Band 3 (1800 MHz)
Understanding Band 3
Band 3 owes its dominance to the GSM legacy. In the 1990s, nearly every country allocated 1800 MHz for GSM, creating a globally harmonized band with existing infrastructure (towers, antennas, fiber backhaul) on every continent. When LTE arrived, operators could refarm these sites by simply replacing the radio equipment while reusing the physical infrastructure, dramatically reducing the cost of 4G deployment compared to building on new spectrum.
The 75 MHz paired allocation supports three to four operators with 15 to 20 MHz each, enough for a primary LTE capacity carrier. At 1.8 GHz, propagation provides 1 to 3 km cell radius in urban environments with moderate building penetration. Band 3 is typically combined with a low-band coverage layer (Band 20 in Europe, Band 28 in Asia-Pacific) and a high-capacity layer (Band 7 at 2600 MHz or C-band) using carrier aggregation to provide both wide coverage and high throughput.
Band 3 Technical Parameters
UL: 1710 – 1785 MHz (75 MHz)
DL: 1805 – 1880 MHz (75 MHz)
Duplex spacing: 95 MHz
Path Loss Comparison (urban macro):
Band 3 (1800 MHz): PL = 127.0 + 37.6 log(dkm) dB
Band 1 (2100 MHz): PL = 128.4 + 37.6 log(dkm) dB
Band 7 (2600 MHz): PL = 130.2 + 37.6 log(dkm) dB
Band 3 advantage: 1.4 dB vs B1, 3.2 dB vs B7
LTE Capacity (20 MHz, 4×4 MIMO):
Peak DL: ~100 Mbps | Typical urban: 30–50 Mbps
Mid-Band LTE Comparison
| Band | Frequency | Paired BW | Operators Worldwide | Coverage |
|---|---|---|---|---|
| Band 3 (1800 MHz) | 1710-1880 MHz | 75 MHz | 700+ | Most deployed globally |
| Band 1 (2100 MHz) | 1920-2170 MHz | 60 MHz | 500+ | Primary 3G, LTE capacity |
| Band 7 (2600 MHz) | 2500-2690 MHz | 70 MHz | 400+ | Urban capacity layer |
| AWS (Band 4/66) | 1710-2200 MHz | 70 MHz | US/Canada primary | US mid-band |
Frequently Asked Questions
Why is Band 3 the most deployed LTE band globally?
Universal allocation (every country has 1800 MHz), large bandwidth (75 MHz paired), and existing GSM 1800 infrastructure that can be refarmed to LTE by replacing equipment while reusing towers and antennas. The GSMA prioritized Band 3 for LTE in 2011, and every chipset supports it. Over 700 operators in 200+ countries have deployed Band 3 LTE.
How does Band 3 compare to other mid-band allocations?
Slightly better coverage than Band 1 (1.4 dB lower path loss) and significantly better than Band 7 (3.2 dB advantage). 75 MHz total is the largest sub-3 GHz FDD allocation. At 1.8 GHz, urban cell radius is 1 to 3 km with moderate building penetration. Band 3 is the mid-band sweet spot for coverage and capacity balance.
What is the refarming process from GSM to LTE on Band 3?
GSM traffic is migrated to GSM 900 or VoLTE, freeing 1800 MHz carriers (200 kHz each). Freed spectrum is aggregated into wider LTE carriers (5 to 20 MHz). The process takes 3 to 5 years per operator. Physical infrastructure (towers, antennas, power, fiber) is reused; only radio equipment changes, making Band 3 LTE deployment significantly cheaper than greenfield spectrum.