Spectrum
The range of electromagnetic radio frequencies used for wireless communication, allocated by regulatory bodies such as the ITU and national agencies.
Spectrum is the raw material of every wireless network, and unlike most raw materials there is a fixed amount of it. That scarcity is why it gets carved up so carefully: the ITU sets the global framework, then national regulators (the FCC, Ofcom, etc.) auction or license specific bands to operators, often for billions.
Where a band sits matters as much as how much you hold. Low bands (around 600–900 MHz) travel far and go through walls, which is why they carry rural coverage and indoor signal. Mid-band (the 3.5 GHz range) is the workhorse for 5G capacity. The millimetre-wave bands up at 24 GHz and above offer huge chunks of spectrum but barely reach a city block. An operator's band portfolio basically dictates what kind of network it can build.
Frequently asked questions
- Why is low-band spectrum so valuable if it carries less data?
- Because coverage is expensive. A low-band signal propagates much further and penetrates buildings far better than mid- or high-band, so one low-band site covers an area that would need many mid-band sites. For rural footprint and reliable indoor service it is hard to beat, which keeps demand (and auction prices) high even though the per-site capacity is modest.
Related terms
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