The maximum rate at which information can be transmitted reliably through a communication channel primarily depends on which parameter?

Introduction / Context:
Shannon’s communication theory defines limits for information transfer. While many factors affect link quality, the fundamental determinant of capacity is the channel bandwidth and the signal-to-noise ratio (SNR). This question highlights the role of bandwidth.

Given Data / Assumptions:

• Channel capacity formula: C = B * log2(1 + S/N).
• B = channel bandwidth.
• S/N = signal-to-noise ratio.

Concept / Approach:

For fixed SNR, increasing bandwidth linearly increases the number of bits per second that can be carried. Carrier frequency does not directly dictate capacity; losses and power affect SNR but not the structural limit. Bandwidth is the key parameter determining potential data rate.

Step-by-Step Solution:

Verification / Alternative check:

Modern high-data-rate systems (optical, Wi-Fi, 5G) exploit very wide bandwidth allocations, confirming this principle.

Why Other Options Are Wrong:

• Carrier frequency: only indirectly affects propagation, not capacity formula.
• Transmission loss: affects received SNR but not the fundamental dependency.
• Transmitted power: influences SNR but not as directly as bandwidth for maximum rate.
• Antenna gain: improves link margin, not fundamental capacity scaling.

Common Pitfalls:

Confusing carrier frequency allocation with actual usable bandwidth.

Final Answer:

Available channel bandwidth