| a |
atto (10-18) |
 |
angstrom |
| A |
ampere |
| AAR |
automatic alternate routing |
| AARTS |
automatic audio remote test set |
| ABCA |
American, British, Canadian, Australian [armies] |
| ac |
alternating current |
| ACA |
automatic circuit assurance |
| ACC |
automatic callback calling |
| ACD |
automatic call distributor |
| ac-dc |
alternating current - direct current |
| ACK |
acknowledge character |
| ACTS |
Advanced Communications Technology Satellite |
| ACU |
automatic calling unit |
| A-D |
analog-to-digital |
| ADC |
analog-to-digital converter
analog-to-digital conversion |
| ADCCP |
Advanced Data Communication Control Procedures |
| ADH |
automatic data handling |
| ADP |
automatic data processing |
| ADPCM |
adaptive differential pulse-code modulation |
| ADPE |
automatic data processing equipment |
| ADPSSO |
automatic data processing system security officer |
| ADU |
automatic dialing unit |
| ADX |
automatic data exchange |
| AECS |
Aeronautical Emergency Communications System [Plan] |
| AF |
audio frequency |
| AFC |
area frequency coordinator
automatic frequency control |
| AFNOR |
Association Français Normal |
| AFRS |
Armed Forces Radio Service |
| AGC |
automatic gain control |
| AGE |
aerospace ground equipment |
| AI |
artificial intelligence |
| AIG |
address indicator group
address indicating group |
| AIM |
amplitude intensity modulation |
| AIN |
advanced intelligent network |
| AIOD |
automatic identified outward dialing |
| AIS |
automated information system |
| ASIC |
application-specific integrated circuits |
| AJ |
anti-jamming |
| ALC |
automatic level control
automatic load control |
| ALE |
automatic link establishment |
| ALU |
arithmetic and logic unit |
| A/m |
amperes per meter |
| AM |
amplitude modulation |
| AMA |
automatic message accounting |
| AMC |
administrative management complex |
| AME |
amplitude modulation equivalent
automatic message exchange |
| AMI |
alternate mark inversion [signal] |
| AM/PM/VSB |
amplitude modulation/phase modulation/vestigial sideband |
| AMPS |
automatic message processing system |
| AMPSSO |
automated message processing system security officer |
| AMSC |
American Mobile Satellite Corporation |
| AMTS |
automated maritime telecommunications system |
| ANI |
automatic number identification |
| ANL |
automatic noise limiter |
| ANMCC |
Alternate National Military Command Center |
| ANS |
American National Standard |
| ANSI |
American National Standards Institute |
| AP |
anomalous propagation |
| APC |
adaptive predictive coding |
| APD, apd, a.p.d. |
avalanche photodiode |
| API |
application program interface |
| APL |
average picture level |
| APK |
amplitude phase-shift keying |
| ARP |
address resolution protocol |
| ARPA |
Advanced Research Projects Agency [now DARPA] |
| ARPANET |
Advanced Research Projects Agency Network |
| ARQ |
automatic repeat-request |
| ARS |
automatic route selection |
| ARSR |
air route surveillance radar |
| ARU |
audio response unit |
| ASC |
AUTODIN Switching Center |
| ASCII |
American Standard Code for Information Interchange |
| ASN.1 |
abstract syntax notation one |
| ASP |
Aggregated Switch Procurement
adjunct service point |
| ASR |
automatic send and receive
airport surveillance radar |
| AT |
access tandem |
| ATACS |
Army Tactical Communications System |
| ATB |
all trunks busy |
| ATCRBS |
air traffic control radar beacon system |
| ATDM |
asynchronous time-division multiplexing |
| ATE |
automatic test equipment |
| ATM |
asynchronous transfer mode |
| ATV |
advanced television |
| au |
astronomical unit |
| AUI |
attachment unit interface |
| AUTODIN |
Automatic Digital Network |
| AUTOSEVOCOM |
Automatic Secure Voice Communications Network |
| AUTOVON |
Automatic Voice Network |
| AVD |
alternate voice/data |
| AWG |
American wire gauge |
| AWGN |
additive white Gaussian noise |
| AZ |
azimuth |
| b |
bit |
| B |
bel
byte |
| balun |
balanced to unbalanced |
| basecom |
base communications |
| BASIC |
beginners' all-purpose symbolic instruction code |
| BCC |
block check character |
| BCD |
binary-coded decimal
binary-coded decimal notation |
| BCI |
bit-count integrity |
| Bd |
baud |
| B8ZS |
bipolar with eight-zero substitution |
| bell |
BEL character |
| BER |
bit error ratio |
| BERT |
bit error ratio tester |
| BETRS |
basic exchange telecommunications radio service |
| BEX |
broadband exchange |
| BIH |
International Time Bureau |
| B-ISDN |
broadband ISDN |
| bi-sync |
binary synchronous [communication] |
| bit |
binary digit |
| BIT |
built-in test |
| BITE |
built-in test equipment |
| BIU |
bus interface unit |
| BNF |
Backus Naur form |
| BOC |
Bell Operating Company |
| BPSK |
binary phase-shift keying |
| bpi |
bits per inch
bytes per inch |
| b/s |
bits per second |
| b/in |
bits per inch |
| BPSK |
binary phase-shift keying |
| BR |
bit rate |
| BRI |
basic rate interface |
| BSA |
basic serving arrangement |
| BSE |
basic service element |
| BSI |
British Standards Institution |
| B6ZS |
bipolar with six-zero substitution |
| B3ZS |
bipolar with three-zero substitution |
| BTN |
billing telephone number |
| BW |
bandwidth |
| c |
centi (10-2) |
| CACS |
centralized alarm control system |
| CAM |
computer-aided manufacturing |
| CAMA |
centralized automatic message accounting |
| CAN |
cancel character |
| CAP |
competitive access provider
customer administration panel |
| CARS |
cable television relay service [station] |
| CAS |
centralized attendant services |
| CASE |
computer-aided software engineering
computer aided system engineering
computer-assisted software engineering |
| CATV |
cable TV
cable television
community antenna television |
| CBX |
computer branch exchange |
| C2 |
command and control |
| C3 |
command, control and communications |
| C3CM |
C3countermeasures |
| C3I |
command, control, communications and intelligence |
| CCA |
carrier-controlled approach |
| CCD |
charge-coupled device |
| CCH |
connections per circuit hour |
| CCIF |
International Telephone Consultative Committee [a predecessor to
the CCITT] |
| CCIR |
International Radio Consultative Committee |
| CCIS |
common-channel interoffice signaling |
| CCIT |
International Telegraph Consultative Committee [a predecessor to
the CCITT] |
| CCITT |
International Telegraph and Telephone Consultative Committee {now
ITU-T} |
| CCL |
continuous communications link |
| CCS |
hundred call-seconds |
| CCSA |
common control switching arrangement |
| CCTV |
closed-circuit television |
| CCW |
cable cutoff wavelength |
| cd |
candela |
| CD |
collision detection, compact disk |
| CDF |
combined distribution frame
cumulative distribution function |
| CDMA |
code-division multiple access |
| CDPSK |
coherent differential phase-shift keying |
| CDR |
call detail recording |
| CD ROM |
compact disk read-only memory |
| CDT |
control data terminal |
| CDU |
central display unit |
| C-E |
communications-electronics |
| CEI |
comparably efficient interconnection |
| CELP |
code-excited linear prediction |
| CEP |
circular error probable |
| CFE |
contractor-furnished equipment |
| cgs |
centimeter-gram-second |
| ChR |
channel reliability |
| CIAS |
circuit inventory and analysis system |
| CIC |
content indicator code |
| CIF |
common intermediate format |
| CIFAX |
ciphered facsimile |
| CINC |
commander-in-chief |
| ciphony |
ciphered telephony |
| CiR |
circuit reliability |
| C/kT |
carrier-to-receiver noise density |
| CLASS |
custom local area signaling service |
| cm |
centimeter |
| CMI |
coded mark inversion |
| CMIP |
Common Management Information Protocol |
| CMIS |
common management information service |
| CMOS |
complementary metal oxide substrate |
| CMRR |
common-mode rejection ratio |
| CNR |
carrier-to-noise ratio
combat-net radio |
| CNS |
complementary network service |
| C.O. |
central office |
| COAM |
customer owned and maintained equipment |
| coax |
coaxial cable |
| COBOL |
common business oriented language |
| codec |
coder-decoder |
| COG |
centralized ordering group |
| COMINT |
communications intelligence |
| COMJAM |
communications jamming |
| compandor |
compressor-expander |
| COMPUSEC |
computer security |
| COMSAT |
Communications Satellite Corporation |
| COMSEC |
communications security |
| CONEX |
connectivity exchange |
| CONUS |
Continental United States |
| COP |
Committee of Principals |
| COR |
Council of Representatives |
| COT |
customer office terminal |
| CPAS |
cellular priority access services |
| CPE |
customer premises equipment |
| cpi |
characters per inch |
| cpm |
counts per minute |
| cps |
characters per second
cycles per second [deprecated] |
| CPU |
central processing unit
communications processor unit |
| CR |
channel reliability
circuit reliability |
| CRC |
cyclic redundancy check |
| CRITICOM |
Critical Intelligence Communications |
| CROM |
control read-only memory |
| CRT |
cathode ray tube |
| c/s |
cycles per second [deprecated] |
| CSA |
Canadian Standards Association |
| CSC |
circuit-switching center
common signaling channel |
| CSMA |
carrier sense multiple access |
| CSMA/CA |
carrier sense multiple access with collision avoidance |
| CSMA/CD |
carrier sense multiple access with collision detection |
| CSU |
channel service unit
circuit switching unit
customer service unit |
| CTS |
clear to send |
| CTX |
Centrex ® [service]
clear to transmit |
| CVD |
chemical vapor deposition |
| CVSD |
continuously variable slope delta [modulation] |
| cw |
carrier wave
composite wave
continuous wave |
| CX |
composite signaling |
| cxr |
carrier |
| D* |
specific detectivity |
| d |
deci (101) |
D( ) |
dispersion coefficient |
| da |
deka (10) |
| D-A |
digital-to-analog
digital-to-analog converter |
| D/L |
downlink |
| DACS |
digital access and cross-connect system |
| DAMA |
demand assignment multiple access |
| DARPA |
Defense Advanced Research Projects Agency [formerly ARPA] |
| dB |
decibel |
| dBa |
decibels adjusted |
| dBa(F1A) |
noise power measured by a set with F1A-line weighting |
| dBa(HA1) |
noise power measured by a set with HA1-receiver weighting |
| dBa0 |
noise power measured at zero transmission level point |
| dBc |
dB relative to carrier power |
| dBm |
dB referred to 1 milliwatt |
| dBm(psoph) |
noise power in dBm measured by a set with psophometric weighting |
| DBMS |
database management system |
| dBmV |
dB referred to 1 millivolt across 75 ohms |
| dBm0 |
noise power in dBm referred to or measured at 0TLP |
| dBm0p |
noise power in dBm0 measured by a psophometric or noise measuring set
having psophometric weighting |
| dBr |
power difference in dB between any point and a reference point |
| dBrn |
dB above reference noise |
| dBrnC |
noise power in dBrn measured by a set with C-message weighting |
| dBrnC0 |
noise power in dBrnC referred to or measured at 0TLP |
| dBrn(f1-f2) |
flat noise power in dBrn |
| dBrn(144-line) |
noise power in dBrn measured by a set with 144-line weighting |
| dBv |
dB relative to 1 V (volt) peak-to-peak |
| dBW |
dB referred to 1 W (watt) |
| dBx |
dB above reference coupling |
| dc |
direct current |
| DCA |
Defense Communications Agency (now DISA) |
| DCE |
data circuit-terminating equipment |
| DCL |
direct communications link |
| DCPSK |
differentially coherent phase-shift keying |
| DCS |
Defense Communications System |
| DCTN |
Defense Commercial Telecommunications Network |
| DCWV |
direct-current working volts |
| DDD |
direct distance dialing |
| DDN |
Defense Data Network |
| DDS |
digital data service |
| DEL |
delete character |
| demarc |
demarcation point |
| demux |
demultiplex
demultiplexer
demultiplexing |
| dequeue |
double-ended queue |
| DES |
Data Encryption Standard |
| detem |
detector/emitter |
| DFSK |
double-frequency shift keying |
| DIA |
Defense Intelligence Agency |
| DID |
direct inward dialing |
| DIN |
Deutsches Institut für Normung |
| DIP |
dual in-line package |
| DISA |
Defense Information Systems Agency {formerly DCA} |
| DISC |
disconnect command |
| DISN |
Defense Information System Network |
| DISNET |
Defense Integrated Secure Network |
| DLA |
Defense Logistic Agency |
| DLC |
digital loop carrier |
| DLE |
data link escape character |
| DM |
delta modulation |
| DMA |
Defense Mapping Agency
direct memory access |
| DME |
distance measuring equipment |
| DMS |
Defense Message System |
| DNA |
Defense Nuclear Agency |
| DNIC |
data network identification code |
| DNPA |
data numbering plan area |
| DNS |
Domain Name System |
| DO |
design objective |
| DoC |
Department of Commerce |
| DOD |
Department of Defense
direct outward dialing |
| DODD |
Department of Defense Directive |
| DODISS |
Department of Defense Index of Specifications and Standards |
| DOD-STD |
Department of Defense Standard |
| DOS |
Department of State |
| DPCM |
differential pulse-code modulation |
| DPSK |
differential phase-shift keying |
| DQDB |
distributed-queue dual-bus [network] |
| DRAM |
dynamic random access memory |
| DRSI |
destination station routing indicator |
| DS |
digital signal
direct support |
| DS0 |
digital signal 0 |
| DS1 |
digital signal 1 |
| DS1C |
digital signal 1C |
| DS2 |
digital signal 2 |
| DS3 |
digital signal 3 |
| DS4 |
digital signal 4 |
| DSA |
dial service assistance |
| DSB |
double-sideband [transmission]
Defense Science Board |
| DSB-RC |
double-sideband reduced carrier transmission |
| DSB-SC |
double-sideband suppressed-carrier transmission |
| DSC |
digital selective calling |
| DSCS |
Defense Satellite Communications System |
| DSE |
data switching exchange |
| DSI |
digital speech interpolation |
| DSL |
digital subscriber line |
| DSN |
Defense Switched Network |
| DSR |
data signaling rate |
| DSS |
direct station selection |
| DSSCS |
Defense Special Service Communications System |
| DSTE |
data subscriber terminal equipment |
| DSU |
data service unit |
| DTE |
data terminal equipment |
| DTMF |
dual-tone multifrequency [signaling] |
| DTG |
date-time group |
| DTN |
data transmission network |
| DTS |
Diplomatic Telecommunications Service |
| DTU |
data transfer unit
data tape unit
digital transmission unit
direct to user |
| DVL |
direct voice link |
| DX signaling |
direct current signaling
duplex signaling |
| E |
exa (1018) |
| E-MAIL, e-mail |
electronic mail |
| EAS |
extended area service |
| EBCDIC |
extended binary coded decimal interchange code |
| Eb/N0 |
signal energy per bit per hertz of thermal noise |
| EBO |
embedded base organization |
| EBS |
Emergency Broadcast System |
| EBX |
electronic branch exchange |
| EC |
Earth coverage
Earth curvature |
| ECC |
electronically controlled coupling
enhance call completion |
| ECCM |
electronic counter-countermeasures |
| ECM |
electronic countermeasures |
| EDC |
error detection and correction |
| EDI |
electronic data interchange |
| EDTV |
extended-definition television |
| EHF |
extremely high frequency |
| EIA |
Electronic Industries Association |
| eirp |
effective isotropically radiated power
equivalent isotopically radiated power |
| EIS |
Emergency Information System |
| el |
elevation |
| ELECTRO-OPTINT |
electro-optical intelligence |
| ELF |
extremely low frequency |
| ELINT |
electronics intelligence
electromagnetic intelligence |
| ELSEC |
electronics security |
| ELT |
emergency locator transmitter |
| EMC |
electromagnetic compatibility |
| EMCON |
emission control |
| EMD |
equilibrium mode distribution |
| EME |
electromagnetic environment |
| emf |
electromotive force |
| EMI |
electromagnetic interference
electromagnetic interference control |
| EMP |
electromagnetic pulse |
| EMR |
electromagnetic radiation |
| EMR hazards |
electromagnetic radiation hazards |
| e.m.r.p. |
effective monopole radiated power
equivalent monopole radiated power |
| EMS |
electronic message system |
| EMSEC |
emanations security |
| emu |
electromagnetic unit |
| EMV |
electromagnetic vulnerability |
| EMW |
electromagnetic warfare
electromagnetic wave |
| ENQ |
enquiry character |
| EO |
end office |
| E.O. |
Executive Order |
| EOD |
end of data |
| EOF |
end of file |
| EOL |
end of line |
| EOM |
end of message |
| EOP |
end of program
end output |
| EOS |
end-of-selection character |
| EOT |
end-of-transmission character
end of tape |
| EOW |
engineering orderwire |
| EPROM |
erasable programmable read-only memory |
| EPSCS |
enhanced private switched communications system |
| ERL |
echo return loss |
| ERLINK |
emergency response link |
| ERP, e.r.p. |
effective radiated power |
| ES |
end system
expert system |
| ESC |
escape character
enhanced satellite capability |
| ESF |
extended superframe |
| ESM |
electronic warfare support measures |
| ESP |
enhanced service provider |
| ESS |
electronic switching system |
| ETB |
end-of-transmission-block character |
| ETX |
end-of-text character |
| EW |
electronic warfare |
| EXCSA |
Exchange Carriers Standards Association |
| f |
femto (10-15) |
| f |
frequency |
| FAA |
Federal Aviation Administration |
| FAQ file |
Frequently Asked Questions file |
| FAX |
facsimile |
| FC |
functional component |
| FCC |
Federal Communications Commission |
| FCS |
frame check sequence |
| FDDI |
fiber distributed data interface |
| FDDI-2 |
fiber distributed data interface-2 |
| FDHM |
full duration at half maximum |
| FDM |
frequency-division multiplexing |
| FDMA |
frequency-division multiple access |
| FDX |
full duplex |
| FEC |
forward error correction |
| FECC |
Federal Emergency Communications Coordinators |
| FED-STD |
Federal Standard |
| FEMA |
Federal Emergency Management Agency |
| FEP |
front-end processor |
| FET |
field effect transistor |
| FIFO |
first-in first-out |
| FIP |
Federal Information Processing |
| FIPS |
Federal Information Processing Standards |
| FIR |
finite impulse response |
| FIRMR |
Federal Information Resources Management Regulations |
| FISINT |
foreign instrumentation signals intelligence |
| FLTSATCOM |
Fleet Satellite Communications |
| flops |
floating-point operations per second |
| FM |
frequency modulation |
| FO |
fiber optics |
| FOC |
final operational capability
full operational capability |
| FOT |
frequency of optimum traffic
frequency of optimum transmission |
| FPIS |
forward propagation ionospheric scatter |
| ft/min |
feet per minute |
| fps |
foot-pound-second |
| FPS |
frames per second
focus projection and scanning |
| FRP |
Federal Response Plan |
| FSDPSK |
filtered symmetric differential phase-shift keying |
| FSK |
frequency-shift keying |
| FSS |
fully separate subsidiary |
| FSTS |
Federal Secure Telephone Service {no longer in operation} |
| FT |
fiber optic T-carrier |
| FTAM |
file transfer, access, and management |
| FTF |
Federal Telecommunications Fund |
| ft/s |
feet per second |
| FTS |
Federal Telecommunications System |
| FTS2000 |
Federal Telecommunications System 2000 |
| FTSC |
Federal Telecommunications Standards Committee |
| FTP |
file transfer protocol |
| FWHM |
full width at half maximum |
| FX |
fixed service
foreign exchange service |
| FYDP |
Five Year Defense Plan |
| g |
profile parameter |
| G |
giga (109) |
| GBH |
group busy hour |
| GCT |
Greenwich Civil Time |
| GDF |
group distribution frame |
| GETS |
Government Emergency Telecommunications Service |
| GFE |
Government-furnished equipment |
| GGCL |
government-to-government communications link |
| GHz |
gigahertz |
| GII |
Global Information Infrastructure |
| GMT |
Greenwich Mean Time |
| GOS |
grade of service |
| GOSIP |
Government Open Systems Interconnection Profile |
| GSA |
General Services Administration |
| GSTN |
general switched telephone network |
| G/T |
antenna gain-to-noise-temperature |
| GTP |
Government Telecommunications Program |
| GTS |
Government Telecommunications System |
| GUI |
graphical user interface |
| h |
hecto (102)
hour
Planck's constant |
| HCS |
hard clad silica [fiber] |
| HDLC |
high-level data link control |
| HDTV |
high-definition television |
| HDX |
half-duplex [operation] |
| HE11mode |
the fundamental hybrid mode [of an optical fiber] |
| HEMP |
high-altitude electromagnetic pulse |
| HERF |
hazards of electromagnetic radiation to fuel |
| HERO |
hazards of electromagnetic radiation to ordnance |
| HERP |
hazards of electromagnetic radiation to personnel |
| HF |
high frequency |
| HFDF |
high-frequency distribution frame |
| HLL |
high-level language |
| HPC |
high probability of completion |
| HV |
high voltage |
| Hz |
hertz |
| IA |
International Alphabet [CCITT] |
| I&C |
installation and checkout |
| IC |
integrated circuit |
| ICI |
incoming call identification |
| ICNI |
Integrated Communications, Navigation, and Identification |
| ICW |
interrupted continuous wave |
| IDDD |
International Direct Distance Dialing |
| IDF |
intermediate distribution frame |
| IDN |
integrated digital network |
| IDTV |
improved-definition television |
| IEC |
International Electrotechnical Commission |
| IEEE |
Institute of Electrical and Electronics Engineers |
| IES |
Industry Executive Subcommittee |
| IF |
intermediate frequency |
| I/F |
interface |
| IFF |
identification, friend or foe |
| IFRB |
International Frequency Registration Board (now Radio Regulations
Board ) |
| IFS |
ionospheric forward scatter |
| IIR |
infinite impulse response |
| IITF |
Information Infrastructure Task Force |
| ILD |
injection laser diode |
| ILS |
instrument landing system |
| IM |
intensity modulation
intermodulation |
| IMA |
individual mobilization augmentee |
| I&M |
installation and maintenance |
| IMD |
intermodulation distortion |
| IMP |
interface message processor |
| IN |
intelligent network |
| IN/1, IN/1+, IN/2 |
intelligent network concepts |
| INFOSEC |
information systems security |
| INS |
inertial navigation system |
| INTELSAT |
International Telecommunications Satellite Consortium |
| INWATS |
Inward Wide-Area Telephone Service |
| I/O |
input/output [device] |
| IOC |
integrated optical circuit
initial operational capability
input-output controller |
| IP |
Internet protocol
intelligent peripheral |
| IPA |
intermediate power amplifier |
| IPC |
information processing center |
| IPM |
impulses per minute
interference prediction model
internal polarization modulation
interruptions per minute |
| in/s |
inches per second |
| ips |
interruptions per second |
| IPX |
Internet Packet Exchange |
| IQF |
intrinsic quality factor |
| IR |
infrared |
| IRAC |
Interdepartment Radio Advisory Committee |
| IRC |
international record carrier
Interagency Radio Committee |
| ISB |
independent-sideband [transmission] |
| ISDN |
Integrated Services Digital Network |
| ISM |
industrial, scientific, and medical (applications) |
| ISO |
International Organization for Standardization |
| ITA |
International Telegraph Alphabet |
| ITA-5 |
International Telegraph Alphabet Number 5 |
| ITC |
International Teletraffic Congress |
| ITS |
Institute for Telecommunication Sciences |
| ITSO |
International Telecommunications Satellite Organization |
| ITU |
International Telecommunication Union |
| IVDT |
integrated voice data terminal |
| IXC |
interexchange carrier |
| JANAP |
Joint Army-Navy-Air Force Publication(s) |
| JCS |
Joint Chiefs of Staff |
| JPL |
Jet Propulsion Laboratory |
| JSC |
Joint Steering Committee [now JTSSG]
Joint Spectrum Center |
| JTC3A |
Joint Tactical Command, Control and Communications Agency |
| JTIDS |
Joint Tactical Information Distribution System |
| JTRB |
Joint Telecommunications Resources Board |
| JTSSG |
Joint Telecommunications Standards Steering Group [formerly JSC] |
| JWID |
Joint Warrior Interoperability Demonstration |
| k |
kilo (103)
Boltzmann's constant |
| K |
coefficient of absorption
kelvin |
|
| KDC |
key distribution center |
| KDR |
keyboard data recorder |
| KDT |
keyboard display terminal |
| kg |
kilogram |
| kg•m•s |
kilogram-meter-second |
| kHz |
kilohertz |
| km |
kilometer |
| k , k |
kilohm |
| KSR |
keyboard send/receive device |
| kT |
noise power density |
| KTS |
key telephone system |
| KTU |
key telephone unit |
|
wavelength |
| CO |
cutoff wavelength |
| LAN |
local area network |
| LANTFLT |
Atlantic Fleet |
| LAP-B |
Data Link Layer protocol [CCITT Recommendation X.25 (1989)] |
| LAP-D |
link access procedure D |
| laser |
light amplification by stimulated emission of radiation |
| LASINT |
laser intelligence |
| LATA |
local access and transport area |
| LBO |
line buildout |
| LC |
limited capability |
| LCD |
liquid crystal display |
| LD |
long distance |
| LDM |
limited distance modem |
| LEC |
local exchange carrier |
| LED |
light-emitting diode |
| LF |
low frequency |
| LFB |
look-ahead-for-busy [information] |
| LIFO |
last-in first-out |
| LLC |
logical link control [sublayer] |
| l/m |
lines per minute |
| LMF |
language media format |
| LMR |
land mobile radio |
| LNA |
launch numerical aperture |
| LOF |
lowest operating frequency |
| loran |
long-range aid to navigation system
long-range radio navigation
long-range radio aid to navigation system |
| LOS |
line of sight
loss of signal |
| LP |
linearly polarized [mode]
linear programming
linking protection
log-periodic [antenna]
log-periodic [array] |
| LPA |
linear power amplifier |
| LPC |
linear predictive coding |
| LPD |
low probability of detection |
| LPI |
low probability of interception |
| lpi |
lines per inch |
| lpm |
lines per minute |
| LP01 |
the fundamental mode (of an optical fiber) |
| LQA |
link quality analysis |
| LRC |
longitudinal redundancy check |
| LSB |
lower sideband, least significant bit |
| LSI |
large scale integrated [circuit]
large scale integration
line status indication |
| LTC |
line traffic coordinator |
| LUF |
lowest usable high frequency |
| LULT |
line-unit-line termination |
| LUNT |
line-unit-network termination |
| LV |
low voltage |
| m |
meter
milli (10-3) |
| M |
mega (106) |
| MAC |
medium access control [sublayer] |
| MACOM |
major command |
| MAN |
metropolitan area network |
| MAP |
manufacturers' automation protocol |
| maser |
microwave amplification by the stimulated emission of radiation |
| M[] |
material dispersion coefficient |
| MAU |
medium access unit |
| MCC |
maintenance control circuit |
| MCEB |
Military Communications-Electronics Board |
| MCM |
multicarrier modulation |
| MCS |
Master Control System |
| MCW |
modulated continuous wave |
| MCXO |
microcomputer compensated crystal oscillator |
| MDF |
main distribution frame |
| MDT |
mean downtime |
| MEECN |
Minimum Essential Emergency Communications Network |
| MERCAST |
merchant-ship broadcast system |
| MF |
medium frequency
multifrequency [signaling] |
| MFD |
mode field diameter |
| MFJ |
Modification of Final Judgment |
| MFSK |
multiple frequency-shift keying |
| MHF |
medium high frequency |
| MHS |
message handling service
message handling system |
| MHz |
megahertz |
| mi |
mile |
| MIC |
medium interface connector
microphone
microwave integrated circuit
minimum ignition current
monolithic integrated circuit
mutual interface chart |
| MILNET |
military network |
| MIL-STD |
Military Standard |
| min |
minute |
| MIP |
medium interface point |
| MIPS, mips |
million instructions per second |
| MIS |
management information system |
| MKS |
meter-kilogram-second |
| MLPP |
multilevel precedence and preemption |
| MMW |
millimeter wave |
| modem |
modulator-demodulator |
| modified AMI code |
modified alternate mark inversion code |
| mol |
mole |
| ms |
millisecond (10-3second) |
| MSB |
most significant bit |
| MSK |
minimum-shift keying |
| MTBF |
mean time between failures |
| MTBM |
mean time between maintenance |
| MTBO |
mean time between outages |
| MTBPM |
mean time between preventive maintenance |
| MTF |
modulation transfer function |
| MTSO |
mobile telephone switching office |
| MTSR |
mean time to service restoral |
| MTTR |
mean time to repair |
 |
micro (10-6) |
| s |
microsecond |
| MUF |
maximum usable frequency |
| muldem |
multiplexer/demultiplexer |
| MUX |
multiplex
multiplexer |
| MUXing |
multiplexing |
| mw |
microwave |
| MWI |
message waiting indicator |
| MWV |
maximum working voltage |
| n |
nano (10-9)
refractive index |
| N0 |
sea level refractivity
spectral noise density |
| NA |
numerical aperture |
| NACSEM |
National Communications Security Emanation Memorandum |
| NACSIM |
National Communications Security Information Memorandum |
| NAK |
negative-acknowledge character |
| NASA |
National Aeronautics and Space Administration |
| NATA |
North American Telecommunications Association |
| NATO |
North Atlantic Treaty Organization |
| NAVSTAR-GPS |
Navigational Satellite Timing and Ranging--Global Positioning System |
| NBFM |
narrowband frequency modulation |
| NBH |
network busy hour |
| NBRVF |
narrowband radio voice frequency |
| NBS |
National Bureau of Standards [now NIST] |
| NBSV |
narrowband secure voice |
| NCA |
National Command Authorities |
| NCC |
National Coordinating Center for Telecommunications |
| NCS |
National Communications System
net control station |
| NCSC |
National Communications Security Committee |
| NDCS |
network data control system |
| NDER |
National Defense Executive Reserve |
| NEACP |
National Emergency Airborne Command Post |
| NEC |
National Electric Code ® |
| NEP |
noise equivalent power |
| NES |
noise equivalent signal |
| NF |
noise figure |
| NFS |
Network File System |
| NIC |
network interface card |
| NICS |
NATO Integrated Communications System |
| NID |
network interface device
network inward dialing
network information database |
| NII |
National Information Infrastructure |
| NIOD |
network inward/outward dialing |
| NIST |
National Institute of Standards and Technology [formerly NBS] |
| NIU |
network interface unit |
| NLP |
National Level Program |
| nm |
nanometer |
| NMCS |
National Military Command System |
| nmi |
nautical mile |
| NOD |
network outward dialing |
| Np |
neper |
| NPA |
numbering plan area |
| NPR |
noise power ratio |
| NRI |
net radio interface |
| NRM |
network resource manager |
| NRRC |
Nuclear Risk Reduction Center |
| NRZ |
non-return-to-zero |
| NRZI |
non-return-to-zero inverted |
| NRZ-M |
non-return-to-zero mark |
| NRZ-S |
non-return-to-zero space |
| NRZ1 |
non-return-to-zero, change on ones |
| NRZ-1 |
non-return-to-zero mark |
| ns |
nanosecond |
| NSA |
National Security Agency |
| NSC |
National Security Council |
| NS/EP telecommunications |
National Security or Emergency Preparedness telecommunications |
| NSTAC |
National Security Telecommunications Advisory Committee |
| NTCN |
National Telecommunications Coordinating Network |
| NTDS |
Naval Tactical Data System |
| NTMS |
National Telecommunications Management Structure |
| NT1 |
Network termination 1 |
| NT2 |
Network termination 2 |
| NTI |
network terminating interface |
| NTIA |
National Telecommunications and Information Administration |
| NTN |
network terminal number |
| NTSC |
National Television Standards Committee
National Television Standards Committee [standard] |
| NUL |
null character |
| NVIS |
near-vertical-incidence skywave |
 |
ohm |
| O&M |
operations and maintenance |
| OC |
operations center |
| OCC |
other common carrier |
| OCR |
optical character reader
optical character recognition |
| OCU |
orderwire control unit |
| OCVCXO |
oven controlled-voltage controlled crystal oscillator |
| OCXO |
oven controlled crystal oscillator |
| OD |
optical density
outside diameter |
| OFC |
optical fiber, conductive |
| OFCP |
optical fiber, conductive, plenum |
| OFCR |
optical fiber, conductive, riser |
| OFN |
optical fiber, nonconductive |
| OFNP |
optical fiber, nonconductive, plenum |
| OFNR |
optical fiber, nonconductive, riser |
| OMB |
Office of Management and Budget |
| ONA |
open network architecture |
| opm |
operations per minute |
| OPMODEL |
operations model |
| OPSEC |
operations security |
| OPX |
off-premises extension |
| OR |
off-route service
off-route aeronautical mobile service |
| OSHA |
Occupational Safety and Health Administration |
| OSI |
open switching interval
Open Systems Interconnection |
| OSI-RM |
Open Systems Interconnection--Reference Model |
| OSRI |
originating stations routing indicator |
| OSSN |
originating stations serial number |
| OTAM |
over-the-air management of automated HF network nodes |
| OTAR |
over-the-air rekeying |
| OTDR |
optical time domain reflectometer
optical time domain reflectometry |
| OW |
orderwire [circuit] |
| p |
pico (10-12) |
| P |
peta (1015) |
| PABX |
private automatic branch exchange |
| PAD |
packet assembler/disassembler |
| PAL |
phase alternation by line |
| PAL-M |
phase alternation by line--modified |
| PAM |
pulse-amplitude modulation |
| PAMA |
pulse-address multiple access |
| p/a r |
peak-to-average ratio |
| PAR |
performance analysis and review |
| PARAMP |
parametric amplifier |
| par meter |
peak-to-average ratio meter |
| PAX |
private automatic exchange |
| PBER |
pseudo-bit-error-ratio |
| PBX |
private branch exchange |
| PC |
carrier power (of a radio transmitter)
personal computer |
| PCB |
power circuit breaker
printed circuit board |
| PCM |
pulse-code modulation
plug compatible module
process control module |
| PCS |
Personal Communications Services
personal communications system
plastic-clad silica [fiber] |
| PCSR |
parallel channels signaling rate |
| PD |
photodetector |
| PDM |
pulse delta modulation
pulse-duration modulation |
| PDN |
public data network |
| PDS |
protected distribution system
power distribution system
program data source |
| PDT |
programmable data terminal |
| PDU |
protocol data unit |
| PE |
phase-encoded [recording] |
| PEP |
peak envelope power (of a radio transmitter) |
| pF |
picofarad |
| PF |
power factor |
| PFM |
pulse-frequency modulation |
| PI |
protection interval |
| PIC |
plastic insulated cable |
| ping |
packet Internet groper |
| PIV |
peak inverse voltage |
| PLA |
programmable logic array |
| PLL |
phase-locked loop |
| PLN |
private line network |
| PL/I |
programming language 1 |
| PLR |
pulse link repeater |
| PLS |
physical signaling sublayer |
| pm |
phase modulation |
| PM |
mean power
polarization-maintaining [optical fiber]
preventive maintenance
pulse modulation |
| PMB |
pilot-make-busy [circuit] |
| PMO |
program management office |
| POI |
point of interface |
| POP |
point of presence |
| POSIX |
portable operating system interface for computer environments |
| POTS |
plain old telephone service |
| PP |
polarization-preserving [optical fiber] |
| P-P |
peak-to-peak [value] |
| P/P |
point-to-point |
| PPM |
pulse-position modulation |
| pps |
pulses per second |
| PR |
pulse rate |
| PRF |
pulse-repetition frequency |
| PRI |
primary rate interface |
| PRM |
pulse-rate modulation |
| PROM |
programmable read-only memory |
| PRR |
pulse repetition rate |
| PRSL |
primary area switch locator |
| PS |
permanent signal |
| psi |
pounds [force] per square inch |
| PSK |
phase-shift keying |
| PSN |
public switched network |
| p-static |
precipitation static |
| PSTN |
public switched telephone network |
| PTF |
patch and test facility |
| PTM |
pulse-time modulation |
| PTT |
postal, telephone, and telegraph
push-to-talk [operation] |
| PTTC |
paper tape transmission code |
| PTTI |
precise time and time interval |
| PU |
power unit |
| PUC |
public utility commission
public utilities commission |
| PVC |
permanent virtual circuit
polyvinyl chloride [insulation] |
| pW |
picowatt |
| PWM |
pulse-width modulation [deprecated] |
| pWp |
picowatt, psophometrically weighted |
| pWp0 |
picowatts, relative to a 0TLP |
| pX |
peak envelope power (in dB) |
| PX |
peak envelope power
private exchange
peak envelope power (in watts) |
| pY |
mean power [in dB] |
| PY |
mean power [in watts] |
| pZ |
carrier power [in dB] |
| PZ |
carrier power [in watts] |
| QA |
quality assurance |
| QAM |
quadrature amplitude modulation |
| QC |
quality control |
| QCIF |
quarter common intermediate format |
| QMR |
qualitative material requirement |
| QOS |
quality of service |
| QPSK |
quadrature phase-shift keying |
| QRC |
quick reaction capability |
| QSTAG |
Quadripartite Standardization Agreement |
| R |
route service |
| racon |
radar beacon |
| rad |
radian
radiation absorbed dose |
| radar |
radio detection and ranging |
| RADHAZ |
electromagnetic radiation hazards |
| RADINT |
radar intelligence |
| RAM |
random access memory
reliability, availability, and maintainability |
| R&D |
research and development |
| RATT |
radio teletypewriter system |
| RBOC |
Regional Bell Operating Company |
| RbXO |
rubidium-crystal oscillator |
| RC |
reflection coefficient
resource controller |
| RCC |
radio common carrier |
| RCVR |
receiver |
| RDF |
radio direction-finding |
| REA |
Rural Electrification Administration |
| REN |
ringer equivalency number |
| RGB |
red-green-blue |
| rf |
radio frequency
range finder |
| RFI |
radio frequency interference |
| RFP |
request for proposal |
| RFQ |
request for quotation |
| RH |
relative humidity |
| RHR |
radio horizon range |
| RI |
routing indicator |
| RISC |
reduced instruction set chip |
| RJ |
registered jack |
| RJE |
remote job entry |
| rms |
root-mean-square [deviation] |
| RO |
read only
receive only |
| ROA |
recognized operating agency |
| ROC |
required operational capability |
| ROM |
read-only memory |
| ROSE |
remote operations service element protocol |
| rpm |
revolutions per minute |
| RPM |
rate per minute |
| rps |
revolutions per second |
| RQ |
repeat-request |
| RR |
repetition rate |
| RSL |
received signal level |
| rss |
root-sum-square |
| R/T |
real time |
| RTA |
remote trunk arrangement |
| RTS |
request to send |
| RTTY |
radio teletypewriter |
| RTU |
remote terminal unit |
| RTX |
request to transmit |
| RVA |
reactive volt-ampere |
| RVWG |
Reliability and Vulnerability Working Group |
| RWI |
radio and wire integration |
| RX |
receive
receiver |
| RZ |
return-to-zero |
| s |
second |
| SCC |
specialized common carrier |
| SCE |
service creation environment |
| SCF |
service control facility |
| SCP |
service control point |
| SCPC |
single channel per carrier |
| SCR |
semiconductor-controlled rectifier
silicon-controlled rectifier |
| SCSR |
single channel signaling rate |
| SDLC |
synchronous data link control |
| SDM |
space-division multiplexing [deprecated] |
| SDN |
software-defined network |
| SECAM |
systeme electronique couleur avec memoire |
| SECDEF |
Secretary of Defense |
| SECORD |
secure voice cord board |
| SECTEL |
secure telephone |
| SETAMS |
systems engineering, technical assistance, and management services |
| SEVAS |
Secure Voice Access System |
| S-F |
store-and-forward |
| SF |
single-frequency [signaling] |
| SGDF |
supergroup distribution frame |
| S/H |
sample and hold |
| SHA |
sidereal hour angle |
| SHARES |
Shared Resources (SHARES) HF Radio Program |
| SHF |
super high frequency |
| SI |
International System of Units |
| SID |
sudden ionospheric disturbance |
| SIGINT |
signals intelligence |
| SINAD |
signal-plus-noise-plus-distortion to noise-plus-distortion ratio |
| S() |
chromatic dispersion slope |
| SLD |
superluminescent diode [see superluminescent LED ] |
| SLI |
service logic interpreter |
| SLP |
service logic program |
| SMDR |
station message-detail recording |
| SMSA |
standard metropolitan statistical area |
| SNR |
signal-to-noise ratio |
| SOH |
start-of-heading character |
| SOM |
start of message |
| sonar |
sound navigation and ranging |
| SONET |
synchronous optical network |
| SOP |
standard operating procedure |
| SOR |
start of record |
| SOW |
statement of work |
| (S+N)/N |
signal-plus-noise-to-noise ratio |
| sr |
steradian |
| S/R |
send and receive |
| SSB |
single-sideband [transmission] |
| SSB-SC |
single-sideband suppressed carrier [transmission] |
| SSN |
station serial number |
| SSP |
service switching point |
| SSUPS |
solid-state uninterruptible power system |
| STALO |
stabilized local oscillator |
| STANAG |
Standardization Agreement [NATO] |
| STD |
subscriber trunk dialing |
| STFS |
standard time and frequency signal [service]
standard time and frequency service |
| STL |
standard telegraph level
studio-to-transmitter link |
| STP |
standard temperature and pressure
signal transfer point |
| STU |
secure telephone unit |
| STX |
start-of-text character |
| SUB |
substitute character |
| SWR |
standing wave ratio |
| SX |
simplex signaling |
| SXS |
step-by-step switching system |
| SYN |
synchronous idle character |
| SYSGEN |
system generation |
| T |
tera (1012) |
| TADIL |
tactical data information link |
| TADIL-A |
tactical data information link-A |
| TADIL-B |
tactical data information link-B |
| TADS |
teletypewriter automatic dispatch system |
| TADSS |
Tactical Automatic Digital Switching System |
| TAI |
International Atomic Time |
| TASI |
time-assignment speech interpolation |
| TAT |
trans-Atlantic telecommunication (cable) |
| TC |
toll center |
| TCB |
trusted computing base |
| TCC |
telecommunications center |
| TCCF |
Tactical Communications Control Facility |
| TCF |
technical control facility |
| TCP |
transmission control protocol |
| TCS |
trusted computer system |
| TCU |
teletypewriter control unit |
| TCVXO |
temperature compensated-voltage controlled crystal oscillator |
| TCXO |
temperature controlled crystal oscillator |
| TD |
time delay
transmitter distributor |
| TDD |
Telecommunications Device for the Deaf |
| TDM |
time-division multiplexing |
| TDMA |
time-division multiple access |
| TE |
transverse electric [mode] |
| TED |
trunk encryption device |
| TEK |
traffic encryption key |
| TEM |
transverse electric and magnetic [mode] |
| TEMPEST |
compromising emanations |
| TEMS |
telecommunications management system |
| TGM |
trunk group multiplexer |
| THD |
total harmonic distortion |
| THF |
tremendously high frequency |
| THz |
terahertz |
| TIA |
Telecommunications Industry Association |
| TIE |
time interval error |
| TIFF |
tag image file format |
| TIP |
terminal interface processor |
| TK |
response timer |
| TLP |
transmission level point |
| TM |
transverse magnetic [mode] |
| TP |
toll point |
| TRANSEC |
transmission security |
| TRC |
transverse redundancy check |
| TRF |
tuned radio frequency |
| TRI-TAC |
tri-services tactical [equipment] |
| TSK |
transmission security key |
| TSP |
Telecommunications Service Priority [system] |
| TSPS |
traffic service position system |
| TSR |
telecommunications service request
terminate and stay resident |
| TTL |
transistor-transistor logic |
| TTTN |
tandem tie trunk network |
| TTY |
teletypewriter |
| TTY/TDD |
Telecommunications Device for the Deaf |
| TV |
television |
| TW |
traveling wave |
| TWT |
traveling wave tube |
| TWTA |
traveling wave tube amplifier |
| TWX® |
teletypewriter exchange service |
| TX |
transmit
transmitter |
| UDP |
User Datagram Protocol |
| UHF |
ultra high frequency |
| ULF |
ultra low frequency |
| U/L |
uplink |
| UPS |
uninterruptible power supply |
| UPT |
Universal Personal Telecommunications [service] |
| USB |
upper sideband |
| USDA |
U.S. Department of Agriculture |
| USFJ |
U.S. Forces, Japan |
| USFK |
U.S. Forces, Korea |
| USNO |
U.S. Naval observatory |
| USTA |
U.S. Telephone Association |
| UT |
Universal Time |
| UTC |
Coordinated Universal Time |
| uv |
ultraviolet |
| V |
volt
normalized frequency |
| VA |
value-added [network service]
volt-ampere |
| VAN |
value-added network |
| VAR |
value added reseller |
| VARISTAR |
variable resistor |
| vars |
volt-amperes reactive |
| VC |
virtual circuit |
| VCO |
voltage-controlled oscillator |
| VCXO |
voltage-controlled crystal oscillator |
| V/D |
voice/data |
| Vdc |
volts direct current |
| VDU |
video display unit
visual display unit |
| VF |
voice frequency |
| VFCT |
voice frequency carrier telegraph |
| VFCTG |
voice frequency carrier telegraph |
| VFDF |
voice frequency distribution frame |
| VFO |
variable-frequency oscillator |
| VFTG |
voice-frequency telegraph |
| VHF |
very high frequency |
| VLF |
very low frequency |
| V/m |
volts per meter |
| VNL |
via net loss |
| VNLF |
via net loss factor |
| vocoder |
voice-coder |
| vodas |
voice-operated device anti-sing |
| vogad |
voice-operated gain-adjusting device |
| volcas |
voice-operated loss control and echo/signaling suppression |
| vox |
voice-operated relay circuit
voice operated transmit |
| VRC |
vertical redundancy check |
| VSAT |
very small aperture terminal |
| VSB |
vestigial sideband [transmission] |
| VSM |
vestigial sideband modulation |
| VSWR |
voltage standing wave ratio |
| VT |
virtual terminal |
| VTU |
video teleconferencing unit |
| vu |
volume unit |
| WADS |
wide area data service |
| WAIS |
Wide Area Information Servers |
| WAN |
wide area network |
| WARC |
World Administrative Radio Conference |
| WATS |
Wide Area Telecommunications Service
Wide Area Telephone Service |
| WAWS |
Washington Area Wideband System |
| WDM |
wavelength-division multiplexing |
| WHSR |
White House Situation Room |
| WIN |
WWMCCS Intercomputer Network |
| WITS |
Washington Integrated Telecommunications System |
| WORM |
write once, read many times |
| wpm |
words per minute |
| wps |
words per second |
| WRU |
who-are-you [character] |
| wv |
working voltage |
| WVDC |
working voltage direct current |
| WWDSA |
worldwide digital system architecture |
| WWMCCS |
Worldwide Military Command and Control System |
| WWW |
World Wide Web |
| XMIT |
transmit |
| XMSN |
transmission |
| XMTD |
transmitted |
| XMTR |
transmitter |
| XO |
crystal oscillator |
| XOFF |
transmitter off |
| XON |
transmitter on |
| XT |
crosstalk |
| XTAL |
crystal |
| Z |
Zulu time |
| ZD |
zero defects |
| Zo |
characteristic impedance |
| 0TLP |
zero transmission level point |