28.0 GHz Band
Understanding the 28.0 GHz Band
In 2018, the United States was desperate to win the "Race to 5G." They needed massive chunks of empty millimeter-wave spectrum. The global telecommunications community (the ITU) agreed that the 26.0 GHz band should be the universal standard.
However, the US military and satellite industries were already heavily using the 26 GHz band. The FCC pivoted and instead aggressively auctioned off the adjacent 28.0 GHz Band to Verizon and AT&T.
The 5G Ultra Wideband Physics
Operating at a physical wavelength of just 1.07 centimeters, 28 GHz violates every traditional rule of cellular engineering.
| The Limitation | The 28 GHz Reality |
|---|---|
| Zero Penetration | A 28 GHz wave will not penetrate a brick wall. It will not penetrate the Low-E energy-efficient glass of an office building. It struggles to pass through the leaves of a heavy oak tree. It is strictly a Line-of-Sight, outdoor technology. |
| Micro-Cell Density | A 28 GHz cell tower (node) can only cover a radius of roughly 500 to 1,000 feet. To cover a single city block, a carrier must bolt three separate, massive MIMO antennas to the streetlamps. |
| The Speed Reward | The sole reason carriers suffer the extreme physics is raw speed. Because the band is completely empty, Verizon can bond massive 100 MHz channels together to push 4 Gigabits per second directly to a smartphone standing on a street corner or sitting inside a massive NFL stadium. |
The Satellite Battle
The US decision to use 28 GHz for 5G caused a massive international headache.
In Europe and the rest of the world, 28 GHz is strictly reserved for the Ka-Band Satellite Uplink. Ground stations blast data up to satellites at exactly 28 GHz. The satellite industry warned that if thousands of 5G cell towers suddenly started blasting 28 GHz horizontally across American cities, the massive "noise floor" would bleed into the sky and permanently deafen the sensitive receivers orbiting 22,000 miles above the Earth. The FCC ultimately compromised, allowing both to share the band using complex, localized exclusion zones.
Key Equations
The 28.0 GHz Band (encompassing 27.5 to 28.35 GHz) is a highly contentious millimeter-wave (mmWave) frequency that served as the primary, foundational spectrum for the...
Key specifications:
28.0 GHz | 28.35 GHz | 400 MHz | 28 GHz | 26.0 GHz
Power: P(dBm) = 10log(PmW), 0dBm = 1mW
Comparison
| Band | Range | Wavelength | Application | Standard |
|---|---|---|---|---|
| 28.0 GHz Band | 28 GHz region | 10.7 mm | Primary use | ITU allocation |
| Adjacent lower | 25.2 GHz | 11.9 mm | Related band | Shared spectrum |
| Adjacent upper | 30.8 GHz | 9.7 mm | Related band | Guard band |
| Harmonic 2f | 56.0 GHz | 5.4 mm | Spurious | Filter required |
| Sub-harmonic | 14.0 GHz | 21.4 mm | LO option | Mixer design |
Frequently Asked Questions
Does 28 GHz drain my phone battery?
Yes. To capture a fragile 28 GHz wave, your smartphone uses a highly advanced, microscopic 'phased array' antenna hidden in the edge of the glass. When the phone connects to a mmWave tower, it must actively power this array to electronically steer its receiving beam toward the tower, burning significantly more battery power than a standard sub-6 GHz 5G connection.
Can 28 GHz be used for home internet?
Yes, it is called Fixed Wireless Access (FWA). A technician mounts a small 28 GHz receiver directly to the outside of your house, pointing it with mathematical precision at the cell tower down the street. Because it sits outside, it bypasses the window penetration problem, bringing multi-gigabit speeds into the home without digging a trench for a fiber-optic cable.
Are other countries using 28 GHz for 5G?
Very few. The vast majority of the world (Europe, China, Australia) standardized on the '26 GHz Pioneer Band' (Band n258). The US, South Korea, and Japan were the primary outliers adopting the 28 GHz band (Band n261), creating a headache for smartphone manufacturers like Apple, who must build multiple different mmWave antennas into the iPhone.