Multiplexing principle: Radio broadcasting with multiple stations in the same area is primarily an example of which multiplexing technique?

Introduction / Context:
Broadcast radio assigns different stations to different carrier frequencies so that many programs can be transmitted simultaneously without mutual interference, provided receivers are tuned to one carrier at a time.

Given Data / Assumptions:

• Conventional AM/FM analog broadcasting scenario.
• Single antenna may radiate one station per frequency; many stations share the spectrum.
• Receivers select one station by tuning to its frequency.

Concept / Approach:

This is classic Frequency Division Multiplexing (FDM): separate information channels occupy distinct, non-overlapping frequency bands simultaneously. Time or code division are not used in legacy analog broadcast systems.

Step-by-Step Solution:

Verification / Alternative check:

Broadcast band plans assign channel center frequencies and bandwidths; receivers use selective IF filtering to extract the chosen station.

Why Other Options Are Wrong:

• Time multiplexing: would interleave in time (not typical in analog broadcasting).
• Space multiplexing: relies on spatial separation/antennas; not the core method here.
• Code multiplexing: associated with CDMA-type systems, not analog broadcast radio.

Common Pitfalls:

• Confusing modern digital broadcast multiplexes (e.g., OFDM subcarriers) with analog radio channelization; the principle remains frequency separation.

Final Answer:

Frequency multiplexing