PHYSICS S5 Unit 11: Mobile Phone and Radio Communication

What Will You Learn?

• The course Unit 11: Mobile Phone and Radio Communication provides a comprehensive overview of the fundamental principles of wireless communication, focusing specifically on how radio waves are used to transmit information and how modern cellular networks operate.
• I. Radio Communication Fundamentals
• This section covers the basic physics and engineering principles behind all wireless transmission.
• • Electromagnetic Waves: You will study radio waves as a specific part of the electromagnetic spectrum, understanding the relationship between wavelength (λ), frequency (f), and the speed of light (c).
• • Transmitters and Receivers: You'll learn the basic block diagrams and functions of a transmitter (which encodes information onto a carrier wave) and a receiver (which extracts the information from the carrier wave).
• • Modulation: The core process of encoding information onto a high-frequency carrier wave. You will study basic analog techniques:
• o Amplitude Modulation (AM): Varying the amplitude of the carrier wave proportional to the signal.
• o Frequency Modulation (FM): Varying the frequency of the carrier wave proportional to the signal.
• • Propagation: How radio waves travel, including concepts like ground waves, sky waves (reflection off the ionosphere), and line-of-sight communication.
• II. Mobile Phone Technology (Cellular Networks)
• This section focuses on the architecture and evolution of modern mobile communication.
• • Cellular Concept: You will learn the revolutionary idea of dividing a service area into many small geographic areas called cells. Each cell has a low-power transmitter (base station).
• o Frequency Reuse: This core concept allows the same set of radio frequencies to be reused in non-adjacent cells, which is essential for maximizing system capacity and supporting millions of users.
• • Mobile Switching Center (MSC): The central hub that coordinates call routing, tracking, and the crucial process of handoff between base stations.
• • Handoff: The automatic process by which a mobile phone switches its connection from one base station to another as the user moves between cells, ensuring continuous service without dropping the call.
• • Generations of Mobile Communication (1G to 5G): You will study the evolution of cellular standards:
• o 2G (e.g., GSM): Introduced digital voice transmission.
• o 3G/4G (LTE): Enabled high-speed data services, facilitating mobile internet access and streaming.
• o 5G: Focuses on ultra-fast speeds, massive connectivity (IoT), and ultra-low latency.
• • Digital Transmission: The reliance on digital signals for voice and data transmission in modern mobile networks, which offers superior noise immunity and data efficiency compared to older analog systems.