communication

Communication is the process by which information is encoded by a sender, transmitted through a medium or channel, and decoded by a receiver, with feedback closing the loop. The canonical engineering model is the Shannon–Weaver model (Claude Shannon and Warren Weaver, A Mathematical Theory of Communication, 1948), which introduced the concepts of source, transmitter, channel, noise, receiver and destination, and quantified information in bits. In administrative and governance contexts, communication denotes both the constitutional channels of information flow — between citizen and state, and between organs of government — and the physical infrastructure (telecommunications, postal services, broadcasting, internet) that carries it. For exam purposes the term spans two registers: the science-and-technology register (how signals propagate) and the public-administration register (how organisations and governments exchange information).

Technically, communication systems are classified by channel into wired (copper, coaxial, optical fibre) and wireless (radio, microwave, satellite). Modern systems are predominantly digital, relying on modulation (AM, FM, PSK, QAM), multiplexing (FDMA, TDMA, CDMA, OFDMA), and packet switching governed by protocols such as TCP/IP. Mobile telephony has evolved through generations — 1G analog, 2G GSM/CDMA, 3G, 4G LTE, and 5G NR (3GPP Release 15 onward, 2019), with 6G under research targeting terahertz bands. Satellite communication uses GEO, MEO and LEO constellations; India's INSAT and GSAT series, operated by ISRO, provide telecommunication, broadcasting and meteorological links. Optical fibre, exploiting total internal reflection, carries terabits per second and forms the backbone of submarine cables and projects such as BharatNet, which aims to connect India's gram panchayats. In organisational theory, communication is classified as formal/informal, vertical/horizontal/diagonal, and verbal/non-verbal, with barriers (semantic, psychological, organisational) studied under public administration.

In governance, communication is constitutionally significant: Article 19(1)(a) of the Indian Constitution protects freedom of speech and expression, which the Supreme Court in Secretary, Ministry of Information and Broadcasting v. Cricket Association of Bengal (1995) extended to the right to receive and impart information over airwaves, holding that the electromagnetic spectrum is public property. The Telecom Regulatory Authority of India (TRAI), established by statute in 1997, and the Telecommunications Act, 2023 (replacing the Indian Telegraph Act, 1885) regulate the sector. Globally, the International Telecommunication Union (ITU), a UN specialised agency founded in 1865, allocates spectrum and orbital slots. Digital communication policy intersects with data protection (Digital Personal Data Protection Act, 2023) and net neutrality, which TRAI affirmed in 2018.

For the exam, communication is tested across multiple papers. In the UPSC General Studies Paper III science-and-technology section, candidates face questions on 5G, satellite communications, optical fibre, and spectrum auctions. In public administration optional and ethics papers, the organisational communication models, barriers and the sender-receiver framework recur. International relations papers probe the ITU, global digital governance and undersea cable geopolitics. The typical question angle asks candidates to link a technology (e.g. 5G or LEO satellites like Starlink and OneWeb) to its developmental, security or regulatory implications, or to evaluate freedom-of-expression jurisprudence in the digital age — demanding both technical literacy and constitutional grounding.