Explore the essential concepts of cellular network architecture, including how cells are organized, the mechanisms of handoffs, and the challenges of roaming across networks. This quiz is designed to help you reinforce your understanding of coverage strategies, mobile connectivity, and seamless communication in cellular systems.
In a standard cellular network, what is the primary function of dividing coverage areas into multiple hexagonal cells?
Explanation: Dividing the coverage area into hexagonal cells allows frequency resources to be assigned efficiently to different locations, supporting more users and reducing interference. Increasing the number of antennas supports capacity but is not the main reason for using cells. Reducing signal strength is not desirable, as it limits coverage. Ensuring only one user is connected at a time contradicts the network's goal of supporting many simultaneous users.
When a mobile user moves from one cell to another during a call, which type of handoff involves a network-controlled process based on signal measurements from multiple base stations?
Explanation: A network-controlled handoff relies on the network to collect and analyze signal measurements from several base stations before deciding to transfer the call. Mobile-assisted handoff involves the mobile device sending its own measurements but not controlling the process. Hard-off is a misused term; the correct term is 'hard handoff,' which is a type, not a control scheme. Frequency hopping describes changing frequencies to avoid interference, not a handoff process.
Why do cellular systems typically design cells with a certain degree of overlap in their coverage areas?
Explanation: Cell overlap ensures that users moving between adjacent cells remain connected and experience uninterrupted service through handoffs. Reducing the number of cells is not an aim of overlap, as coverage still needs to be maintained. Eliminating the need for base stations is impossible; they are essential for coverage. Overlap does not prevent all interference; careful planning is needed to manage interference.
When a user travels to a location served by a different network provider, which main challenge must the cellular system address to enable successful roaming?
Explanation: Successful roaming requires networks to securely authenticate users and manage billing across different providers to enable service continuity. Simply increasing the frequency range may not solve compatibility issues alone. Eliminating all call drops is unrealistic though minimizing them is important. Forcing manual network selection is undesirable, as automatic roaming is a key feature for user convenience.
Which type of handoff, often called 'break-before-make,' disconnects from the old cell before connecting to the new cell?
Explanation: A hard handoff terminates the connection with the previous cell before establishing a new one, characteristic of 'break-before-make.' A soft handoff connects to the new cell before breaking the old connection—known as 'make-before-break.' Horizontal handoff refers to movement within the same technology, not the connection process. 'Soft-off' is not a recognized term in this context.