Communication Technologies

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  1. Information and Communication
  2. Mediums of communication
    1. Differences between Broadcasting, Social and Personal Media
    2. Terminologies related to web media
      1. Web services
      2. Difference between XML, HTTP and HTML
      3. Web Services Technologies
      4. Service Oriented Architecture
      5. RSS 
      6. Social Media Related Terms
  3. Communication Technologies
    1. Satellite Communication
    2. Navigation systems
    3. Telephones
    4. Mobile phones
      1. Cellular system concept
      2. Multiplexing
      3. Communication Standards
      4. Technologies – GPRS and 5G
    5. Internet
      1. Internet Protocols
      2. World Wide Web
      3. Types of Networks
    6. Quantum communication
    7. Molecular Communication
    8. Machine to Machine(M2M) Communication
      1. Internet of Things
  4. Methods of transmission
    1. Wired
    2. Wireless
      1. Global Internet Connectivity Projects
  5. Miscellaneous
    1. Ham Radio
    2. Podcasting
  6. FAQs
    1. What is a broadband?

1. Information and Communication

Collection and use of information is an essential process in human civilisation.

  • Information is nothing but organised data”
  • Data is simply a collection of facts.
  • The understanding of information is “knowledge”

Now a days the the knowledge economy makes up a large share of all economic activity in many economies.

Information Revolution

Even though the technological developments started in 1800s, the recent information revolution is result of the development of technologies (such as computers, digital communication, microchips) in the second half of the 20th century.

  • Information revolution has led to dramatic reduction in the cost of obtaining, processing, storing, and transmitting information in all forms (text, graphics, audio, video).
  • The main feature of the information revolution is the growing economic, social and technological role of information.

Communication

Communication is the transmission of information. It can be achieved through various methods, mediums and technologies.

2. The mediums of communication

A medium is a channel or system of communication. It can be broadly classified as

  1. Broadcasting Media
  2. Social Media
  3. Personal Communication

2.1 The differences between different mediums of communication

Medium Characteristics Examples
Broadcasting
  • Message is distributed
  • Typically electromagnetic Spectrum is used
Television

Satellite broadcasting

Webcasting

Social Media
  • Are interactive
  • Mainly internet based
  • Has user generated contents
Facebook

Twitter

Google+

Wikipedia

LinkedIn

Pinterest

Myspace

Personal Only the message senders and the message receivers understand the message even though it may be transmitted over the same medium used for broadcasting E-mail

WhatsApp

SMS

Telephone

Mobile phone

2.2 Terminologies related to Web Media

2.2.1 Web Services

There are various software applications written in various programming languages and running on various platforms. The interoperability between the languages and platforms are essential for those applications to be a part of the internet. Web services are used to exchange data over computer networks.

  • A web service is any piece of software that makes itself available over the internet and uses a standardized messaging system.
  • They are not tied to any one operating system or programming language.
  • They are built on top of open standards such as TCP/IP, HTTP, Java, HTML, and XML.
  • Using web services, Java can talk with Perl; Windows applications can talk with Unix applications. The interoperability is due to the use of open standards.

The basic web services platform is XML + HTTP. 

2.2.2 What is the difference between XML, HTTP and HTML?

Extensible Markup Language (XML)

  • Is used to describe data
  • Is a flexible way to create information formats and electronically share structured data via the public Internet
  • XML is used to encode all communications to a web service
  • encodes documents in a format that is both human-readable and machine-readable.
  • An example of  XML code is 

<conversation>

<greeting>Hello, world!</greeting>

<response>Hello </response>

</conversation>

Hyper Text Transfer Protocol(HTTP)

  • Is the underlying protocol used by the World Wide Web 
  • It defines how messages are formatted and transmitted
  • It defines what actions Web servers and browsers should take in response to various commands
  • Example of a HTTP code
    GET /IES.htm HTTP/1.1
    User-Agent: Mozilla/4.0 (compatible; MSIE5.01; Windows NT)
    Host: www.iesgeneralstudies.com
    Accept-Language: en-us
    Accept-Encoding: gzip, deflate
    Connection: Keep-Alive

Hypertext Markup Language (HTML)

  • Is the standard markup language for creating web pages and web applications.
  • Covers how Web pages are formatted and displayed
  • An example for HTML code

<head>

<title>Home Page</title>

</head>

<body>

Here are the Dynamic and Static Subjects

</body>

</html>

2.2.3 Web Services Technologies(WST)

  • A collection of XML technology standards that work together to provide Web Services
  • Are primarily an integration or interfacing technology, not an application development technology
  • It can be used to implement the interfaces and messages for a Service Oriented Architecture (SOA)
  • The examples of WSTs are,
    • XML Technologies (Extensible Markup Language) – standards for documents
    • SOAP (Simple Object Access Protocol)  – provides a  simple way to send documents
    • WSDL(Web Services Description Language) – defines all details about a service
    • UDDI(Universal Description, Discovery and Integration)– is a way to advertise and discover services

2.2.4 Service Oriented Architecture (SOA)

  • Is a style of software design 
  • Is essentially a collection of services
  • Examples of services are  – producing data, validating a customer, providing simple analytical services
  • These services operate independently and can interact with each other
  • Are independent of vendors, products and technologies

2.2.5 RSS

  • Is used for distributing Web content in feeds as opted by users.
  • Feeds allow the users to have new content delivered to a computer or mobile device as soon as it is published.
  • An RSS aggregator or RSS reader provides the feeds.
  • Instead of visiting multiple Web pages to check for new content, the user can look at the summaries and choose which sites to visit for the full versions
  • News discussion forum excerpts, software announcements, blog posts, podcasts and any form of content retrievable with a URL can be included in RSS feeds
  • Is XML(Extensible Markup Language) based standard
  • RSS is an abbreviation for describing one of three different standards, which include:
    • RDF Site Summary (RSS .9 and 1.0) (RDF- Resource Description Framework)
    • Rich Site Summary (RSS 0.91 and 1.0)
    • Really Simple Syndication (RSS 2.0)

 

2.2.6 Social Media Related Terms

  • Social media analytics – gathering data from blogs and social media websites and analyzing that data to make business decisions.
  • Social media marketing – uses social networking to increase brand exposure and broaden customer reach. Social media optimization is done by
    • Using RSS feeds and sharing buttons
    • Through social media posts
  • Social CRM (customer relationship marketing) – is powerful business tool using social media to create better customer relations. It is a venue for communication, marketing and networking and feedbacks.
  • Crowdsourcing –  usually involves doing business or projects with inputs from internal and external actors, including  inputs from customers and or the general public. “Wikipedia” is the most famous example of crowd sourcing.

Image from: http://www.optimizationgroup.com/

 

3. Communication Technologies

Is the infrastructure and components that enable the communications. Some of the technologies are

  1. Satellite Communication
  2. Navigation systems
  3. Telephones
  4. Mobile phones
  5. Internet 
  6. Quantum communication
  7. Molecular Communication
  8. Machine to Machine Communication

3.1 Satellite Communication

  • Satellites communicate by using radio waves to send signals to the antennas on the Earth.
  • The antennas then capture those signals and process the information coming from those signals, via a transponder thus creating a communication channel with ground stations.

What are radio waves?

  • The basic building block of radio communications is a radio wave.
  • Like waves on a pond, a radio wave is a series of repeating peaks and valleys.
  • A radio wave is generated by a transmitter and then detected by a receiver.
  • An antenna allows a radio transmitter to send energy into space and a receiver to pick up energy from space.

Applications:

  • Used for such diverse applications like Television, DTH Broadcasting, DSNG( digital satellite news gathering) , VSAT(very small aperture terminal ) communication, Positioning services  and satellite phones

Satellites use different, higher radio frequencies as follows

Image source: http://www.esa.int/

Frequency Bands Characteristics Applications
L-band

(1-2 GHz)

 Useful for mobile applications such as maritime and aeronautical uses

 

Used in GPS, satellite phones 
S-band

(2-4 GHz)

Capable of supporting high data rates

Has higher power

 Radar applications

Communications with space stations

C-band

(4-8 GHz)

Reach over wide geographic areas

perform better under adverse weather conditions

Requires larger ground equipments

Has low power

Full-time satellite TV networks

Satellite feeds 

X Band

(8-12 GHz)

Helpful for weather monitoring, air traffic control, maritime vessel traffic control, and vehicle speed detection   Primarily used for military applications
 Ku-band

(12-18 GHz)

 Higher transmission power

Requires smaller ground equipments

Reach over only smaller geographic areas

Direct broadcast satellite services 
Ka-band

(26-40 GHz)

Higher transmission speed

Significant information transfer

Requires smaller ground equipments

High-resolution

Communications satellites

3.2 Navigation systems

Navigation is the science of finding a way from one place to another. The present navigation systems typically uses a satellite navigation device .The navigation systems existing at present are,

Navigation Systems Whose? Characteristics
GPS USA Operational since 1978 and globally available since 1994, GPS is currently the world’s most utilized satellite navigation system

Uses up to 32 satellites

GLONASS Russia Has global coverage

Uses 24 satellites

BeiDou China Regional network

To be expanded into the whole globe as BeiDou-2 with 35 satellites

GALILEO EU Is expected to be in full service in 2020
NAVIC India Regional network using 7 satellites

Expected to be fully operational soon

QZSS Japan Regional network under development using 3 satellites

How Position is determined?

Trilateration Method

Image source: http://gisgeography.com/

  • The time taken by signals from three satellites to reach the location is used
  • The required location is where three spheres created by distance from each of three satellites as radius, overlap.
  • A fourth satellite is used to double-check  the location
  • In contrast to triangulation, it does not involve the measurement of angles

3.4 Mobile phones

Any radio telephone capable of operating while moving at any speed, and small enough to be carried by a person comes under the mobile communication systems. Mobile phone system was the commercially introduced in 1983. Since then mobile communication systems have witnessed an explosive growth.

3.4.1 Cellular System Concept

Image source: http://people.seas.harvard.edu/

  • The service area is covered by geographic cells.
  • The frequency spectrum is divided into discrete channels and assigned in groups to these geographic cells
  • The discrete channels are capable of being reused in different cells
  • The adjacent cells operate on different frequencies to avoid interference.

3.4.2 Multiplexing

Multiplexing (or muxing) is a way of sending multiple signals or streams of information over a communications link at the same time in the form of a single, complex signal. The receiver recovers the separate signals, a process called demultiplexing (or demuxing).

So, this is a  technique used to send multiple signals over a single channel. It can be carried out in three dimensions: Time (TDMA), frequency (FDMA, OFDMA) and code (CDMA).

Need for multiplexing

  • To make it possible for any network device to talk to any other network device without having to dedicate a connection for each pair. This requires shared media
  • To make a scarce or expensive resource stretch further — e.g., to send many signals down each cable or fiber strand running between major metropolitan areas, or across one satellite uplink.

TDMA 

Mechanism:

  • It allows several users to share the same frequency channel by dividing the signal into different time slots. 
  • The users transmit in rapid succession, one after the other, each using its own time slot.
  • This allows multiple stations to share the same transmission medium (e.g. radio frequency channel) while using only a part of its channel capacity.

Uses:

  • It is commonly used in digital transmission such as Global System for Mobile communication(GSM).
  • The multiple signals are carried over the same channel in alternating time slots.

A disadvantage of TDMA systems is that they create interference at a frequency which is directly connected to the time slot length.

FDMA 

  • Commonly used in analog transmission.
  • Communications link is divided into sub channels of different frequency widths, each carrying a signal at the same time.
  • It is particularly used in satellite communication

CDMA 

Mechanism:

  • Audio input is first digitized into binary elements.
  • The frequency of the transmitted signal is then made to vary according to a defined pattern (code), so it can be intercepted only by a receiver whose frequency response is programmed with the same code
  • So the receiver can follow exactly the transmitter frequency as per the code.

Advantages:

  • There are trillions of possible frequency-sequencing codes, which enhances privacy and makes cloning difficult.
  • Multiple communications can be sent over the same channel

3.4.3 Communication Standards

GSM

  • Global system for mobile communications (GSM) was developed by the Groupe Special Mobile in 1991
  • Originally it was 2G standard 
  • Initially based on TDMA
  • 3G version of GSM uses CDMA technology also

LTE

  • Stands for Long Term Evolution
  • Increases bandwidth available for voice and data communications
  • Comes with a number of network improvements
  • It’s the upgrade path for both GSM and CDMA based networks
  • LTE is commonly marketed as 4G LTE

AWS

  • Advanced Wireless Services
  • Also referred to as UMTS(Universal Mobile Telecommunications System) band IV
  • Uses microwave frequencies in two segments: from 1710 to 1755 MHz for uplink, and from 2110 to 2155 MHz for downlink

1G to 5G

Image from: www.slideshare.net

  Characteristics Uses
1G Analog technology Released in 1990 to be used in GSM
2G Digital

Uses encryption

There were GSM and CDMA versions

Enables text and multi media messages
2.5G Combined with GPRS technology(a packet-based wireless communication service) Users can take part in video conferences and interact with multimedia web sites
3G Introduced higher transfer rates Supports simultaneous voice and data

Can handle complex data such as video

Faster communication and web streaming

4G Mobile broadband internet services provided to external systems, such as laptops, wireless modems, etc

Additional features such as IP telephony, ultrabroadband Internet access, gaming services and HDTV streamed multimedia

100Mbps to 1Gbps speed

Any kind of service at anytime anywhere as per user requirements
5G High speed(download speeds of 20 GBs/second)

High capacity

HD video quality

Can support WWWW(wireless world wide web)

Address network congestion, energy efficiency, cost, reliability, and connection to billions of people and devices

VoLTE

  • stands for voice over LTE
  • It’s voice calls over a 4G LTE network
  • call quality is superior to 3G or 2G connections as far more data can be transferred over 4G 
  • can make and receive video calls from anyone else with VoLTE, rather than relying on separate accounts like skype

3.4.4 Technologies – GPRS and 5G

GPRS technology

  • GPRS was one of the first technologies that enabled a cell network to connect with Internet Protocol (IP) networks
  • Enabled Web browsing from a phone 
  • Uses packet switching for data transmission
  • Is gradually being phased out in favour of newer 3G/4G installations
  • EDGE (Enhanced Data rates for GSM Evolution) technology was the enhanced version of GPRS

5G Technology

Image source: IEEE

The 5G is a technology that will run the next wave of fast mobile broadband networks in possibly two years from now. The different techniques under development are,

a. Millimetre-Wave technologies

  • Airwaves in the 3500 MHz band are considered ideal for the first wave of 5G
  • 5G networks can run on the 3400 MHz, 3500 MHz and 3600 MHz spectrum bands.
  • A key challenge is the possibility of millimetre waves being blocked by buildings and losing their intensity over longer distances, can also be absorbed by foliage and rain

b. Small Cell Networks

  • Thousands of low power mini base stations
  • can  take advantage of another new technology called massive MIMO

c. Massive MIMO

  • Multiple input to multiple output to handle more traffic means use two or more transmitters and receivers to send and receive more data at once
  • 5G base stations can support about a hundred ports, which means many more antennas can fit on a single array

d. Beam Forming

  •  is a traffic-signaling system to  identify the most efficient data-delivery route to a particular user
  • rather than broadcasting in many directions at once, this approach can strengthen the signal’s chances of arriving intact and reduce interference

e. Full Duplex

  • a transceiver will be able to transmit and receive data at the same time, on the same frequency
  • silicon transistors that act like high-speed switches enables transmission and reception of signals on the same frequency at once

3.4 Telephones

  • Transmits signals converted from audio data through physical media, such as wire or fibre optic cable
  • Two basic types are corded and cordless
  • With advances in mobile communications, users now rely solely upon cellular phone service, resulting in a sharp reduction in the numbers of landline subscribers

3.5 Internet

  • Internet is essentially a network of computers. 
  • Internet uses the same public telecommunication networks. But the difference is,  Internet uses of a set of protocols called TCP/IP (Transmission Control Protocol/Internet Protocol).

3.5.1 Internet Protocols

  • TCP and IP are two distinct protocols (A protocol means an agreed-upon set of procedures and rules)
  • When two computers follow the same protocols, they can understand each other and exchange data
  • TCP/IP functionality is divided into four layers, each with its own set of agreed-upon protocols
Layers Protocols Functions
The Datalink Layer Ethernet and ARP  Operate on a link that interconnects nodes or hosts in the network
The  Internet or Networking layer IP and ICMP.  Connects independent networks to transport the packets containing the data
The  Transport layer TCP and UDP  Handles communications between hosts, flow control, multiplexing
The  Application layer  HTTP, FTP, POP3, SMTP, and SNMP  Data exchange for applications

TCP (Transmission Control Protocol)

TCP governs how to divide a message or file into packets that are transmitted over the internet and then how they are reassembled when they reach their destination. 

IP(The Internet Protocol)

  • Internet Protocol is responsible for the address of each packet.
  • Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet. 
  • Each packets contains both the sender’s Internet address and the receiver’s address. 
  • The most widely used version of IP today is Internet Protocol Version 4 (IPv4) having 32 bits address
  • IPv6 is designed to anticipate enormous future expansion in the number of available IP addresses
  • IPv6 provides for much longer addresses (128 bits)
  • IPv6 also supports auto-configuration to help correct most of the shortcomings in version 4, and it has integrated security and mobility features.

Ethernet

  • Ethernet is the most widely installed local area network (LAN) technology.
  • Describe how networked devices can format data for transmission to other network devices and how to put that data out on the network connection.
  • It touches both Layer 1 (the physical layer) and Layer 2  (the data link layer) on the OSI network protocol model.
  • Ethernet defines two units of transmission, packet and frame.
  • Each frame is wrapped in a packet.

3.5.2 World Wide Web

  • The most widely used part of the Internet is the World Wide Web
  • Hypertext was the main concept that led to the invention of the World Wide Web
    • Hypertext is a method of instant cross-referencing.
    • It is the organization of information units into connected associations that a user can choose to make.
    • Example, is a link or hypertext link. 
  • So internet is nothing but an enormous amount of information content, connected by an enormous number of hypertext links
  • Web browsing is done with a Web browser, the most popular of which are Chrome, Firefox and Internet Explorer.

3.5.3 Types of networks

As per the size, capability and geographical coverage, the networks are

  1. LAN – within a office building or home
  2. MAN – spans a city or large campus
  3. WAN – can cover even whole of the world
  4. PAN – within a room

3.6 Quantum communication

Quantum communication uses properties of quantum particles for a secure and fast communication system. The Quantum cryptography is one of its applications.

Quantum Cryptography

  • Is used to make a secure communication using QKD(quantum key distribution)
  • Uses the quantum properties of the photons to detect eavesdropping
  • The photons generated by a single photon source are encoded into binary values(qubits) and transmitted to the receiver . The receiver then decodes the state of photons.
  • The presence of an eavesdropper is revealed by the imperfect correlation between the two lists of bits obtained after the transmission of qubits between the emitter and the receiver.

Quantum Teleportation

  • Teleportation is the theoretical transfer of matter or energy from one point to another without traversing the physical space between them. 
  • Quantum teleportation is possible using a process called ‘Quantum Entanglement
  • The particles share their ‘quantum states’ — such as energy, motion and magnetic field — regardless of the distance separating them.
  • If one particle changes, its co particle in the other location also changes
  • It can be the basis of futuristic quantum internet, quantum information technology, quantum computing etc
  • Micius is the the world’s first quantum-enabled satellite launched by China in 2016
  • Chinese researchers successfully teleporting a photon from an instrument on the Tibetan plateau to Micius in 2017

3.7 Molecular Communication

  • Is a Nano network design strategy where a transmitter emits information molecules .
  • Takes inspiration from some existing communication mechanisms between biological entities.
  • Bio-nanomachines (e.g., artificial cells, genetically engineered cells) are used .
  • Biological molecules acts both as carriers and as information.
  • Examples of applications are drug delivery system (DDS), bio-hybrid implants, and lab-on-a-chip (LoC) systems. 

3.8 Machine to machine (M2M) communication

  • Refers to direct communication between devices using any communications channel, including wired and wireless
  • Key components of an M2M system include sensors, RFID, a Wi-Fi or cellular communications link and autonomic computing software
  • The devices have ability to transfer data over a network without requiring human-to-human or human-to-computer interaction. 
  • The most well-known type of M2M communication is telemetry(transmission of performance measurements from monitoring instruments in remote locations)
  • Products built with M2M communication capabilities are often marketed as “Smart”
  • It forms the basis for the concept of the Internet of Things (IoT)

3.8.1 Internet of Things(IOT)

Image source: Wikipedia

  • The Internet of Things is about connecting internet-enabled devices to cloud-based applications and to each other.
  • The devices can be anything from mobile phones, fridges, washing machines to wearables, medical equipment or jet engines. 
  • IoT has evolved from the convergence of wireless technologies, micro-electromechanical systems (MEMS), micro services and the internet.
  • IoT use the web and unique identifiers such as RFID tags or processors in order to be part of the internet.
  • IPv6’s huge increase in address space, which could provide unique address for each device, is an important factor in the development of the Internet of Things. 
  • The devices have ability to transfer data over a network without requiring human-to-human or human-to-computer interaction. 

IOT Applications

Internet of Things can connect devices embedded in various systems to the internet. Thus they can be controlled from anywhere. This connectivity helps to capture more data from more places, and helps in increasing efficiency and improving safety & security. Some of the applications are,

Business

  • Power utilities, oil & gas, insurance, manufacturing, transportation, infrastructure and retail sectors etc can reap the benefits of IoT by making more informed decisions
  • can help organizations reduce cost through improved process efficiency, asset utilization and productivity
  • can benefit from real-time insights and analytics, which would help them make smarter decisions

Smart Homes

  • with connected devices which can be controlled from mobile phones
  • better security

Health Care

  • smart mointors, remote monitoring
  • smart implants
  • smart beds

Smart Wearables

  • smart watches
  • smart clothes

Smart City

  • Includes a wide variety of uses, from traffic management to water distribution, to waste management, urban security and environmental monitoring.
  • Promise to alleviate the urban problems.
  • Can help make cities safer.

Smart Grids

  • promises to use information about the behaviors of electricity suppliers and consumers in an automated fashion to improve the efficiency, reliability, and economics of electricity

Automobiles

  • driverless cars
  • connected cars

Smart farming

  • Due to the remoteness of farming operations and the large number of livestock that could be monitored the Internet of Things could revolutionize the way farmers work.

4. Methods of Transmission

There are mainly two types of transmission – one using a physical structure and another using electromagnetic waves as carriers

4.1 Wired

Wired connected uses different types of cables. The different types are,

a. Cable-Modem 

  • Modem provides bidirectional data communication from the cables.
  • Coaxial cable is the kind of copper cable used by cable TV companies.

b.DSL (Digital Subscriber Line)

  • Is a technology for bringing high- bandwidth information over ordinary copper telephone lines.
  • xDSL refers to different variations of DSL, such as ADSL, HDSL, and RADSL. 
  • Twisted pair cable is used. 

c. Optical Fibre 

  • It contains strands of glass fibers inside an insulated casing.
  • The center of each strand is called the core, which provides the pathway for light to travel.
  • The core is surrounded by a layer of glass called cladding that reflects light inward to avoid loss of signal and allow the light to pass through bends in the cable(Total Internal Reflection).
  • Can support ultrafast broadband communication .
  • Single mode fiber networks often use Wave Division Multiplexing (WDM) techniques to increase the amount of data traffic
  • WDM allows light at multiple different wavelengths to be combined (multiplexed) in a single light pulse.

4.2 Wireless

Uses electromagnetic waves. Satellite communications and mobile communications were discussed above. The other methods include,

a. Wi-Fi

  • Low power wireless communication
  • Uses radio waves in frequencies of between 2.5 and 5 gigahertz (GHz)
  • Uses wireless network standards known as the 802.11 family

b. Bluetooth Technology 

  • Permits connection to various electronic devices to a system
  • Used for the transferring of data
  • Uses short-wavelength UHF radio waves in the ISM band from 2.4 to 2.485 GHz

c. WiMax  

  • Is a technology standard for long-range wireless networking, for both mobile and fixed connections. 
  • WiMAX was once envisioned to be a leading form of internet communication as an alternative to cable and DSL, but its adoption has been limited

d. RFID 

  • Uses electromagnetic fields to automatically identify and track tags attached to objects.
  • The tags contain electronically stored information.
  • Uses radio waves
  • Serves the same purpose as a bar code or a magnetic strip 

e. NFC(Near Field Communication)

  • Evolved from radio frequency identification (RFID) technology
  • Enable two electronic devices, to establish communication by bringing them within 4 cm of each other
  • Now a days used in digital transactions as contactless payment system

f. Li-fi 

  • Use  the visible light portion of the electromagnetic spectrum to transmit information at very high speeds
  • Can use common household LED (light emitting diodes) light bulbs and supports speed to 224 gigabits per second
  • Electricity supplied to an LED light bulb can be dipped and dimmed, up and down at extremely high speeds, without being visible to the human eye.
  • Li-Fi signals cannot pass through walls

4.2.1 Global Internet Connectivity Projects

Microsoft’s White-fi Project

  • Use the TV unused spectrum, or TV white space
  • It creates wireless local area network (WLAN) in TV white space spectrum in the ultra-high frequency (UHF) band between 470 MHz to 700 MHz
  • Microsoft is working with the government to make White-Fi a viable technology for the Indian landscape

Google’s Project Loon

  • Uses High altitude balloons placed in the stratosphere at an altitude of about 18 km
  • These balloons are used to create an aerial wireless network 
  • Can support speeds up to 4G-LTE standards
  • Project being developed by Google to provide Internet access to rural and remote areas
  • Google claims that, with an accurate enough model of wind speeds and directions, it is possible to effectively direct the balloons simply by raising or lowering their altitude to ensure they blow in the desired direction.
  • Project Loon was first tested in New Zealand in 2013

Face Book’s Solar Drones

  • Drones are used to provide wireless connections
  • Facebook‘s solar drone is named ‘Aquila’
  • Is a lightweight but wide, solar-powered aircraft which able to fly without landing for three months at a time
  • Uses a laser to beam data to a base station on the ground. 

5. Miscellaneous

5.1 Ham Radio

Amateur radio (also called ham radio) describes the use of radio frequency spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency communication. The term “amateur” is used to specify “a duly authorised person interested in radioelectric practice with a purely personal aim and without pecuniary interest

Licence

The amateur radio service (amateur service and amateur-satellite service) is established by the International Telecommunication Union (ITU) through the International Telecommunication Regulations. National governments regulate technical and operational characteristics of transmissions and issue individual stations licenses with an identifying call sign

What can I do with it?

Ham radio is basically a social hobby — whether you’re talking around town, around the world, at club meetings or conventions, you’ll be getting to know some pretty darn nice people!

  • Talking around the world without wires.
  • Talking locally through repeaters.
  • Emergency communications.
  • Public service communications, etc

5.2 Pod Casting

  • Podcasting is the preparation and distribution of audio files using RSS to the computers of subscribed users. 
  • A podcast can be easily created from a digital audio file(mp3)
  • The MP3 file gets its own URL, when it is uploaded to the Web site of a service provider
  • The URL is inserted into an RSS XML document, which can be subscribed by users
  • Similar to subscription-based interactive television service that lets viewers program and control which television shows they watch, and when. 

Advantages

  • allows users to listen to their selected podcasts whenever they like
  • because of the portability of the player devices, users can listen to audio files from the Internet as they go about their daily activities
  • is an inexpensive and user-friendly new distribution channel that has the potential to reach a large audience
  • musicians and bloggers are the early adopters, now mainstream media organizations are beginning to venture into podcasting 

 

6. FAQs

What is a broad band?

In general, broadband refers to telecommunication in which a wide band of frequencies is available to transmit information. Because a wide band of frequencies is available, information can be multiplexed and sent on many different frequencies or channels within the band concurrently, allowing more information to be transmitted in a given amount of time.

 

15 Comments

  1. sandeep says:

    bhai iske alawa or kuch bhi h kya ict k static part me?

  2. ashish says:

    very helpful sir
    Thank You

  3. Rajesh Sahu says:

    unbelieveable step taken by u sir….it means a lot to the aspirants to get so many information at one place sitting t home….thank u a lot sir…
    plz do help us by provideing the valuable study materials…

  4. Tinku Sharma says:

    remarkable effort by you sir
    sir can you provide the pdf for the above content it will be very beneficial …..as it strains the eyes reading on laptop

  5. Ankit says:

    Sir ,Outstanding amount of work done by you
    Where is the quiz for this article?
    Quizzes help to digest the article completely.
    Please upload sir.

  6. faizan says:

    great effort ….may ALMIGHTY bless you

  7. SUMAN KUMAR says:

    Quiz nahi sir…

  8. NAGA says:

    Great effort sir.

  9. Sneha says:

    Sir, quiz on the chapter isn’t there.
    Thank you for the website. It’s a great one.

  10. TRINAYAN BORAH says:

    it is asuch a pleasure to read the passages….supurb work sir

  11. abhishek rawat says:

    i think the material provide is not sufficient for ies ,,, so plz provide better data

  12. Harsh says:

    Thank You Sir !

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