated to code information.
Amplitude modulation example

In AM, the width or "amplitude" changes while other properties remain constant. FM, on the other hand, involves a change in frequency without affecting the amplitude.

Remittance and receipt

A communication system relies heavily on the efficiency of its transmitting and receiving processes. These processes ensure that data is transferred between the transmitter and receiver efficiently and accurately.

Transmitter components

The transmitter includes various components such as:

  • Oscillator: Generates a high frequency carrier wave.
  • Modulator: Combines the carrier wave with the information signal.
  • Amplifier: Strengthens the signal for transmission.
  • Antenna: Transmits the signal into the medium/channel.

Receiver components

The receiver section serves to receive and interpret the signal from the medium. The primary components are:

  • Antenna: Captures the transmitted signal.
  • Tuner: Selects the desired frequency.
  • Demodulator: Extracts the information signal from the carrier wave.
  • Amplifier: Strengthens the received signal for processing.

Communication system network

Multiple communication systems can be interconnected to form a network. Networks allow multiple devices to communicate with each other or with a central system. Examples include:

  • Telephone network: Connects landline telephones on a local, national, or international level.
  • Cellular network: The backbone of mobile communications, allowing mobile phones to connect to the Internet and to each other.
  • Internet: The largest network integrating smaller networks, enabling global communications.

The role of physics in communication systems

Physics provides the basis for understanding the principles behind communication systems:

Wave propagation

Communication depends on the propagation of electromagnetic waves, which carry signals over varying distances. The transmission speed and signal quality depend on understanding wave behaviour such as reflection, refraction and diffraction.

Signal and noise

Physics helps to analyze the degradation in signal due to noise which is any unwanted interference. A major challenge in communication is to maintain signal integrity by minimizing the effects of noise.

Practical example: mobile communication

Mobile phones are a quintessential example of modern communication systems. Here is a simple example of how mobile communication works:

  1. Someone speaks into the phone; the voice is converted into an electronic signal.
  2. This signal is transmitted to the nearby cell tower.
  3. The cell tower transmits the signal to the switching center, which sends the data to its destination.
  4. At the destination the signals travel back through the network to the receiver's phone.
  5. The phone converts the electronic signals back into sound waves so that the receiver can hear them.

Conclusion

Communication systems have revolutionized the way we communicate, share information, and work. From ancient smoke signals to modern satellites, the principles of physics have been at the core of continually enhancing communications. An understanding of these principles is vital, especially as we continue to invent and adapt new technologies for future communications challenges.


Grade 10 → 7.2


U
username
0%
completed in Grade 10

← Prev (7.1.4)
LEDs and photodiodes
Next (7.2.1) →
Basics of communication

Comments 



Communication Systems

https://www.physicsflow.com/g10/7.2?pfal=en