The Citizens Broadband Radio Service (CBRS) in the 3.5 GHz band (Band 48) has become the dominant spectrum choice for private LTE and 5G deployments in the United States. If you're running a private network on a different band — or if your existing CBRS deployment needs a platform upgrade — migrating to (or within) CBRS involves specific considerations around spectrum access, SAS coordination, and device compatibility.
This guide covers what you need to know.
CBRS Spectrum Basics
CBRS operates in the 3550–3700 MHz range and uses a three-tier spectrum sharing framework managed by a Spectrum Access System (SAS):
- Incumbent Access (Tier 1): Federal users (primarily Navy radar) and grandfathered satellite operators. They have top priority and can preempt all other users.
- Priority Access License (PAL — Tier 2): Licensed spectrum purchased at auction, organized by county. PAL holders get interference protection from GAA users but must yield to incumbents.
- General Authorized Access (GAA — Tier 3): Shared, unlicensed-like access available to anyone with a certified CBRS device. No license fee, but no interference protection from PAL or incumbent users.
Most private network deployments use GAA access — it's free, immediately available, and sufficient for indoor and campus environments where interference is manageable. PAL licenses are valuable for outdoor, mission-critical, or high-density deployments where guaranteed spectrum access matters.
What Changes During a CBRS Migration
If you're migrating from a non-CBRS band (e.g., Band 41, Band 14, or licensed spectrum) to CBRS Band 48, several things change:
- SAS registration: Every CBSD (Citizens Broadband Radio Service Device — your eNodeB or gNodeB) must be registered with a SAS provider. The SAS dynamically manages your frequency assignment, power levels, and grants based on incumbent activity and other users in the area.
- Device certification: Only FCC-certified CBRS devices (both infrastructure and end-user) can operate in Band 48. Your existing radios may not be CBRS-certified, which means hardware replacement.
- Power limits: CBRS has specific EIRP limits — 30 dBm/10 MHz for Category A (indoor) devices, 47 dBm/10 MHz for Category B (outdoor) devices. This affects your RF planning and coverage footprint.
- Dynamic frequency assignment: Unlike fixed-frequency licensed bands, CBRS grants can change. Your core and RAN must handle grant updates, channel reassignment, and potential suspension events from the SAS.
- End-device compatibility: Not all LTE/5G devices support Band 48. Scanners, tablets, routers, and CPE must be verified for CBRS support — or replaced.
Migrating Within CBRS (Platform Upgrade)
If you're already on CBRS but migrating from one platform to another (e.g., from Baicells to BATS ECHO), the spectrum piece is simpler — you're staying on Band 48. The migration primarily involves:
- SAS re-registration: New CBSDs must be registered under your CPI (Certified Professional Installer) credentials. Old registrations are decommissioned.
- Core switchover: Your EPC/5GC migrates to BATS ECHO with subscriber databases, policies, and QoS profiles carried over.
- SIM reprovisioning: SIM profiles are updated to authenticate against the new core. Existing CBRS-capable devices typically don't need hardware changes.
- RF reoptimization: New radios may have different antenna patterns, power characteristics, or sector configurations. A fresh RF plan ensures you're getting optimal coverage.
CPI Requirements
Category B (outdoor) CBRS devices must be installed by a CPI — a Certified Professional Installer who is responsible for accurate location reporting, antenna parameters, and SAS registration. BATS Wireless maintains CPI certification and handles all SAS coordination as part of the migration.
Category A (indoor) devices have relaxed installation requirements but still need SAS registration.
RF Planning for CBRS
CBRS at 3.5 GHz behaves differently from lower bands like Band 41 (2.5 GHz) or Band 14 (FirstNet, 700 MHz). Key considerations:
- Propagation: 3.5 GHz has higher path loss than lower bands. Indoor penetration is moderate, and outdoor range is shorter. Plan for more sectors or higher antenna placement.
- Capacity: Up to 150 MHz of spectrum is available (depending on GAA/PAL allocation), which means high-capacity deployments are achievable with proper channel planning.
- Interference: In dense urban or industrial areas, other GAA users may be present. SAS coordination helps, but your RF design should account for shared spectrum conditions.
- Antenna selection: Sectorized antennas are typically preferred for outdoor deployments to maximize gain and control interference. Omni antennas work for small indoor cells.
How BATS Wireless Handles CBRS Migration
We manage the full CBRS migration process:
- Verify end-device Band 48 compatibility across your fleet
- Design RF plan optimized for 3.5 GHz propagation at your site
- Deploy BATS ECHO core and CBRS-certified radios
- Register all CBSDs with SAS under CPI credentials
- Reprovision SIMs and reconfigure devices
- Validate coverage, capacity, and SAS grant behavior
- Decommission legacy SAS registrations and hardware
Whether you're moving to CBRS for the first time or upgrading your existing CBRS platform, we handle the spectrum coordination so you can focus on operations.