Overview
CDMA frequency bands refer to the specific radio frequency ranges allocated for cellular networks that employ Code Division Multiple Access (CDMA) technologies. These bands are designated by national and international regulatory bodies to support various generations of CDMA standards, including IS‑95 (CDMAOne) and CDMA2000 (1xRTT, EV‑DO, and later 3GPP2 releases). Allocation of these bands varies by region and is coordinated to minimize interference with other services.
Standardized Bands
| Band Designation | Frequency Range (MHz) | Primary Use | Typical Standard(s) | Regional Deployment |
|---|---|---|---|---|
| Band 0 (Cellular) | 824–849 (uplink), 869–894 (downlink) | 2G/3G CDMAOne, CDMA2000 1xRTT | IS‑95, CDMA2000 1x | North America, parts of South America |
| Band 1 (PCS) | 1850–1910 (uplink), 1930–1990 (downlink) | 2G/3G CDMAOne, CDMA2000 1x, EV‑DO | IS‑95, CDMA2000 | North America, Caribbean |
| Band 2 (GSM‑850/1900) | 824–849 / 1850–1910 (uplink), 869–894 / 1930–1990 (downlink) | Dual‑mode (CDMA/GSM) devices | CDMA2000, GSM | Used in multi‑mode phones in the U.S. |
| Band 3 (450 MHz) | 450–470 (uplink), 470–490 (downlink) | Rural/low‑density deployments | CDMA2000 | Parts of Europe, Asia, Africa |
| Band 4 (AWS) | 1710–1755 (uplink), 2110–2155 (downlink) | 4G LTE migration, limited CDMA | CDMA2000 in early LTE‑Advanced trials | Some Asian markets |
| Band 5 (850 MHz) | 824–849 (uplink), 869–894 (downlink) | CDMA2000, LTE (re‑use) | CDMA2000 1x, EV‑DO | Worldwide, especially in developing regions |
| Band 6 (900 MHz) | 880–915 (uplink), 925–960 (downlink) | CDMA2000 in certain countries | CDMA2000 1x, EV‑DO | Europe, Middle East |
| Band 7 (1800 MHz) | 1710–1785 (uplink), 1805–1880 (downlink) | Primarily LTE, occasional CDMA pilots | Limited CDMA | Limited use |
| Band 8 (1900 MHz) | 1850–1910 (uplink), 1930–1990 (downlink) | CDMA2000, LTE | CDMA2000 1x, EV‑DO | North America, Latin America |
| Band 9 (850 MHz supplemental) | 832–862 (uplink), 851–881 (downlink) | Supplemental CDMA carrier | CDMA2000 | United States (e.g., Sprint) |
| Band 10 (1700 MHz) | 1710–1750 (uplink), 2110–2150 (downlink) | CDMA in early 4G transition | CDMA2000 (rare) | Limited experimental use |
Note: The band numbers above follow the convention used by the International Telecommunication Union (ITU) and the United States Federal Communications Commission (FCC) for mobile services. Some regions may reference the same frequencies by different band identifiers.
Regulatory Context
- United States: The FCC allocates the 824–849 MHz and 869–894 MHz pairs (Band 0) for cellular CDMA services, while the 1850–1910 MHz and 1930–1990 MHz pairs (Band 1) are assigned to PCS. Additional spectrum, such as 850 MHz (Band 5) and 1900 MHz (Band 8), is shared among CDMA, GSM, and LTE operators under flexible licensing.
- Europe and Asia: National regulators typically assign the 450 MHz (Band 3) and 900 MHz (Band 6) ranges for CDMA2000, especially for rural coverage and legacy networks.
- International Coordination: The ITU’s Radio Regulations (RR) provide global coordination to prevent cross‑border interference, defining the primary and secondary status of CDMA allocations within each allocation table (e.g., Table 1 for the 824–849 MHz range).
Technical Characteristics
- Channel Bandwidth: CDMA channels are generally 1.25 MHz wide, though 5 MHz carrier aggregation is used in later CDMA2000 releases and in LTE‑Advanced fallback scenarios.
- Duplex Mode: Most CDMA frequency bands employ Frequency Division Duplex (FDD), separating uplink and downlink bands by 45 MHz (e.g., 824–849 MHz uplink paired with 869–894 MHz downlink).
- Power Levels: Regulatory limits for Mobile Station (MS) transmit power vary by band, commonly 23 dBm for handheld devices in the 800–900 MHz ranges and 20 dBm for higher bands.
Evolution and Legacy
CDMA frequency bands were foundational for 2G and early 3G mobile services, particularly in the United States and parts of Asia. With the global shift toward LTE and 5G, many operators have repurposed CDMA bands for newer technologies through spectrum refarming. Nonetheless, the frequency allocations remain documented in national tables, and some legacy CDMA networks continue to operate, primarily to support machine‑to‑machine (M2M) and narrowband IoT services that benefit from the propagation characteristics of lower bands (e.g., 450 MHz and 800 MHz).
References
- Federal Communications Commission (FCC), Spectrum Management and Allocation Tables (2023).
- International Telecommunication Union (ITU), Radio Regulations, Section 5.1 (2022).
- 3GPP2, CDMA2000 Specification Suite (Release 6–10).
The information presented reflects the consensus of publicly available standards and regulatory documents up to 2024.