Consider the following statements : Cellular technology evolves in stages called Generation (G), where 1. A Generation represents the number of subscribers; higher Generation has more subscribers. 2. 2G technology has two standards CDMA and GSM. 3. 2G technology has CDMA standard and 3G has GSM standard. Which of the above statements is/are correct ?
- (a)1 and 3 only
- (b)1 only
- (c)3 only
- (d)2 only
Answer
Why
Correct — D, (d) 2 only.
START BY FIXING WHAT A GENERATION IS, because statement 1 offers a definition and the whole item turns on it. In mobile telephony a GENERATION is a family of standards defined by the RADIO TECHNOLOGY it uses and the SERVICES it can deliver. Each generation is a technical break with the one before it, not a bigger version of it:
1G — analogue, voice only. 2G — digital voice, plus text messaging and very slow data. This is where GSM and CDMA belong. 3G — data-capable networks that made the mobile internet, video calling and mobile broadband practical. 4G — an all-internet-protocol network, high-speed broadband, with voice itself carried as data. 5G — much higher speeds and much lower delay, designed also for very large numbers of connected machines.
STATEMENT 1 — 'A Generation represents the number of subscribers; higher Generation has more subscribers.' INCORRECT. The number is a technology label, not a headcount. Nothing about the definition refers to how many people use a network, and subscriber numbers move in the opposite direction at the start of every generation: on the day a new generation is switched on it has almost no subscribers at all, while the older one carries the entire country. What is true is that a newer generation eventually gains users as handsets and coverage spread, but that is a fact about adoption, not the meaning of the word.
STATEMENT 2 — '2G technology has two standards CDMA and GSM.' CORRECT, and it is the one statement that survives. Second-generation mobile telephony grew into two rival digital families. GSM, developed in Europe and standardised by the European Telecommunications Standards Institute, divides each radio channel by TIME so several calls share it in turn, and gave the world the removable SIM card. CDMA, in its second-generation form, spreads every call across a wide band and separates the calls by giving each a distinct CODE. Both were deployed in India and the two names were the ordinary vocabulary of the mobile market when this paper was set.
STATEMENT 3 — '2G technology has CDMA standard and 3G has GSM standard.' INCORRECT, and it is a straightforward reversal of the facts. GSM is a SECOND-generation standard, not a third-generation one, and CDMA is second-generation too — the two are contemporaries, not successors. Each family then had its OWN third-generation successor: the GSM line moved through packet-data upgrades to UMTS, and the CDMA line to CDMA2000. The confusion the statement trades on is real and worth naming: the third-generation successor of the GSM family uses wideband code division multiple access as its radio technique, so the letters CDMA appear in 3G as well — but as a method of sharing the radio spectrum, not as the name of the older 2G standard.
So statement 2 alone is correct, which is option (d).
TWO THINGS ABOUT THE PRINTING WORTH NOTICING. The item prints an extra line of its own — 'Cellular technology evolves in stages called Generation (G), where' — between the 'Consider the following statements' line and the numbered list, and the question sentence follows the list with no separate line of codes. And the four options are NOT in ascending order: they run 1 and 3 only, 1 only, 3 only, 2 only. An option set out of sequence has to be read item by item, because the position of a choice on the page carries no information at all.
Why the others are wrong
- (a)1 and 3 only — Accepts both of the false statements and rejects the only true one, so it is the exact inverse of the position the facts support. Statement 1 fails because a generation is defined by technology and capability, never by subscriber numbers — a new generation begins with essentially no subscribers, which is the reverse of what the statement asserts. Statement 3 fails because it places GSM in the third generation, where it does not belong: GSM and CDMA were both SECOND-generation families, running side by side through the 1990s and 2000s, and each had its own third-generation successor. Marking this option usually follows from reading the statements as a story of progress — an older technology replaced by a newer one — instead of as two parallel families, each of which evolved on its own track.
- (b)1 only — Takes the definition in statement 1 at face value and rejects the one statement that is accurate. The definition is the error: a generation of mobile telephony is a set of technical standards — what the radio interface does and what services it can carry — and the numbering marks successive technical breaks, from analogue voice, to digital voice and messaging, to mobile data, to an all-internet-protocol network. Subscribers are counted separately and by other people. It is worth noticing that the statement smuggles in a second claim after the semicolon: 'higher Generation has more subscribers'. Even read as a claim about adoption rather than about definition, that is not reliably true at any given moment, because the newer generation is always the smaller one until migration is complete. A statement that asserts a definition AND a consequence has to satisfy both, and this one satisfies neither.
- (c)3 only — Accepts the reversal and rejects the fact. Statement 3 asserts that CDMA is the 2G standard and GSM the 3G standard, which gets the relationship between the two families wrong in a way worth being precise about. GSM and CDMA are BOTH second-generation digital standards and were rivals in the same market at the same time; neither succeeded the other. The GSM family's own upgrade path ran through packet-data additions to a third-generation standard, and the CDMA family's ran to CDMA2000. Meanwhile statement 2, which this option rejects, states exactly the fact that statement 3 mangles: that the second generation had these two standards. Where two statements in the same set describe the same territory, one carefully and one carelessly, they are usually placed there to be compared — and the careful one is the one to test first.
Concept
THE GENERATIONS OF MOBILE TELEPHONY are successive families of standards, each defined by its radio technology and by what services it can carry.
1G — analogue radio, voice only, no security worth the name, from about 1980. 2G — digital. Voice is encoded into bits, which allows encryption, better spectrum use, and text messaging. Two families: GSM and CDMA. 2.5G and 2.75G — packet data added to existing 2G networks, known as GPRS and then EDGE, giving the first usable mobile internet. 3G — networks designed for data as well as voice: video calling, mobile broadband, and much higher data rates. UMTS on the GSM path, CDMA2000 on the other. 4G — an all-internet-protocol network built on LTE, with voice carried over the data network itself; broadband speeds on a handset. 5G — far higher speeds, much lower delay, and support for very large numbers of connected devices, aimed at industrial and machine-to-machine use as much as at people.
HOW USERS SHARE THE RADIO SPECTRUM is the technical distinction underneath all of this, and it explains the names:
FDMA — each call gets its own FREQUENCY band. The analogue method. TDMA — several calls share a frequency by taking turns in TIME slots. Central to GSM. CDMA — all calls occupy the same wide band simultaneously and are separated by a unique CODE given to each. OFDMA — the band is divided into many narrow sub-carriers allocated flexibly. The method of 4G and 5G.
GSM AND CDMA, THE TWO SECOND-GENERATION FAMILIES. GSM was standardised in Europe by the European Telecommunications Standards Institute and became the world's most widely deployed mobile standard; it introduced the removable SIM card, which is why a GSM subscriber could change handsets by moving a card. Second-generation CDMA, in its IS-95 form, came from the United States and used spread-spectrum radio; handsets were typically tied to the operator. Both were licensed and deployed in India, and the distinction between a GSM connection and a CDMA connection was familiar to every consumer in the years before this paper.
WHY THE LETTERS CDMA APPEAR TWICE. CDMA is both the name of a 2G standard family and the name of a general radio technique. The third-generation successor of GSM uses a wideband form of that technique. So a sentence containing 'CDMA' has to be read for which of the two it means, and mixing them up is exactly what statement 3 of this question is built on.
IN INDIA, mobile telephony is regulated by the Telecom Regulatory Authority of India, and spectrum for each generation has been assigned through auctions.
Computers, networks and information technology account for about eleven questions on this APFC paper, and telecommunications is a recurring corner of it because the sector is both a consumer subject and a policy subject. This item is asked entirely at the level of an informed newspaper reader: no engineering is required, only the knowledge that generation numbers describe technology.
The statement set is built the way this paper builds most of them. One statement offers a wrong DEFINITION, one states a plain fact, and one REVERSES a relationship between two real things. Those three shapes cover most of what a statement-analysis item can do, and each has its own defence. Against a definition, ask what the term actually means and whether the statement's version would survive an obvious test — here, that a new generation starts with no subscribers. Against a reversal, place the two things on a timeline and check which came first. Against a plain fact, simply confirm it.
The habit worth building is to judge every statement before looking at the options, and to write the verdicts down. On this item the options are printed OUT of ascending order, which punishes anyone reading them by shape rather than by content; a candidate who has already decided that only statement 2 stands will find its option wherever it happens to be, while one who scans the list for a familiar pattern will not.
The wider lesson from statement 1 is one this paper returns to: a label is not a measurement. The number in '4G' is a technology marker in the same way that a version number is, and reading it as a quantity — of users, of speed, of towers — is a mistake of the same family as reading a scheme's name as a description of its coverage.
Key facts
- A mobile GENERATION is a family of standards defined by radio technology and by the services it supports; it has nothing to do with the number of subscribers.
- 1G was analogue voice; 2G digital voice with text messaging; 3G mobile data and video; 4G an all-internet-protocol broadband network; 5G very high speed, very low delay and massive machine connectivity.
- The second generation had two major standard families: GSM, standardised in Europe, and CDMA in its IS-95 form.
- GSM shares a radio channel by dividing it into TIME slots and introduced the removable SIM card; 2G CDMA spreads calls across a wide band and separates them by unique CODES.
- GPRS and EDGE were packet-data upgrades to 2G networks, usually described as 2.5G and 2.75G.
- GSM is NOT a third-generation standard. The GSM family's 3G successor was UMTS, and the CDMA family's was CDMA2000.
- The 3G successor of the GSM family uses wideband code division multiple access as a radio technique, which is why the letters CDMA recur in 3G and cause confusion.
- The four ways of sharing spectrum are FDMA by frequency, TDMA by time, CDMA by code and OFDMA by flexible sub-carriers; 4G and 5G use the last of these.
- Both GSM and CDMA services were licensed and operating in India, and mobile telephony is regulated by the Telecom Regulatory Authority of India.
Study next
Common traps
- Reading a generation number as a quantity — of users, speed or coverage. It is a technology label.
- Believing a newer generation always has more subscribers. Every generation starts with almost none.
- Treating GSM and CDMA as belonging to different generations. Both are second-generation families and were contemporaries.
- Confusing CDMA the 2G standard with code division multiple access the radio technique, which is also used in 3G.
- Assuming a numbered option list runs in ascending order. On this item it does not, and the position of a choice carries no information.
- Accepting a statement that pairs a definition with a consequence after a semicolon without testing both halves.
Telecommunications on EPFO papers is asked as general awareness rather than engineering: what a generation of mobile technology means, what an abbreviation stands for, which body regulates the sector, what a stated policy target is. The commonest format on this particular paper is the numbered statement list, and the statements are built from three reliable shapes — a wrong definition, a plain fact and a reversed relationship. Judging each on its own and only then looking for the matching option is both faster and safer than trying to eliminate options directly, particularly where the option list is not printed in ascending order. Technology items also tend to reward knowing the Indian side of the story — the regulator, the policy, the auctions — because that is where a general ability paper connects the subject to administration.
Related PYQs
EPFO_APFC_2016_Q79Consider the following statements on Global Positioning System (GPS) : 1. GPS allows accurate time-stamping on ATM transactions. 2. GPS relies on a set of satellites for transferring signals worldwide. Which of the above statements is/are correct ?
- (a) 1 only
- (b) 2 only
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer(c) Both 1 and 2
Two statements on the Global Positioning System, printed immediately before this item — the same statement-analysis format applied to the neighbouring satellite technology.
EPFO_APFC_2016_Q25Which of the following are incorporated in the Government approved National Telecom Policy, 2012 ? 1. Broadband for all with a minimum download speed of two megabits per second 2. India's rural tele-density to be improved from 39% to 70% in the next five years 3. Roaming charges shall be scrapped Select the correct answer using the codes given below :
- (a) 1 and 2 only
- (b) 1 and 3 only
- (c) 2 and 3 only
- (d) 1, 2 and 3
Answer(d) 1, 2 and 3
What the National Telecom Policy, 2012 incorporates, including a minimum broadband download speed — the policy side of the same telecommunications strand.
EPFO_APFC_2016_Q81LAN, WAN and MAN are computer networks covering different areas. Their first alphabets L, W and M respectively stand for
- (a) Local, World and Middle
- (b) Long, Wireless and Metropolitan
- (c) Local, Wide and Metropolitan
- (d) Least, Wireless and Maximum
Answer(c) Local, Wide and Metropolitan
What the L, W and M of LAN, WAN and MAN stand for — networking vocabulary on the same paper, tested as an expansion rather than as statements.
Practice
- practice — not a real PYQ
In mobile telephony, GSM stands for
- (a)General Switching for Mobiles
- (b)Global System for Mobile Communications
- (c)Grouped Signal Modulation
- (d)Global Standard for Messaging
Answer(b) Global System for Mobile Communications — standardised in Europe and the most widely deployed second-generation mobile standard, and the family that introduced the removable SIM card.
- practice — not a real PYQ
GPRS and EDGE, which added packet data services to existing second-generation mobile networks, are usually described as
- (a)1G technologies
- (b)2·5G and 2·75G technologies
- (c)3G technologies
- (d)4G technologies
Answer(b) 2·5G and 2·75G technologies — both were upgrades layered on 2G networks to carry packet data, falling between the second and third generations rather than constituting a generation of their own.