PART 88—UNMANNED AIRCRAFT CONTROL SERVICES
Partially Active Regulation FCCPart 88 of the FCC rules sets technical standards for UAS operations within the 5030 to 5091 MHz band, focusing on CNPC. It allocates 5040 to 5050 MHz for NNA users, who will receive frequency allocations via DFMS. Initially, NNA users access 5040-5060 MHz under the IAM process until DFMS management begins.
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Summary of Technical Regulations
| Technical Requirement | Description | Notes & Citations |
|---|---|---|
| Frequency Band | 5030 - 5091 MHz for
General UAS1 operations
|
See 47 CFR § 88.1 |
|
Designated NNA Spectrum
|
5040 - 5050 MHz (10 MHz) | NNA2 users may access the 5040-5060 MHz (20 MHz) band under the IAM process, as outlined in 47 CFR § 88.141, before the approval and commencement of operation by the first DFMS3 administrator |
|
Transmitter Power
|
Transmitters must comply with RTCA DO-362A § 2.2.1.6.1 and associated subsections. | See 47 CFR § 88.101 |
|
Emissions Bandwidth
|
Must comply with requirements in technical standard RTCA DO-362A §§ 2.2.1.5.2, 2.2.1.5.3, 2.2.1.5.4, and 2.2.1.5.6
|
See 47 CFR § 88.103 |
|
Emission Mask
|
Must comply with RTCA DO-362A § 2.2.1.6.2.1
|
See 47 CFR § 88.105 |
|
Time Division Duplex Requirement
|
Must comply with TDD specified in RTCA DO-362A § 2.2.1.3 and § 2.2.1.3.1
|
See 47 CFR § 88.109 |
- UAS (Uncrewed Aircraft Systems) - A UA and its associated elements (including an uncrewed aircraft station, communication links, and the components not on board the UA that control the UA).
- NNA (Non-Networked Access) - This refers to temporary, interference-protected access to the 5030-5091 MHz band and as per 47 CFR § 88.25, are limited to Control and Non-payload Communications (CNPC) links.
- DFMS (Dynamic Frequency Management Systems) - A frequency coordination system operating in the 5030-5091 MHz band that is automated and assign temporary protected use of certain frequencies for a particular geographic area and period tailored to the operator’s submitted operation, to the extent such frequencies are available.
47 CFR Part 88 outlines the technical requirements for unmanned aircraft communication services in the 5030-5091 MHz band, specifying standards for transmitter power, emission types, and frequency management to ensure reliable communication and prevent interference. Engineers and operators should consider the following technical details:
-
Transmitter Power Limits (47 CFR § 88.101):
Transmitters used for unmanned aircraft control must comply with power output limits to prevent interference. The rules specify maximum power levels based on the frequency band used and the type of communication system (e.g., non-networked or DFMS-based). High power mode ground transmitter < 10 Watts. -
Bandwidth and Emission Standards (47 CFR §§ 88.103, 88.105):
Part 88 sets limits on the bandwidth of emissions and defines acceptable types of emissions for unmanned aircraft communication. These standards help minimize interference with other users of the radio spectrum by ensuring that signals remain within designated frequency bands.
Before DFSM (Dynamic Frequency Management System) is operational - Non-Networked Access (NNA) entities can use 20 MHz 5040-5060 MHz; when DFSM is operational NNA operation limited to 10 MHz 5040-5050 MHz -
Performance Standards and Equipment Authorization (47 CFR §§ 88.107, 88.111):
Communication equipment used for unmanned aircraft must meet specific performance criteria for signal quality, reliability, and interference avoidance. Equipment must be authorized by the FCC, ensuring it complies with Part 88 technical requirements. -
Dynamic Frequency Management Systems (DFMS) Requirements (47 CFR §§ 88.135-88.137):
DFMS dynamically allocate frequencies for unmanned aircraft control, adjusting assignments based on real-time conditions to optimize spectrum use. DFMS Administrators coordinate frequency management to avoid conflicts, ensuring safe and reliable operation. -
Non-Networked Access Usage (47 CFR § 88.31):
Systems operating independently of centralized networks must follow specific operational guidelines, including frequency management practices to reduce interference risks. Operators must ensure their systems can adapt to changing frequency availability. -
RF Safety Guidelines (47 CFR § 88.113):
RF safety measures are required to protect users and the public from potential exposure risks. The rules establish exposure limits based on power levels and operating conditions for unmanned aircraft communication systems. -
Incorporation of Industry Standards (47 CFR § 88.115):
Part 88 incorporates recognized industry standards for equipment and communication practices, ensuring consistency and safety across different unmanned aircraft communication systems.
Contact us for engineering and technical support on unmanned aircraft communication, FCC Part 88 compliance, drone RF safety, transmitter power limits for UAVs, non-networked access technical requirements, and more.
Frequency Allocation in CBRS and the Role of the DFMS.
This article reviews FCC Part 88 frequency allocation for UAS, detailing the Dynamic Frequency Management System (DFMS) in the 5030-5091 MHz band.
UACS Frequency AllocationUAS Regulatory Milestones
With increased UAS applications in the U.S., the FCC is taking a phased approach to implementing the UAS part 88. The following chart shows the timelines it has taken for the part to be adopted in its current form:
