4.3.18.20. Spectrum Management
4.3.18.20. Spectrum Management
Warfighters use spectrum-dependent systems for communications, sensors (i.e., radar), navigation beacons, jammers, homing devices, anti-Improvised Explosive Devices (IED), and other purposes. Often emitters are in close physical proximity to each other and to civilian devices that should not be disrupted by military signals. Spectrum-dependent system developers should be aware of the enemy electronic order of battle and countermeasures, and plan accordingly. Devices (including commercial items) that do not account for countermeasures may have vulnerabilities in hostile environments.
Spectrum management requirements are needed for all spectrum-dependent systems. Any system that uses an antenna or a platform that mounts such systems is a spectrum-dependent system. If a platform obtains a spectrum-dependent system as Government-furnished equipment (GFE), the platform Program Manager is responsible for ensuring that the GFE Program Manager has obtained the needed permissions. Both programs are required to submit a Spectrum Supportability Risk Assessment (SSRA). The platform SSRA can reference the GFE SSRA, but may have to expand upon it regarding host nation features or other information not contained in the GFE-level SSRA. The Systems Engineer should be aware of the worldwide rules for spectrum management and the need to obtain host nation permission for each transmitter and frequency assignment.
Program Managers need to ensure that spectrum access is adequate and that it is granted in the Continental United States (CONUS) and wherever else the equipment is deployed. The Pre-Milestone A Analysis of Alternatives (AoA) should address spectrum needs as part of concept formulation. Both the SSRA and DD-1494 are required for each milestone (see DoDI 4650.01). The SSRA is used within the DoD as the basis for assessing the feasibility of building and fielding equipment that operate within assigned frequency bands and to identify potential de-confliction situations. The DD-1494, Application for Equipment Frequency Allocation, has four stages, which reflect the increasing maturity of available spectrum information during development. The DD-1494 form is submitted to National Telecommunications and Information Administration (NTIA) for approval of spectrum allocation without which emitters cannot operate within CONUS, and to the International Telecommunications Union (ITU) for satellites. The NTIA Manual of Regulations and Procedures for Federal Radio Frequency Management (Redbook) chapter 3 addresses international treaty aspects of the spectrum and chapter 4 addresses frequency allocations.
The Systems Engineer has a lead role in defining spectrum needs, throughput and power requirements, and other attributes of the signals in space (outside the antenna – not in the transmission device) and the antenna characteristics and platform mounting details, as well as the safety aspects of emitters with regard to the Hazards of Electromagnetic Radiation to Ordnance (HERO), Personnel (HERP), and Fuel (HERF). The SE should be aware that portions of the spectrum previously assigned to DoD or other Federal users are being sold for commercial use. Thus, previously approved DD-1494 can be revoked, requiring modifications to designs, and even to fielded equipment. Similarly, host nations can alter prior agreements as commercial applications encroach upon previously available spectrum.
Each nation reserves the right to control emitters operating within its territory, thus host nation agreements are essential in support of deployment. Program Managers and Systems Engineers of platforms that mount multiple emitters and receivers need to obtain spectrum access for each emitter and ensure that those emitters and receivers do not produce mutual interference, or interact with ordnance (see DoDD 3222.3, MIL-STD-461, MIL STD-464, and MIL-HDBK-235-1, 237,and 240A, and “Joint Services Guide for Development of a Spectrum Supportability Risk Assessment”). The Defense Information Systems Agency (DISA), Defense Spectrum Organization provides spectrum support and planning for DoD and can be reached at http://www.disa.mil/Services/Spectrum. See Figure 4.3.18.20.F1 for spectrum activities by acquisition phase. This figure summarizes the requirements of DoDI 4650.01.
Figure 4.3.18.20.F1. Spectrum-Related Activities by Life-Cycle Phase