Technical Topics, January 2004
FEMA Supports Shortwave Listeners
The Federal Emergency Management Agency (FEMA) has filed comments with the FCC, supporting the position of NASWA. FEMA is opposed to deployment of broadband Internet access via power lines (BPL). FEMA’s ability to use the HF spectrum is regulated by the National Telecommunications and Information Administration (NTIA).
Like NASWA, FEMA recommends that Part 15 signal level limits be tightened instead of being relaxed, “FEMA believes and recommends that Part 15 of the FCC rules and regulations should be strengthened to ensure that there will be no increase in interference levels to existing communications systems which are licensed by the FCC or authorized by the NTIA.”
FEMA is an organizational element of the Department of Homeland Security. Because FEMA’s mission concerns public safety, their opposition to BPL should carry plenty of weight with the FCC and provide powerful grounds for an appeal to the Congress if the FCC chooses to ignore FEMA’s and NASWA’s concerns.
FEMA owns, operates, and maintains a very large high frequency radio system known as the FEMA National Radio System (FNARS). FNARS is the primary command and control backup communications media for this agency and interfaces with the other departments and agencies as specified in the Federal Response Plan in furtherance of the purposes of the Robert T. Stafford Disaster Relief and Emergency Assistance Act, as amended (42 U.S.C. §5121 et sequentia) and the Department of Homeland Security Act of 2002, Public Law No. 107-296.
FNARS is used to communicate with disaster response elements at the federal, state, and local levels. The federal government relies on FNARS for communications, both for natural and man-made disasters. The safety, health and welfare of our citizenry are directly tied to the successful execution of our communications programs. FNARS directly supports the federal Continuity of Government (COG) and Continuity of Operations programs (COOP) as required by Executive Order and various Presidential Decision Directives. FNARS is essential to other federal departments and agencies in terms of fulfilling their respective national security and emergency preparedness (NS/EP) responsibilities.
FEMA has concluded that introduction of unwanted interference from the implementation of BPL technology into the high frequency radio spectrum will result in significant detriments to the operation of FEMA radio systems such as FNARS.
The unavoidable radiation from power lines and associated modems raises noise floor limits to an unacceptable level. This interference will severely impair FEMA’s mission-essential HF radio operations in areas serviced by BPL technology. Tests have shown that in order for licensed transmitters to compensate for this noise level, there would have to be an increase in the signal level on the order of +30dB.
FNARS utilizes transmitters that range from 1 kW to 10 kW in output power. An increase in power of +30 dB to offset the increased noise floor would require a 10 kW station to increase power output to 1 megawatt. The maximum HF power level that the NTIA will authorize is 10 kW for emergency operations, and only 3 kW for normal operations. Thus, the +30 dB increase is far beyond the level authorized by the NTIA and FNARS will not be able to compete with the encroachment of signals produced by BPL technology and devices.
FNARS is designed to provide a defined level of performance in communications using current the authorized and licensed power levels, while expecting existing interference from known licensed and unlicensed devices. Any implementation of increased power for FNARS is undesirable and is unnecessary under existing circumstances. A power increase to offset the BPL systems, however, would require acquisition of new transmitter equipment and antenna systems designed for these power increases, and would also present significant safety problems to personnel. Solving these problems would require a considerably higher budget for FNARS and result in unnecessary extra costs to the US Government.
FNARS radio operators normally conduct communications with signals that are barely above the ambient noise levels. The ambient noise level at the receiver is thus the determining factor as to whether stations can communicate. FEMA believes the FCC should not take actions that would result in any increase in the noise floor of the HF radio spectrum, because any noise increase inevitably would diminish the ability to maintain essential communications. This loss of communication would directly impair the safety of life and property.
FNARS HF radio stations are normally located in residential areas that would be serviced by Power Line Communication (PLC) systems. FEMA also utilizes HF radio stations from other Government programs, including the Military Affiliate Radio System (MARS), the US Air Force Auxiliary–Civil Air Patrol (CAP), and the Radio Amateur Civil Emergency Service (RACES), which are similarly situated. The interference from PLC would render these essential communications services useless.
In radio frequency interference situations, there is a reciprocal condition present. A system that exhibits unintentional radiation may also susceptible to the incursion of unwanted signals. FEMA’s receivers will inevitably suffer interference from BPL radiation, and BPL users will experience service interruption when FEMA’s transmitters overpower the signal levels expected by BPL modems.
When interference from BPL systems occurs, which FEMA believes would be the result if the FCC adopts the proposal, questions will arise concerning how resulting interference problems are to be resolved, and by whom. FEMA believes the licensed radio services will be perceived by consumers as responsible for the interference, since most consumers do not understand that their unlicensed Part 15 devices must accept any interference received, including interference that may cause undesired operation.
The HF spectrum is a unique resource for survivable, long-distance fixed and transportable communications that are independent of fragile infrastructure. Other communications media cannot meet FEMA’s requirements for disaster response and other mission-critical communications. Other users of the HF spectrum are similarly affected by the proposal, and only HF radio can meet their needs as well.
Implementation of BPL under the present or relaxed emission restrictions would make HF radio unusable, depriving our nation of an invaluable and irreplaceable public safety resource. The purported benefits of BPL in terms of expanded services in certain communications sectors do not appear to outweigh the benefit to the overall public of HF radio capability as presently used by Government, broadcasting, and public safety users.
By this time next month, the NTIA is expected to weigh in on BPL. When they do, we will cover their comments right here in the NASWA Journal. Stay tuned.