A cellular system is a network architecture used in mobile communications, dividing a geographical area into smaller regions called cells to efficiently utilize frequency spectrum and provide seamless connectivity. Each cell is served by a base station (BS), which connects mobile users to the network.

Components of Cellular Systems:

  1. Mobile Station (MS):

    • The user's device (e.g., smartphone) that communicates with base stations.

    • Consists of a transceiver, antenna, and control circuitry.

  2. Base Station (BS):

    • Includes antennas, transmitters, and receivers to handle wireless communication.

    • Each BS is linked to the Mobile Switching Center (MSC).

  3. Mobile Switching Center (MSC):

    • Acts as the central hub managing calls and data sessions.

    • Handles call routing, handovers, authentication, and billing.

  4. Base Station Controller (BSC):

    • Manages multiple base stations.

    • Controls frequency allocation, handovers, and power management.

  5. Public Switched Telephone Network (PSTN):

    • Enables interconnection between cellular networks and traditional landlines.

  6. Home Location Register (HLR) & Visitor Location Register (VLR):

    • Stores subscriber information, including authentication and location details.



Working of Cellular System:

Each cell uses a specific set of frequencies, reducing interference and allowing frequency reuse in non-adjacent cells. When a user moves, the system hands over the connection between base stations without interruption.

Cellular systems have evolved from 1G (analog) to 5G (high-speed digital), offering increased capacity, efficiency, and data rates for modern communication.