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1. Art & Culture Sample
Covered under topic 1. Indian culture will cover the salient aspects of Art Forms, Literature and Architecture from ancient to modern times.
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1. Indian culture will cover the salient aspects of Art Forms, Literature and Architecture from ancient to modern times. (copy)
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2. Modern Indian history from about the middle of the eighteenth century until the present- significant events, personalities, issues. (copy)
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5. History of the world will include events from the 18th century such as Industrial revolution, World wars, Redrawal of national boundaries, Colonization, Decolonization, Political philosophies like Communism, Capitalism, Socialism etc.- their forms and effect on the society.
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7. Role of women and women’s organizations, Population and associated issues, Poverty and developmental issues, Urbanization, their problems and their remedies.
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10.2. Introduction to Maps
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GS2
All topics that need updates are given below.
2. Functions and responsibilities of the Union and the States, issues and challenges pertaining to the federal structure, devolution of powers and finances up to local levels and challenges therein.
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5. Parliament and State Legislatures – structure, functioning, conduct of business, powers & privileges and issues arising out of these.
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6. Structure, organization and functioning of the Executive and the Judiciary; Ministries and Departments of the Government; pressure groups and formal/informal associations and their role in the Polity.
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12. Welfare schemes for Vulnerable Sections of the Population by the Centre and States and the Performance of these schemes; Mechanisms, Laws, Institutions and Bodies constituted for the Protection and Betterment of these Vulnerable Sections.
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GS3
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11. Science and Technology- developments and their applications and effects in everyday life.
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GS3: BIODIVERSITY AND ENVIRONMENT
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1. Environment
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GS4
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GS3: SCIENCE AND TECHNOLOGY
All topics given below
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1. Motion & Measurements
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9. Metals & Non-Metals
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10. Energy
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12. Plant Organisms
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14. Life Processes
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18. Biotechnology
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19. Information Technology
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20. Space Technology
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National & International Current Affairs (CA) 2025
Current affairs of all months are given below
delete UPSC Sample Notes [English]

xxviii.1.  Evolution of Mobile Networks

About Evolution

  • Mobile phones communicate through ground-based cellular networks. Cellular networks are divided into ‘communication cells’ with which our mobile phones and mobile devices communicate.
  • Mobile communication involves transmitting voice or data using wireless radio transmission.
  • The first mobile systems were based on analogue transmission called as 1G. 
  • The second-generation mobile systems were based on digital transmission.
  • Initially only voice was carried over the network.
  • The commonly used standards for voice communication were GSM and CDMA.
  • These days, most mobile communications use Long Term Evolution communication– or LTE which allows us to communicate with voice and data simultaneously over the same network. 
  • The rules for carrying voice or data in a network are defined under the standards for mobile network communications often seen as 2G, 3G, 4G and 5G.

1G

  • Mobile phones began with 1G technology in the 1980s.
  • 1G is analog technology that supported only voice communications.
  • The maximum speed is 2.4 Kbps.

2G

  • First launched in 1991.
  • For the 1st time radio signals became digital rather than analog.
  • 2G phones are used for data also along with voice. 
  • Thus, 2G telephone introduced call and text encryption, SMS, picture messages, and MMS.
  • Maximum speed under 2G networks with General Packet Radio Service (GPRS) was 50 kilobits per second.
  • With Enhanced Data Rates for GSM Evolution (EDGE) the speed went up to 1mbps

GPRS

  • Launched in 2000
  • Bridge between 2G and 3G.
  • It marks the coming of data transmission besides voice communication.
  • General Packet Radio Service enabled mobile devices to send and receive e-mails and pictures.
  • GPRS used EDGE and GSM standards for both voice and data transmission.
  • GPRS had operating speeds of up to 115kbit/s.
  • It increased to a maximum of 384kbit/s by using EDGE.

3G

  • The introduction of 3G networks in 1998 ushered in faster data-transmission speeds.
  • Maximum speed of 3G is estimated to be around 2 Mbps for non-moving devices and 384 Kbps in moving vehicles. 
  • Further a 3G phone cannot communicate through a 4G network, but a 4G phone can communicate through a 3G or even 2G networks.
  • Under both 2G to 3G technologies, data and voice transmission over the different networks using GSM or CDMA technology.

4G

  • 4G uses LTE which allows us to communicate with voice and data simultaneously over the same network.
  • Applications include amended mobile web access, IP telephony, gaming services, high-definition mobile TV, video conferencing, 3D television, and cloud computing.
  • The max speed of a 4G network when the device is moving is 100 Mbps or 1 Gbps for low mobility communication like when stationary or walking.

 

1G

2G

3G

4G

Period

1980-1990

1990-2000

2000-2010

2010-(2020)

Bandwidth

150/900MH2

900MHz

100MHz

100MHz

Frequency

Analog signal  (30 Khz)

1.8GHz (digital)

1.6-2.0 GHz

2-8 GHz

Data rate

2kbps

64kbps

144kbps-2Mbps

100Mbps-lGbps

Characteristic

First wireless communication

Digital

Digital broadband, increased speed

High speed, all IP

Technology

Analog cellular

Digital cellular (GSM)

CDMA, UMTS, EDGE

LTE, WiFi