Broadcast bands vs. microwave range – Order of frequency comparison AM, PM (radio), and terrestrial TV broadcast bands fall in which range relative to the microwave frequency spectrum?

Introduction:
The term “microwave” typically refers to frequencies from about 1 GHz to 30 GHz (and sometimes extended to 300 GHz as millimeter waves). Classic broadcast bands for AM, FM/PM, and many TV channels occupy much lower frequencies, primarily in the kHz–MHz (AM) and MHz (FM/TV VHF/UHF) ranges.

Given Data / Assumptions:

• AM broadcast: roughly 530–1700 kHz.
• FM (often called PM/angle modulation in textbooks): around 88–108 MHz.
• TV terrestrial: VHF and UHF bands, mostly tens to hundreds of MHz (some UHF into hundreds of MHz).

Concept / Approach:

Comparing with microwaves (≥ 1 GHz), these broadcast services are at far lower frequencies. Even the higher UHF TV channels remain below 1 GHz in many allocations, still beneath the start of the microwave region. Therefore, their frequencies are much lower than the microwave range.

Step-by-Step Solution:

Verification / Alternative check:

Radio spectrum charts place broadcast services well below microwave allocations such as radar, Wi-Fi, and satellite links.

Why Other Options Are Wrong:

“Same order” and “much higher” contradict the numeric ranges; “either (a) or (c)” is logically inconsistent; “exactly equal” is false.

Common Pitfalls:

Confusing UHF TV near 1 GHz as “microwave”; conventional definitions place the microwave threshold at or above 1 GHz.

Final Answer:

much lower than microwave range.