COMM2_Lesson1_Introduction PDF

Communication 2 Modulation and Coding Techniques INTRODUCTION ENGR. JOMER V. CATIPON Instructor Topics Timeline of Key Milestones in the Shift from Analog to Digital Communication Future of Communications Definition Key Concepts in Digital Communications...

Communication 2 Modulation and Coding Techniques INTRODUCTION ENGR. JOMER V. CATIPON Instructor Topics Timeline of Key Milestones in the Shift from Analog to Digital Communication Future of Communications Definition Key Concepts in Digital Communications Difference between analog and digital communication Why some analog communication systems are still in use Reasons why some analog communication systems are still in use Block diagram of a typical digital communication system  Objectives Identify key milestones in the transition from analog to digital communication. Explore emerging trends and future developments in digital communication technologies. Define the fundamental principles of digital communication. Explain the core concepts that differentiate digital communication from other forms. Compare the characteristics and advantages of digital communication over analog systems. Understand the reasons why certain analog communication systems remain operational today. Describe the components and functionality of a standard digital communication system through its block diagram. Timeline of Key Milestones in the Shift from Analog to Digital Communication  The future of communications 1. 6G Infrastructure and Applications Development Current Situation: 5G is currently being rolled out globally, with most countries still in the early stages of adoption. While it offers significantly faster speeds than 4G, its widespread implementation is hindered by infrastructure costs and regulatory hurdles. Gap: The transition to 6G will require substantial advancements in infrastructure, research on terahertz frequencies, and new hardware to support ultra-high speeds and low-latency applications. What’s Needed: Significant investment in research and development (R&D), partnerships between governments and tech companies, and early standardization efforts to ensure interoperability. Advanced antenna technologies, spectrum allocation, and quantum computing integration are also critical. Advantage: 6G will enable real-time immersive experiences (holographic communication, VR/AR), greater integration of AI in communications, and the creation of smart environments that respond instantly to human and machine interactions.  The future of communications 2. Quantum Communication Network Prototype Current Situation: Quantum communication is in its infancy, with early experiments being conducted in isolated labs. Quantum Key Distribution (QKD) has been demonstrated but is not yet scalable for widespread use. Gap: The challenge lies in scaling quantum communication networks across large distances while maintaining the integrity of quantum signals, as well as making the technology affordable and accessible. What’s Needed: Significant breakthroughs in quantum repeaters and hardware that can transmit quantum signals over fiber-optic networks. Policy frameworks ensuring the ethical use of quantum technology and strong investment in cryptography R&D are required. Advantage: A quantum-secured network would virtually eliminate the possibility of data breaches, leading to ultra-secure communications in industries like finance, government, and healthcare, and significantly reducing the risk of cyberattacks.  The future of communications 3. Holographic Telepresence System Current Situation: Video conferencing tools like Zoom and Microsoft Teams have become essential, especially after the COVID-19 pandemic, but they are limited to 2D screens. Holographic communication exists in theory but is not widely implemented. Gap: Current communication systems do not offer full immersion or the "real presence" needed for high-fidelity interactions. The necessary hardware (cameras, projectors, and bandwidth) for real-time 3D rendering and projection is expensive and not yet common. What’s Needed: Develop cost-effective and accessible hardware capable of capturing and projecting high-resolution holograms. 5G and future 6G networks are essential for the high bandwidth needed. Collaboration between software developers and telecom companies is required. Advantage: Holographic telepresence could revolutionize remote work, global meetings, and virtual education, creating immersive experiences that feel as though participants are physically present, thus enhancing engagement and collaboration.  The future of communications 4. AI-Powered Real-Time Language Translation Current Situation: AI translation tools like Google Translate and Microsoft Translator exist but often struggle with accuracy, context, and nuance, especially for real-time applications like meetings or conferences. Gap: Existing AI models need to be more context-aware, with higher accuracy and faster real- time translation capabilities. Moreover, current hardware isn’t optimized for instantaneous language processing across multiple languages. What’s Needed: Advancements in AI algorithms, especially in neural networks and natural language processing (NLP), are required. Partnerships with linguists and cultural experts can improve contextual understanding. Better hardware for faster AI processing is also needed. Advantage: Real-time translation will break language barriers in global communication, fostering more inclusive collaborations, expanding business opportunities, and enhancing international diplomacy and education.  The future of communications 5. Smart City Communication Platform Current Situation: Cities around the world are beginning to implement smart technology in sectors like traffic management and energy use, but integration across multiple systems is often fragmented and inefficient. Gap: A fully integrated communication platform where every city system can communicate with each other is still lacking. Current IoT networks are not robust enough to handle the vast amount of data generated in real time across an entire city. What’s Needed: Investment in IoT infrastructure, high-capacity networks (5G and 6G), and unified platforms that allow different city systems (transport, energy, waste, etc.) to communicate seamlessly. Data privacy regulations will also need to be strengthened. Advantage: A fully connected smart city would optimize resources (energy, water, transportation), improve public safety and city planning, and create a more efficient, environmentally sustainable urban environment.  The future of communications 6. Global Satellite Internet Connectivity Current Situation: Companies like SpaceX (Starlink) and Amazon (Project Kuiper) are launching satellite constellations to provide global internet coverage, but these services are not yet available to most users, and infrastructure costs remain high. Gap: Despite some success in deploying satellites, there is still a lack of affordable, high-speed internet in many rural or underserved regions globally. Latency issues also persist, especially for real-time communications. What’s Needed: Continued satellite deployment, improved satellite bandwidth, and reductions in latency. Collaboration with governments and local telecom providers will be essential to make satellite internet affordable and accessible. Advantage: Global satellite internet will bridge the digital divide, providing internet access to remote areas, enhancing education, healthcare, and economic opportunities, and contributing to more inclusive global development.  The future of communications 7. Brain-Computer Interface (BCI) Communication Current Situation: BCIs are primarily in the research phase, with some limited applications for controlling prosthetics or aiding disabled individuals in communication. However, commercial and widespread adoption is far from realized. Gap: The technology is currently expensive, invasive (requiring surgery in some cases), and not yet advanced enough to support complex communication or thought-based interaction. What’s Needed: Development of non-invasive BCIs that can accurately interpret brain signals. Greater public acceptance and ethical considerations will need to be addressed. Advancements in AI for interpreting neural activity are also crucial. Advantage: Thought-based communication would revolutionize accessibility for individuals with disabilities, improve human-machine interaction, and open new possibilities for communication, potentially allowing instantaneous transfer of complex ideas without the need for language.  The future of communications 8. Decentralized Communication Network for Privacy Current Situation: Centralized platforms like WhatsApp and Facebook Messenger dominate communication, but concerns over data privacy and security have driven demand for decentralized solutions. Gap: Current decentralized communication tools are limited in usability and scalability. Most people rely on centralized services, and existing blockchain-based communication systems struggle with performance and user-friendliness. What’s Needed: User-friendly decentralized platforms that can handle high traffic while maintaining privacy. Scaling blockchain technologies and improving encryption methods will be essential to make these platforms viable alternatives to centralized systems. Advantage: A decentralized communication network would offer individuals more control over their data, ensuring secure and private communication without relying on third-party companies, thereby reducing risks related to surveillance and data breaches.  The future of communications 9. Wearable Communication Devices Current Situation: Wearable technology like smartwatches and fitness trackers are common, but they are still limited in terms of communication capabilities and are primarily used for notifications or health tracking. Gap: Current wearables are not fully integrated with advanced communication systems like voice assistants, smart textiles, or non-invasive gesture controls. There is also a lack of integration with IoT devices and smart environments. What’s Needed: Advances in flexible electronics, miniaturization of communication modules, and improvements in battery life. Partnerships with fashion and tech industries will be required to develop smart textiles and make wearables more practical for everyday use. Advantage: Wearable communication devices will enable hands-free, always-on communication, improving convenience and accessibility, and seamlessly integrating technology into daily life, particularly in fields like healthcare, business, and personal fitness.  The future of communications 10. Telemedicine Through XR and 5G Current Situation: Telemedicine is growing, particularly after the COVID-19 pandemic, but remote surgeries and real-time, immersive healthcare experiences remain limited by current technology. Gap: Latency and bandwidth issues make real-time remote surgeries impractical. Additionally, XR devices are expensive and not widely used in healthcare settings. Integration with healthcare systems also remains a challenge. What’s Needed: Advanced XR hardware, wider 5G adoption, and specialized telemedicine platforms with strict data privacy protocols. Collaboration between telecom companies, XR developers, and healthcare providers will be essential. Advantage: XR and 5G-based telemedicine would allow for real-time remote surgeries, democratizing access to specialized healthcare professionals. This could be a game-changer for rural or underserved communities, where access to advanced medical care is limited.  Definition Digital communications refer to the electronic transmission of information in digital form between devices or systems. Unlike analog communication, where information is represented by continuous signals, digital communication involves encoding information into discrete binary signals (0s and 1s) that can be easily processed by digital systems.  Key Concepts in Digital Communications Data Encoding: Information (voice, video, text) is converted into a digital format using various encoding schemes, such as PCM (Pulse Code Modulation) or Delta Modulation. Binary Data: The information is represented as a series of binary digits (bits). Modulation: Digital signals are modulated onto carrier waves for transmission over a communication medium (e.g., air, copper wire, fiber optics). Key Modulation Techniques: Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), Phase Shift Keying (PSK), and Quadrature Amplitude Modulation (QAM).  Key Concepts in Digital Communications Transmission Medium: Digital communication can occur over various media, including wired (coaxial cables, fiber optics) and wireless (radio waves, microwaves). Transmission Types: Serial and parallel transmission. Error Detection and Correction: Errors can occur during transmission due to noise, interference, or other factors. Techniques like CRC (Cyclic Redundancy Check), parity checks, and Hamming codes are used to detect and correct errors. Forward Error Correction (FEC) and Automatic Repeat Request (ARQ) are common methods. Protocols: Communication protocols define the rules for data exchange between devices. These include how data is formatted, transmitted, and received. Common Protocols: TCP/IP, Ethernet, Wi-Fi, Bluetooth.  Key Concepts in Digital Communications Bandwidth and Data Rate: Bandwidth refers to the range of frequencies used for communication, while the data rate is the amount of data transmitted per second (bits per second, or bps). Nyquist and Shannon Theorems: These theorems provide theoretical limits on data rates based on bandwidth and noise. Multiplexing: Techniques like Time Division Multiplexing (TDM) and Frequency Division Multiplexing (FDM) allow multiple signals to share the same transmission medium. Digital Signal Processing (DSP): DSP involves manipulating digital signals to improve transmission quality, reduce noise, compress data, etc.  Key Concepts in Digital Communications Applications: Digital communications are used in various applications, including telecommunication networks, computer networks, broadcasting, and mobile communication. Advantages: Higher noise immunity, better error detection and correction capabilities, easier encryption for security, and efficient data compression.  Examples of Digital Communication Systems Cellular Networks: 4G, 5G Wi-Fi: Wireless local area network communication Satellite Communication: Data transmission via satellites Fiber Optic Communication: High-speed data transmission using light pulses through fiber optics VoIP (Voice over Internet Protocol): Digital transmission of voice communications over the internet  Difference between analog and digital communication 1. Signal Representation Analog Communication: Information is represented by continuous signals that vary in amplitude, frequency, or phase over time. These signals are analogous to the original physical quantity (e.g., sound waves, light intensity). Example: A sine wave representing a sound signal. Digital Communication: Information is represented by discrete binary signals (0s and 1s). The original analog signal is sampled, quantized, and then encoded into a digital format. Example: A sequence of binary digits (00101011) representing a digitized sound wave.  Difference between analog and digital communication 2. Transmission Medium Analog Communication: Typically transmitted over media like coaxial cables, twisted pairs, or radio waves with analog modulation schemes (e.g., AM, FM). Digital Communication: Can be transmitted over various media including fiber optics, copper cables, and wireless channels. Digital modulation schemes (e.g., ASK, FSK, PSK) are used to encode binary data onto carrier waves.  Difference between analog and digital communication 3. Bandwidth Usage Analog Communication: Requires a broader bandwidth due to the continuous nature of the signal. The bandwidth depends on the signal’s frequency range. Digital Communication: Can be more efficient in bandwidth usage, particularly with techniques like compression and multiplexing. However, higher data rates require more bandwidth.  Difference between analog and digital communication 4. Noise and Signal Quality Analog Communication: More susceptible to noise and distortion during transmission, which can degrade the quality of the signal. Noise directly affects the signal, causing errors. Digital Communication: More robust against noise because the signal is binary. Even if noise is introduced, the original signal can often be perfectly reconstructed using error detection and correction techniques.  Difference between analog and digital communication Error Detection and Correction Analog Communication: Error detection and correction are challenging since errors directly affect the continuous signal, and there’s no straightforward way to detect or correct errors. Digital Communication: Advanced error detection (e.g., parity checks, CRC) and correction methods (e.g., Hamming code, Reed-Solomon) can be used to identify and fix errors, ensuring more reliable communication.  Difference between analog and digital communication Signal Processing Analog Communication: Processing is done using analog devices like amplifiers and filters. The quality of processing is limited by the precision of analog components. Digital Communication: Digital Signal Processing (DSP) allows for complex operations like filtering, compression, and encryption. Processing is more flexible and can be done with high precision.  Difference between analog and digital communication Transmission Distance Analog Communication: Signal quality deteriorates over long distances due to attenuation and noise. Requires repeaters or amplifiers, but amplifying also amplifies noise. Digital Communication: Digital signals can be transmitted over longer distances with repeaters that regenerate the signal, minimizing the impact of noise and maintaining signal integrity.  Difference between analog and digital communication 8. Complexity and Cost Analog Communication: Generally simpler and less expensive in terms of hardware and implementation. However, scaling up and maintaining quality can be challenging. Digital Communication: More complex and costly initially due to the need for analog-to-digital conversion, modulation, and digital processing. However, it’s more scalable, and the cost has been decreasing over time.  Difference between analog and digital communication 9. Storage and Transmission Analog Communication: Storing analog signals requires magnetic tapes or other continuous media, which are prone to degradation over time. Digital Communication: Digital data can be stored efficiently on various media (e.g., hard drives, flash memory) without quality loss over time, and it can be easily copied and transmitted.  Difference between analog and digital communication 10. Applications Analog Communication: Used in older technologies like AM/FM radio, analog TV, and traditional landline telephones. Digital Communication: Dominates modern technology, used in digital television, mobile phones, the internet, and most modern communication systems. Reasons why some analog communication systems are still in use 1. Legacy Systems Infrastructure: Many analog communication systems, such as AM/FM radio and traditional landline telephones, have extensive infrastructure that has been in place for decades. Replacing or upgrading this infrastructure to digital would be costly and time- consuming. Compatibility: Certain industries and regions continue to rely on analog systems due to compatibility with existing equipment and systems. For example, some aviation and maritime communications still use analog signals to ensure compatibility with older systems. Reasons why some analog communication systems are still in use 2. Simplicity and Cost Lower Complexity: Analog systems are often simpler to design, implement, and maintain. For applications where the requirements are basic, such as intercom systems or simple public address systems, analog communication can be more straightforward and cost- effective. Cost-Effective: In certain cases, the cost of implementing a basic analog communication system can be lower than that of a digital system, especially for small-scale applications that don’t require advanced features. Reasons why some analog communication systems are still in use 3. Real-Time Communication Low Latency: Analog systems typically introduce less latency than digital systems, which is advantageous in applications where real-time communication is critical, such as in live audio transmissions for concerts or radio broadcasts. Reasons why some analog communication systems are still in use 4. Niche Applications Specific Needs: Some specialized applications still rely on analog communication because it meets specific needs better than digital systems. For instance, certain types of scientific measurements or sensor data that are inherently analog may be easier to handle in analog form. Audio Quality: Some audiophiles and professionals in the music industry prefer analog systems, such as vinyl records or analog audio equipment, due to the perceived warmth and natural quality of analog sound. Reasons why some analog communication systems are still in use 5. Robustness in Certain Environments Resilience to Harsh Conditions: In some environments, particularly those with extreme noise, interference, or where signal processing and error correction are challenging, analog signals may be more resilient. For example, in some underground or remote communication systems, analog signals can be more reliable. Simpler Repair and Maintenance: Analog equipment can sometimes be easier to repair in the field, especially in remote or underdeveloped areas where access to advanced digital repair tools and expertise might be limited. Reasons why some analog communication systems are still in use Broadcasting and Coverage Wide Coverage Area: Analog broadcasting, such as AM radio, can cover large geographical areas, making it ideal for rural or remote regions where digital infrastructure is sparse or nonexistent. Community Broadcasting: In some parts of the world, community radio stations use analog transmission due to its simplicity and the low cost of operation, allowing them to serve local populations effectively. Reasons why some analog communication systems are still in use Regulatory and Licensing Factors Regulatory Requirements: In some regions, regulatory bodies may still allocate certain frequencies for analog communication, particularly in public safety or emergency services. Licensing and Spectrum Use: Existing licenses for analog communication may be easier or cheaper to maintain than acquiring new digital licenses, especially in crowded spectrum environments. Reasons why some analog communication systems are still in use Cultural and Historical Value Cultural Significance: Certain forms of analog communication, such as shortwave radio or vinyl records, have cultural or historical significance that keeps them in use despite the availability of digital alternatives. Historical Preservation: Analog media and communication methods are sometimes maintained for archival purposes, to preserve the authenticity of historical recordings and broadcasts. Model of an Electronic Communications System Elements of Digital Communication  Block diagram of a typical digital communication system 1. Information Source Function: The information source generates the original message or data that needs to be transmitted. This could be anything from text, audio, video, or any other form of data. What Happens: The source creates the information in its natural form, which is typically analog (e.g., human voice, video). Example: A person speaking (audio signal), a video camera recording a scene, or a computer generating a digital file. Associated Terms: Data, message, signal.  Block diagram of a typical digital communication system 2. Input Transducer Function: Converts the analog signal from the information source into an electrical signal that can be processed by the system. What Happens: The input transducer converts physical signals (e.g., sound waves) into electrical signals. For digital communication, this electrical signal may then be digitized. Example: A microphone converting sound waves into an electrical signal, a camera sensor converting light into an electrical signal. Associated Terms: Analog-to-digital conversion (if digitization occurs immediately after), transduction, sensor.  Block diagram of a typical digital communication system 3. Source Encoder Function: Compresses and encodes the information signal to reduce redundancy and prepare it for efficient transmission. What Happens: The signal is encoded into a digital format, often involving compression techniques that reduce the size of the data while retaining the essential information. Example: Converting an audio signal into a compressed digital format like MP3, encoding video into H.264 format, or using Huffman coding for text data. Associated Terms: Data compression, quantization, entropy coding, sampling (if digitization happens here).  Block diagram of a typical digital communication system 4. Channel Encoder Function: Adds redundancy and error-correcting codes to the encoded data to protect against errors during transmission. What Happens: The signal is encoded with additional bits (error correction codes) that allow the receiver to detect and possibly correct errors that occur during transmission. Example: Adding parity bits, using Hamming code, Reed-Solomon coding, or convolutional coding. Associated Terms: Error detection, error correction, forward error correction (FEC), redundancy.  Block diagram of a typical digital communication system 5. Channel Function: The medium through which the encoded signal is transmitted from the transmitter to the receiver. What Happens: The signal travels through the physical medium, which could introduce noise, distortion, and other impairments. Example: Transmission through the air (radio waves), through a fiber optic cable, or over the internet. Associated Terms: Noise, attenuation, interference, signal-to-noise ratio (SNR), bandwidth, modulation.  Block diagram of a typical digital communication system 6. Channel Decoder Function: Decodes the received signal, detecting and correcting errors introduced during transmission. What Happens: The decoder analyzes the received signal, uses the redundancy added by the channel encoder to detect and correct errors, and reconstructs the original encoded signal. Example: Using error correction algorithms like Reed-Solomon decoding, Viterbi algorithm for convolutional codes. Associated Terms: Error correction, decoding, syndrome, cyclic redundancy check (CRC).  Block diagram of a typical digital communication system 7. Source Decoder Function: Decompresses and decodes the signal to restore the original information format. What Happens: The compressed and encoded signal is decoded and decompressed to retrieve the original data as closely as possible to its original form. Example: Converting an MP3 file back into a waveform, decoding H.264 video into a viewable format. Associated Terms: Decompression, decoding, reconstruction, inverse quantization.  Block diagram of a typical digital communication system 8. Output Transducer Function: Converts the electrical signal back into a form that can be perceived by the receiver, typically back into its original analog form. What Happens: The decoded electrical signal is converted into a physical signal that the receiver can sense, such as sound or light. Example: A speaker converting an electrical signal into sound waves, a display converting electrical signals into visual images. Associated Terms: Digital-to-analog conversion (if applicable), actuator, transduction.  Block diagram of a typical digital communication system 9. Receiver Function: The end device or system that processes the received signal and presents the original information to the user. What Happens: The receiver gathers the output from the output transducer and presents it in a user-friendly format. Example: A mobile phone receiving a call, a TV set displaying video, or a computer playing back audio. Associated Terms: Terminal equipment, user interface, playback, display.  Signal Flow Summary Information Source generates the original data (e.g., a voice speaking). Input Transducer converts this data into an electrical signal (e.g., microphone converts sound to an electrical signal). Source Encoder compresses and digitizes the signal (e.g., audio is encoded into MP3 format). Channel Encoder adds error correction codes to protect the signal during transmission. The signal is transmitted through the Channel (e.g., airwaves, fiber optics) to the receiver. Channel Decoder processes the received signal, correcting any errors. Source Decoder decompresses and decodes the signal to retrieve the original information. Output Transducer converts the electrical signal back into a perceivable form (e.g., speaker produces sound). The Receiver presents the final output to the user.