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Government Frequency Usage

                                  APPENDIX D

    This section summarizes the Federal spectrum use of the various bands 
between 75-1400 MHz frequency range allocated for Federal Government fixed 
and mobile services. Frequency bands that serve a major common function are 
grouped together for convenience of discussion.
    The information is based jointly on data provided by the Federal agencies 
and the data records contained in the NTIA Government Master File (GMF) of 
frequency assignments. While some information is presented in terms of the 
number of Federal frequency assignments, it should be noted that the number 
of actual radio equipment will exceed, and sometimes far exceed, the number 
of assignments in a band, since one frequency assignment may represent many 
radio equipment. The Federal assignment data used in the spectrum use 
assessment are current as of October 1993. 
118-137 MHz BAND
    Internationally and nationally, the 117.975-137 MHz frequency range is 
allocated to the aeronautical mobile service on a primary basis. Nationally, 
the 121.9375-123.0875 MHz, 128.8125-132.0125 MHz and a portion of the 136-137 
MHz frequency bands, which represent a total bandwidth of 4.85 MHz, are 
exclusively allocated for use by the non-Federal, and the remaining portion of 
the overall band is shared by the Federal Government and non-Federal entities 
on a co-equal basis. The entire band has a total bandwidth of 19.025 MHz and 
13.675 MHz of bandwidth is designated for shared use; no portion of this band 
is allocated exclusively for Federal Government use.

    Aeronautical mobile service spectrum requirements are accommodated mostly 
in the HF (3-23 MHz) and VHF (117.975-137 MHz) portion of the radio spectrum. 
The VHF band provides the primary communications mode for Air Traffic Service 
(ATS) and Aeronautical Operational Control (AOC) safety communications for all 
areas of the world where radio line-of-sight services can be established. In 
the United States, this band is used by Federal Aviation Administration to 
provide ATS safety communications and by users such as, the airlines, business 
aviation, and general aviation to provide AOC safety communications. Each 
communications frequency is re-used as often as possible (due to the fixed 
number of available frequencies) so that continuous coverage can be established 
to support air traffic control systems. The FAA maintains an extensive network 
of over 3,050 VHF radio stations giving reliable coverage over the most areas 
of the United States.
138-150.8, 162.0125-174, 220-222 AND 406.1-420 MHz BANDS
    Federal Government land mobile communication requirements are accommodated 
in segments of the following bands which are allocated to the fixed and mobile 
services for non-tactical use: 138-144, 148-149.9, 150.05-150.8, 162.0125-174, 
220-222, and 406.1-420 MHz. Federal Government agencies use the fixed and 
mobile radio systems that operate in these bands to accomplish a variety of 
missions that serve the public. The approximately 80,000 frequency assignments 
throughout these bands represent over one million Federally-owned radios. Since 
the dominant bands used by the Federal agencies for land mobile operations are 
the 162.0125-174 MHz and 406.1-420 MHz bands, the list of major users presented 
in Table D-1 only accounts for these two bands. The "Others" category includes 
Federal agencies with 20 or less assignments.
    Federal mobile radio systems use a wide range of equipment types in a 
variety of geographic environments for voice and data communications. Common 
types of equipment include base and repeater stations, mobile stations, and 
hand-held portable stations. In nearly all cases, this equipment is the same
type of off-the-shelf equipment used by local and state public safety agencies. 

    Mission requirements often lead to worldwide and nationwide, as well as 
local service areas that range in natural character from remote to urban. 
Federal Government missions are mandated by Congress and the President, and 
generally have no counterparts outside the Federal Government. The closest are 
the state and local governments with similar missions that own and operate 
their own systems. The major differences lie in two areas: (1) the national 
security operations and wide area safety services of the Federal Government, 
and (2) the geographic areas of communication coverage required.

  Table D-1. Major Federal Users of the 162.0125-174 MHz and 406.1-420 MHz
                                            Total Number of Assignments
  Federal Agency                        162.0125-174 MHz      406.1-420 MHz
  --------------                        ----------------      -------------
  Agriculture                                  9,154              1,555
  Air Force                                    1,645              1,935
  Army                                         3,351              2,243
  Commerce                                     2,300              1,379
  Coast Guard                                    917                308
  Energy                                       2,420              1,816
  Environmental Protection Agency                124          See "Others"
  Federal Aviation Administration              4,024              1,336
  Federal Communications Commission              114                  0
  Federal Emergency Management Agency             25                 26
  Federal Reserve System                          22                 96
  Government Services Administration              73                496
  Health and Human Services                      285                120
  Interior                                     7,929              1,253
  International Boundary Water Commission         55          See "Others"
  Justice                                     17,204              4,358
  Labor                                           52                 48
  Navy                                           396                872
  National Aeronautics and Space Adm.            215                191
  Nuclear Regulatory Commission                  215          See "Others"
  National Science Foundation                     59          See "Others"
  State                                           53                 58
  Smithsonian Institution                         22          See "Others"
  Treasury                                     5,090              1,906
  Transportation                                 238                 35
  Tennessee Valley Authority                     467                285
  United States Information Agency         See "Others"              71
  United State Postal Service                    804                896
  Veterans Administration                        793                343
  "Others"                                       120                513

    Federal Government radio systems support agency mission requirements in 
the following broad categories: law enforcement, transportation, natural 
resources, emergency and disaster services, utilities, medical, and 
administrative. Federal Government radio systems are usually multi-purpose 
systems; e.g., law enforcement, natural resource, medical, administration, 
and utility functions may be supported on the same radio system, thus 
increasing their spectrum efficiency. Federal Government land mobile 
requirements for each of the above categories are described in the following 
Law Enforcement
    Federal law enforcement radiocommunications requirements include everything 
from hand-held portable communications between internal security posts to 
nationwide/worldwide airborne communications for drug interdiction and 
protection of the President. Federal law enforcement radiocommunications must
be immediate; delay is not acceptable.
    Effective and reliable radiocommunications are required for safety-of-life 
and property protection of Federal building complexes, Federal lands, military 
bases, and other types of installations. A major use of dedicated 
radiocommunications is the security of current and former Presidents and family 
members, as well as the Vice President and family, and other distinguished 
persons including foreign heads of state.
    Operations requiring high priority communications include movement of 
protected individuals, in response to violent crimes (bank robbery or 
kidnapping), undercover surveillance, and arrests. Cases involving 
counterintelligence, personal crimes, organized crimes, drug interdiction, 
fugitives, hostage situations, terrorism, smuggling, guns and explosives, 
counterfeiting, fraud, forgery and tax evasion also require immediate 
communications. Additionally, portable radios and body transmitters are used 
inside prisons for prisoner control activities, and by special agents to 
support investigative functions, and in personnel and property security 
    Most Federal law enforcement agencies have area offices that are 
responsible for activities throughout a geographic region. Repeaters and radio 
links are installed to obtain the necessary radiocommunications coverage within 
that region. Repeater systems are installed throughout urban areas in these 
regions to permit necessary portable radiocommunications. Transportable 
equipment is provided to respond to impromptu travel requirements in support 
of personnel protection or pursuit of criminal cases, special cases, or other 
major crises such as Waco, Texas, and the bombing of the New York City World 
Trade Center in early 1993.
    Federal law enforcement systems require communications with privacy. The 
monitoring of clear voice communications by the general public, the news media, 
foreign intelligence agents, and criminals has disrupted investigations and 
caused life-threatening situations for law enforcement personnel and innocent 
victims. Digital encryption, spread spectrum and other techniques are now 
utilized to assure transmissions are not compromised.
    Installation of radio systems that provide complete coverage of the United 
States is not spectrum-efficient. However, the mandated missions of Federal law 
enforcement agencies require the capability to deploy and install both 
permanent and temporary facilities when and wherever needed, not only 
nationwide but worldwide. This is accomplished through agency-dedicated means, 
including full and complete control of installations, operations, and 
maintenance by the various elements of the law enforcement community.
    Federal activities in aviation, maritime, highways, and railroads have a 
heavy investment in both fixed and land mobile operations. Aviation-sector 
land mobile applications include maintenance, safety, and inspection using 
portable and mobile radios, and repeaters and base station facilities; remote
maintenance monitoring equipment; remote control of robot devices at supply 
depots; airport runway light control systems and windshear alert systems. These 
systems are installed in airports and airway facilities for management and 
coordination activities. The systems use both voice and data to: automate
equipment monitoring; perform safety-of-life, anti-terrorist, and air security 
functions; integrate air traffic control communications within the centers and 
control towers; and conduct various airport and airfield communications as 
necessary, tailored to the needs of each airport/airway location.
    Federal maritime management coordination, safety, and law enforcement 
activities also use radios operating in Federal land mobile bands. These 
activities require nationwide implementation, although many operations are 
concentrated in seaports, docks, and waterways of the nation's coastal areas, 
major rivers, and the Great Lakes region.
    Federal surface transportation operations provide a variety of management 
and oversight support to coordinate activities at various highway and rail 
sites. Many of these functions are mandated by law and nationwide in scope.
Natural Resources
    The Federal Government manages its natural resource programs using 
radiocommunications to accomplish Congressionally-mandated missions. Fixed 
stations, mobiles, handheld portables, and transportable repeaters and base 
stations make up these radio systems. These operations are spread throughout 
the United States and Possessions, in suburban, urban and rural sometimes 
remote and almost inaccessible areas. Some systems encompass only a few 
buildings in a city or a small wildlife refuge. Others encompass large 
geographical areas, such as, the national forests, Indian reservations, and
national parks; multiple counties or states, such as the Tennessee Valley 
Authority; or are nationwide in nature.
    These systems provide for the safety of the public and Federal Government 
personnel; monitoring and distribution of water; management of timber growth 
and harvest; protection, operation, and management of our national parks, 
national forests, range and grass lands, wildlife refuges; protection and 
management of wildlife and fisheries; recreation; surveying and mapping; 
protection of Native Americans and protection and management of their lands; 
forestry and range management; and assessment of mineral deposits. Wildlife 
monitoring and tracking to protect endangered and threatened species and to 
control animal damage are performed in these bands with transmitters as small 
as dimes or as large as softballs. 
    Emergency situations such as fires, hurricanes, earthquakes, volcanic 
eruptions, etc., place great demands on the existing communication systems 
each year and routinely require the use of emergency backup systems. These 
emergencies sometimes require a tenfold expansion of communications facilities 
in a matter of hours. This separate function is described in greater depth in 
the next section.
Emergency and Disaster Services
    The Federal Government provides an array of emergency and disaster response 
communications capabilities to protect the American public and resources from 
natural disasters and technological hazards. This involves a wide range of 
missions including prevention, mitigation, preparedness, response and recovery. 
These services involve virtually every department and agency of the Federal 
government. Where safety of life and property is at risk, communication systems 
that can operate reliably even when normal systems are disrupted are essential. 
Spectrum-dependent emergency radio systems are the only systems capable of 
providing the essential levels of reliability, mobility, and flexibility during 
crises. A significant number of the Federal Government emergency and disaster 
response communications systems interface with state and local governments as 
well as with national volunteer organizations such as the Red Cross, amateur 
radio operators and similar groups. An important consideration in managing 
these emergency assets is the need to conduct periodic exercises to ensure 
they work when required.
    Many specialized emergency requirements have unique spectrum-dependent 
needs that must also be satisfied by the nationwide dedication of radio 
spectrum for that purpose. As an example, Federal, state, and local government 
search and rescue teams deploying to the site of a national emergency or 
disaster need reliable communications to locate victims in collapsed buildings, 
administer medical and lifesaving treatment and relocate them to safety or 
medical facilities.
    Providing the communications needed during major natural and technological 
emergencies requires a significant quantity of readily deployable land mobile 
radiocommunications. Major natural disasters occur on a continuing basis. Major 
disasters, such as Hurricanes Andrew and Hugo, the San Francisco earthquake, 
and the recent floods in the Mississippi Valley have required the deployment of 
thousands of radios. These have been Federal Government-owned land mobile 
radios used to effectively coordinate and provide emergency management during 
the readiness, response and recovery phases of major natural and manmade 
disasters. Land mobile radios are critical for providing the needed level of 
flexibility and survivability required. Dedicated, reliable non-blocked 
resources are required to support these time-sensitive, high demand operations 
to improve rapid response, to minimize interference, and to safeguard 
emergency response personnel and the delivery of life saving services to the 
general public.
    Federal Government utility operations which provide essential services to 
both Federal Government and non-Federal users are also supported in these 
bands. These operations include generation of electric power at fossil, hydro, 
and nuclear power plants; the distribution of electrical energy and the 
maintenance of distribution lines; and the distribution of potable and 
agricultural waters and the maintenance of these systems. 
    The distribution of electrical energy from the generating plants to the 
load centers and the interconnection of bulk electrical power supply systems 
for reliability and adequacy has required the development of complex, 
supportive radio systems. Communications must be of the highest level of 
reliability, economically and technically feasible, and must be instantly 
available for the successful operation of these electrical power systems. 
    Radiocommunications systems are also vital to the operation and maintenance 
of water distribution and sewage systems on military bases, water distribution 
systems encompassing aqueducts and canals in arid areas, and dams for the 
control of flooding. Radio systems provide for collection of water flow and
salinity data and control of irrigation ditch gates and pumping stations for 
the management of vast water distribution systems and the maintenance of these 
systems. Dam safety data is transmitted to central processing points to provide 
early warning of potential dangers and scheduling of maintenance. Day-to-day 
operations of these systems with limited field personnel resources provide for 
efficient and timely response to changing customer requirements.
    The criticality coupled with the remote areas encompassed by many of these 
systems have generally precluded the availability of cost effective support 
from commercial communications providers. 

    The Federal Government provides essential land mobile radiocommunications 
for medical facilities. Reliable radiocommunications are required to provide 
life-or-death medical care along with the daily operations of a medical center. 
Radio paging communications are essential to obtain doctors and nurses during 
emergency situations. Two-way radiocommunications are required to interact with 
local governments to provide security, fire protection and maintenance. 
Reliable radiocommunications are required for local, Federal Government, 
civilian, and military medical facilities to interact with each other to 
provide essential emergency medical care.
     Administrative communications is the descriptive term for various support 
type communications used for administrative management of personnel or material 
required in performing Federal Government missions. All Federal Government 
agencies employ some type of administrative land mobile communications systems 
within their respective departments. Examples of these support communication
systems include base stations for VIP management and control of operations and 
test-range safety, wireless microphones, maintenance communications, motorpool, 
building guards, and paging. These systems use fixed and transportable base 
stations and repeaters, mobiles and handheld portables.
Fixed Uses
    The Federal Government fixed uses in these bands include the collection of 
seismic, meteorological, and hydrologic data for the forecast of volcanic 
eruptions and earthquakes; identification of potential fire danger areas; and 
prediction of availability of water for agricultural and public use. These data 
are provided to state and local officials for planning and emergency operation 
purposes. National Oceanic and Atmospheric Administration (NOAA) Weather Radio, 
which provides the public with up-to-date weather information, also operates in 
the 162-174 MHz band.
216-220 MHz BAND
    The 216-220 MHz band is allocated to the Federal Government and non-Federal 
for the maritime mobile service on a shared, primary, co-equal basis. Fixed and 
aeronautical mobile services are also shared by the Federal Government and 
non-Federal on a secondary basis. Federal Government radiolocation is also 
permitted in the band on a secondary basis, but limited to the military 
services. Non-Federal government land mobile operations are also permitted in 
the band on a secondary basis.
    In the 216-220 MHz band, there is a total of 1160 assignments, 
approximately 40% of which are for Federal Government operations. Table D-2 
shows the major Federal users of the band. Any agency with less than 10 
assignments is not included. The Departments of Energy and Interior are the 
major Federal users, primarily for telemetry systems in the fixed and mobile 
services for low power seismology operations. These systems are deployed 
throughout the United States.
        TABLE D-2. Major Federal Users of the 216-220 MHz Band.
 Freq. Band    Federal Government Agencies/Total Number of Assignments
   (MHz)     Air Force   Army   Energy   Interior   Navy   NASA   Others
 ----------  ---------   ----   ------   --------   ----   ----   ------ 
  216-220       21        12      301       101      12     11      19
225-400 MHz BAND
    The 225-400 MHz band consists of several band segments. The 225-328.6 MHz 
and 335.4-399.9 MHz are allocated to the Federal Government for fixed and 
mobile services on a primary basis. Some portions of these segments are also 
allocated for military mobile-satellite use. The segments 328.6-335.4 MHz
and 399.9-400 MHz are allocated to the Federal Government and non-Federal on 
a shared, primary basis for aeronautical radionavigation and radionavigation-
satellite services, respectively. Discussions on the latter two services were 
presented in Section 2 under the radionavigation category. 
    There are more than 23,000 frequency assignments currently authorized in 
the 225-328.6 MHz and 335.4-399.9 MHz segments of the band. Seventy-five 
percent of the total assignments belong to the DoD, as can be seen in Table 
D-3. In the Table, the "Others" category includes those agencies with 20 or 
less assignments. The FAA, with 23% of the total assignments, is the other 
major user of these portions of the 225-400 MHz band. Seventy percent of the 
military use are for air-ground-air, air traffic control, shipboard line-of-
sight, and tactical and strategic forces satellite communications. The FAA's
assignments are in direct support to the military air traffic control.
    The 225-400 MHz band is the single most critical spectrum resource for the 
military tactical forces, both nationally and within NATO. The DoD operates 
approximately 75,000 radio equipments supporting its operational requirements 
in the band. Extensive peacetime training and alert exercises are conducted by
the military to maintain their combat readiness. The band is standardized with 
U.S. military allies in Europe and elsewhere for interoperability during 
combined actions and is extensively used for a wide variety of functions, 
including forward area tactical radio relay, airborne, land-based and satellite
              TABLE D-3. Major Users of the 225-400 MHz Band.
                                         Total Number of Assignments
  Federal Agencies                 225-328.6 (MHz)        335.4-399.9 (MHz)
  ----------------                 ---------------        -----------------
  Air Force                             4,555                   2,076
  Army                                  2,532                   1,424
  Coast Guard                             134                     176
  Energy                                   75                      20
  Federal Aviation Adm.                 3,537                   1,860
  Navy                                  5,153                   1,603
  NASA                                     35                      25
  Others                                   46                       3

    The FAA uses the band for the control of DoD aircraft within the National 
Airspace because very few military aircraft have VHF aeronautical band radios. 
The Coast Guard also uses this band on all its aircraft to support air-ground-
air communications. On every flight, these aircraft actively use and depend
upon channels provided especially in the 380-399.9 MHz portion of the band. An 
estimated 45,000 flights per year is made for missions including search and 
rescue operations, drug interdiction and other law enforcement, marine 
environmental protection, International Ice Patrol, alien interdiction, 
National defense, and support of other Federal Government agencies.
932-935 MHz and 941-944 MHz BANDS
    Both bands are allocated to the Federal Government and non-Federal for the 
fixed service on a shared primary basis. In addition, Government off-shore 
radiolocation operation is permitted on a non-interference basis and limited 
to the military services. The 932-935 MHz and 941-944 MHz bands are two of the 
few bands supporting fixed low-capacity communication links. Spectrum use for 
every agency is similar in both the 932-935 MHz and 941-944 MHz bands. Usually, 
a transmit frequency in one band has a corresponding receive frequency in the 
other band or a paired channel.
    The main users of the bands are listed in Table D-4. As shown, FAA and 
Agriculture are the dominant users with an approximate combined 76% of the 
total assignments in both bands. The other significant users are Energy and 
Interior. The "Others" category includes those agencies with 10 or less 
    FAA uses these bands for low density communications links (voice and/or 
data). The majority of their assignments are authorized for the Low Density 
Radio Communication Link (LDRCL) system, which are deployed across the United 
States, in support of the National Airspace System. Agriculture's assignments, 
however, are concentrated on the West Coast and in the North-central States. 
These assignments are in support of their point-to-point, microwave backbone 
communications systems. The DOE also operates microwave systems specially in 
remote areas of the United States where their operation is not accessible by 
telephone. For example, in the control of operation, maintenance, management 
and distribution of electric power. In addition, DOE employs telemetering fixed 
systems for weather data transfer. These bands also support DOE's emergency 
functions. The Interior's backbone microwave systems are directly in support 
of law enforcement activities and for their dispatch systems for resource 
management and fire suppression.
      TABLE D-4. Major Users of the 932-935 MHz and 941-944 MHz Bands.
                                    Total Number of Assignments
  Federal Agencies                  932-935 MHz     941-944 MHz
  ----------------                  -----------     -----------
  Agriculture                           158             153
  Coast Guard                            11              11
  Energy                                 52              48
  Federal Aviation Administration       302             305
  Interior                               44              45
  Navy                                   14              15
  Treasury                               15              15
  Others                                 10               8
1350-1400 MHz BAND
    This band is allocated exclusively to the Federal Government for fixed, 
mobile, and radiolocation services on a primary basis. Federal Government 
operations in these services are limited to the military forces, although FAA 
has few assignments for surveillance radars needed for air traffic control. In
addition, the discrete frequency at 1381.05 MHz is allocated to the fixed and 
mobile-satellite services for space-to-Earth relay of nuclear burst data.
    The 1350-1400 MHz band is primarily used by the Army for tactical training. 
For example, out of the approximately 690 assignments, about 508 assignments 
(74%) belong to the Army in support of tactical radio relay systems. The Air 
Force also has assignments for tactical radio relay systems but, the major
Air Force system in this band is the Range Applications Joint Program Office 
(RAJPO) data link. This system, which cost about $100 million and also operates 
in the 1429-1435 MHz band, provides real-time GPS data to designated military 
test ranges. RAJPO is currently the only known system to fully support advanced 
space weapons systems development like the Strategic Defense Initiative. Other 
major systems supported by RAJPO are advance fighter technology integration, 
all stealth developments, advanced tactical aircraft, AEGIS, and sonar and 
antisubmarine warfare. The RAJPO has a tuning range capability between 1350-
1450 MHz. This system will be deployed at all major military test ranges and 
provide, in conjunction with the Global Positioning System, high accuracy 
position location, target tracking and other uses. 
From: /pub

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