Understanding Second Generation (2G) Mobile Systems

The Second Generation (2G) of mobile communication technology marked a significant shift from the analog First Generation (1G) systems. 2G introduced digital voice encryption, improved capacity, and basic data services like SMS (Short Message Service). It primarily used digital signals instead of analog ones.

Key Technologies Introduced in 2G

Several key standards and systems were introduced or became prominent during the 2G era. These include:

• GSM (Global System for Mobile Communications): The most widely adopted 2G standard globally, particularly dominant in Europe and many other parts of the world. It introduced digital communication and SMS.
• PDC (Personal Digital Cellular): Primarily used in Japan, PDC was another digital 2G standard that competed with GSM and CDMA in its region.
• IS-54 (Digital AMPS or TDMA): This was an evolution of the earlier analog AMPS system in North America, making the transition to digital using Time Division Multiple Access (TDMA). It was later succeeded by IS-136.
• CDMA (Code Division Multiple Access): Standards like IS-95 emerged in the 2G era, offering a different approach to digital transmission using spread spectrum technology.

Identifying Technologies Not Introduced in 2G

The question asks which technology listed was not introduced as part of the Second Generation mobile system. Let's analyze the options:

• GSM is a quintessential 2G technology.
• PDC was a 2G system used in Japan.
• IS-54 was a significant 2G digital standard, especially in North America.
• IS-35 does not represent a core mobile system standard introduced in the 2G generation like GSM, PDC, or IS-54. While standards related to digital cellular performance (like those numbered in the IS series) existed, IS-35 is not typically categorized as a major 2G network system standard itself. It often relates to specific performance or testing requirements rather than the fundamental network architecture of 2G.

Therefore, IS-35 is the technology that was not introduced as a primary component or standard of the Second Generation mobile system compared to the others listed.