The primary focus of the Applied Engineering Division is to provide spectrum support to the warfighter; however, we also support other Department of Defense (DoD) and Federal agencies. Development or acquisition of spectrum-dependent systems that meet operational requirements, but fail to obtain spectrum supportability, means that the systems will not be allowed to be operated in the United States or in host nations. These systems create a potential for severe mutual interference between the system and other spectrum users, squander resources, and delay fielding of warfighting capabilities to field units. Successful fielding of a spectrum-dependent system depends upon approval of a program’s comprehensive assessment of the operational, regulatory, and technical aspects of the system’s use of the radio frequency (RF) spectrum.
As outlined in DoD Instruction 4650.01, all DoD Components shall obtain US Government (USG) certification of spectrum support prior to authorization to operate for experimental testing, developmental testing, or operations of spectrum dependent systems in the United States and its possessions (US&P). USG certification of spectrum support shall be obtained prior to submission of cost estimates (i.e., prior to Defense Acquisition System Milestone B) for development or procurement of major spectrum-dependent systems and for all space and satellite systems. In addition, some host nations require their own certification before providing authorization to operate. The USG Certification of spectrum support shall be obtained following completion of a comprehensive Spectrum Supportability Risk Assessment (SSRA).
The SSRA identifies and assesses spectrum issues with the potential to affect the required operational performance of the candidate system(s), assigns risks, and provides recommendations for mitigation measures to be taken.
The SSRA process consists of documenting the spectrum-dependent aspects of a system during the acquisition life cycle. A complete SSRA developed by the JSC will include the following components:
- Spectrum regulatory component: Addresses the compliance of the RF system with US national and international Tables of Frequency Allocations, compliance with regulatory agreements reached at the International Telecommunication Union, and determination of compliance of the system with pertinent national and international technical standards.
- Technical component: Initially quantifies potential mutual interactions between a candidate system and other co-band, adjacent band, and harmonically related RF systems, including the identification of suggested methods to mitigate the effects of possible mutual interference. Analysis includes initial frequency-distance (F-D) relationships and interference-to-noise (I/N) ratios that will require further study.
- Operational component: Identifies and quantifies the mutual interactions between a candidate system and the full complement of spectrum-dependent systems anticipated to be in the operational environment and provides suggested methods to mitigate possible instances of interference.
- E3 Assessment component: Identifies and quantifies the mutual interactions between the candidate system and systems anticipated to be in the operational environment. Analysis includes additional E3 disciplines such as Hazards of Electromagnetic Radiation to Personnel, Fuels, and Ordnance; electromagnetic pulse, lightning, etc.
The SSRA is required to be prepared, updated and submitted for approval to the appropriate Service review authority prior to each acquisition milestone and readiness review. The level of detail increases as the system’s design matures and as more information becomes available.
First submission – The first submission of the SSRA is prior to milestone A. The SSRA evaluates the acquisition’s spectrum needs versus national and international spectrum regulatory requirements and availability, as well as the spectrum certification stage and status of possible candidate spectrum-dependent systems.
Second submission – The second submission is prior to milestone B and provides increased specifics on the regulatory, technical, operational, and E3 components based on new information. With more refined information, modeling & simulation tools can be used to enhance decision making and provide insight into developmental testing.
Third submission – This submission occurs prior to milestone C and updates the second submission with more detailed spectrum and E3 analyses. A Stage 4 spectrum certification (DD Form 1494) is required prior to developing this SSRA.
Fourth submission – The fourth submission of the SSRA occurs prior to Full Rate Production (FRP). The components of the third submission will be updated with completed spectrum and E3 analyses. Risks will have been reduced to acceptable levels through mitigation mesasures. At this point, the system is ready for operational deployment.
Updated SSRA – SSRAs will be updated for readiness reviews and/or for production and fielded systems to reflect any changes to that new system, its operational deployment, host nation regulations, or modifications/upgrades of the system.
Spectrum Planning Guidance
The Applied Engineering Division of the JSC can provide spectrum planning support by completing frequency band studies and coordinating spectrum supportability for new spectrum-dependent systems. We can recommend the proper frequency band for your RF system that will optimize its chances for approval for operation in both national and international areas, or complete an analysis to determine the best frequency band an existing RF system must be relocated to. In addition, our knowledge of spectrum use and planning is underscored by our support to hundreds of DoD programs and our active role in the spectrum certification process by providing expert DD Form1494 support as described below.
A principal goal of the DoD’s spectrum management program is to develop and efficiently manage the DoD’s use of the spectrum during the frequency allocation, allotment, and assignment processes. Achieving this goal minimizes the potential for interference during the fielding and employment of spectrum-dependent equipment and is critical due to significant increases in the use of the available electromagnetic spectrum due to technological advancements and spectrum being reallocated away from military use, or being opened to sharing with commercial use.
The DD Form 1494 is submitted in stages that coincide with the phases of the DoD acquisition process and SSRA development. A short description of the DD Form 1494 stages follows:
Stage 1 - Conceptual: The initial planning effort has been completed, including identification of proposed frequency bands and other available characteristics. Certification of spectrum support for telecommunication systems at Stage 1 provides initial guidance on the feasibility of obtaining certification of spectrum supportability at subsequent stages.
Stage 2 - Experimental: The preliminary design has been completed. Radiation using “bread board” equipment or preliminary models may be required. Stage 2 certification is a prerequisite for receiving an experimental frequency assignment.
Stage 3 – Developmental: The major design has been completed and radiation may be required from “brass board” models during testing. Certification of spectrum supportability for RF systems at Stage 3 is a prerequisite for US national authorization of radiation in support of developmental testing of systems. It also provides guidelines for assuring certification of spectrum supportability at Stage 4. System parameters may be provided to host nations through COCOM spectrum offices for spectrum supportability comments.
Stage 4 – Operational: This stage identifies the final operating constraints or restrictions required to ensure compatibility when development has been essentially completed. Certification of spectrum supportability for RF systems at Stage 4 is a prerequisite for a frequency assignment for operational systems.
The Applied Engineering Division of the JSC can assist in identifying and defining the appropriate equipment characteristics/technical parameters and preparing the DD1494 Form for submission to the Military Communications-Electronics Board (MCEB).
Operational System Performance
Our engineers use frequency assignment and equipment technical characteristics databases as well as computer modeling tools to assist in the planning of training exercises or contingencies by developing frequency plans and restricted frequency lists. We also can predict radio propagation, radar coverage, and datalink performance based on terrain and environmental constraints. Our planning expertise will ensure military operations are not hampered by harmful electromagnetic interference interactions.
Test and Measurement
The Applied Engineering Division has the capability to provide systems monitoring support and measurement of signal levels in the field, and can identify sources of interference and recommend measures to mitigate the interference. In addition, we can provide tailored MIL-STD-461 testing of systems and components in the laboratory.