Always under construction By Hugh Stegman nv6H

IONCAP IONospheric Communications Analysis and Prediction, original

prediction algorithm, still used

IOR Indian Ocean Region

IOS Indian Ocean Station (NASA)

IP Internet Protocol

IPA Intermediate power amplifier

IPB Intelligence Preparation of the Battlefield

IPBO Input Power BackOff

IPC Institute for Interconnecting and Packaging Electronic Circuits

IPCP Internet Protocol Control Protocol

IPF Intelligence Processing Facility

IPI Intelligent Peripheral Interface

IPIR Initial Photo Interpretation Report

IPIX Interface Processor for Imagery Exchange

IPL Image Product Library

IPng IP next generation

IPS (1) Inches per second

(2) Ionospheric Prediction Service (Australia, original name for space

weather agcy)

(3) Integrated Power Systems

IPSec Internet Protocol Security

IPSS International Packet SwitchStream, now GNS (UK)

IPT Integrated Program Team

IPTV Television via IP protocol (Internet TV)

IPX Internetwork Packet Exchange (Novell)

IQ In-phase/Quadrature

IQSY International Year of the Quiet Sun, 1960's research interval

IR (1) Infrared

(2) Instrument route (numbered military training route)

IRA (1) International Reference Alphabet

(2) Impulse Radiating Antennas

IRAC Interdepartment Radio Advisory Committee (part of US NTIA)

IRBM Intermediate Range Ballistic Missile

IRC (1) International Reply Coupon

(2) Internet Relay Chat, world's primo time waster

(3) International Red Cross

(4) Incrementally Related Carrier (CATV channel scheme)

(5) International Record Carrier

IRCA International Radio Club of America

IRCCM Infrared Counter-Countermeasures

IRCM Infrared Countermeasures

IRE Institute of Radio Engineers, now IEEE

IRI Ionospheric Research Instrument, transmitter part of HAARP

IRINT Infrared intelligence

IRIS Improved Radio Ionospheric Sounder

IRL Ireland (country code)

IRN Iran (country code)

IRNSS Indian Regional Navigational Satellite System

IRQ (1) Interrupt request (computer hardware)

(2) Iraq (country code)

IRRM Image Recording Request Message

IRRS Italian Radio Relay Service

IRS (1) Information Receiving Station (SITOR)

(2) Internal Revenue Service (US)

(3) Infernal Revenue Service (U$)

IRSS Infrared Surveillance System

IRST Infrared Search and Track

IS (1) Interval signal

(2) Intermediate Standard, formerly RS

(3) Information System

(4) Islamic State; name taken by terrorist group

IS-95 North American cellular standard

IS-136 ANSI-136 multiple access standard

ISA (1) Industry Standard Architecture (PC-AT bus)

(2) In-Session Activation (telco)

ISABPS Integrated Submarine Automated Broadcast Processor System

ISAM Indexed Sequential Access Method

ISAR Inverse Synthetic Aperture Radar

ISARC Intelligence, Surveillance, and Reconnaissance Cell

ISB (1) Independent Sideband

(2) Intermediate Staging Base

ISC Initial Scope Command (phase I)

ISD Inverted Scanning Direction (radiofax)

ISDB Integrated Services Digital Broadcasting (Japanese digital TV/Radio)

ISDL ISDN Digital Subscriber Line

ISDN (1) Integrated Services & Data Network (telco)

(2) Integrated Services Digital Network

ISEC Information Systems Engineering Command

ISF International Science Foundation

ISI Inter-Symbol Interference

ISIL Islamic State of Iraq and the Levant

ISIS Islamic State of Iraq and Syria

ISM Industrial, Scientific, Medical (RF devices)

ISMLS Interim Standard Microwave Landing System

ISO (1) International Standards Organization

(2) International Organisation for Standardisation

(3) International Organizations for Standardization

ISODE ISO Development Environment

ISP Internet service provider

ISR In-System Reprogrammable

ISS (1) Information Sending Station (SITOR)

(2) International Space Station

ISSO (1) Information System Security Officer

(2) Information Systems Security Organization (US)

ISTR I Seem To Recall

iSWA Integrated Space Weather Analysis system (NASA)

IT (1) Information Technology

(2) Information Technology Directorate (FEMA)

ITA International Telegraph Alphabet

ITA1 International Telegraph Alphabet #1 (Old cablegrams, obsolete)

ITA2 International Telegraph Alphabet #2 (Baudot double-shift)

ITA3 International Telegraph Alphabet #3 (7-bit ARQ)

ITA4 International Telegraph Alphabet #4 (FM VFT)

ITER Improved Triple Ejector Rack

ITFS Instructional Television Fixed Service

ITO Installation transportation office

ITS (1) Institute for Telecommunication Sciences

(2) Intelligent Transportation Systems

ITU International Telecommunications Union

ITU-R ITU Sector for Radiocommunications, old CCIR

ITU-R M.493-6 Protocol for maritime Digital Selective Calling

ITU-T International Telecommunications Union - Telecommunication

Standardization Sector

ITU-T ITU Sector for Telecommunications, old CCITT

ITU-TSS ITU Telecommunications Standards Section, old CCITT

ITWS Integrated Terminal Weather System

IUGG International Union of Geodesy and Geophysics

IUSS Integrated Undersea Surveillance System

IUWDS International Ursigram and World Days Service

IVAS Inward Voice Activated Services (telco)

IVCS Integrated Voice Communication Systems

IVTT Integrated VERDIN Transmit Terminal

IW Information Warfare

IWG Interoperability Working Group (SHARES)

IWS Information Warfare Squadron

IWTS Integrated Terminal Weather System

IXS Information Exchange System

j Vector

J/S Jamming to signal ratio

J2 Intelligence directorate at a joint headquarters

J2B Single sideband, suppressed carrier tone teleprinting (emission)

J3E Single sideband, suppressed carrier AM radiotelephony (emission)

J4 Logistics directorate at a joint headquarters

JAA Joint Aviation Authorities (Europe)

JAFO Just Another F[ine] Observer

JAG Judge Advocate General

JALBTCX Joint Airborne Lidar Bathymetry Technical Center of Expertise

JAN Joint Army/Navy (spec)

JANA Jamahiriyah News Agency

JANET Joint Academic NETwork (UK)

JAR Joint Aviation Requirements (Europe)

JARL Japan Amateur Radio League

JARS Joint Air Reserve Station

JASORS Joint Advanced Special Operations Radio System

JATACS Joint Advanced Tactical Command and Control System

JATCC Joint Air Traffic Control Center

JAWS Juneau Airport Wind System

JAWSAT Joint Air Force-Weber State University Satellite

JCIS Joint Communications and Information System

JCS Joint Chiefs of Staff

JCSE Joint Communications Support Element

JDC Japanese Digital Cellular

JDF Japanese Defense Force

JDISS Joint Deployable Intelligence Support System

JEDEC Joint Electronic Device Engineering Council

Jeep Believed from "General Purpose" military vehicle, now a tradename

JFA Japan Fisheries Association

JFC Joint force commander

JFET Junction (gate) Field-Effect Transistor

JIATF-E Joint Interagency Task Force, East (incorporates JTF-4)

JIATF-S Joint Interagency Task Force, South (inc. JTF-6)

JIATF-W Joint Interagency Task Force, West (inc. JTF-5)

JIC Joint Information Center

JINTACCS Joint Interoperability of Tactical Command and Control Systems

JIT Just In Time (JAVA Compiler, proprietary to Sun)

JITC Joint Interoperability Test Command (US)

JIVE Jamming and Interception Vulnerability Estimator

JJ (1) Joprep Jiffy (obsolete SAC weather report form)

(2) Transmission is in Japanese

JJY Japanese standard frequency & time station [~]

JMA Japan Meteorological Agency

JMC (1) Joint movement center

(2) Jamaica (country code)

JML Journaline Markup Language (Fraunhofer)

JMPA Joint Military Postal Agency

JMRO Joint medical regulating office

JN Japanese Navy

JOC Joint Operations Center

JOPES Joint Operations Planning and Execution System

JOPREP Joint Operations Report

JORN (1) Jindalee Operational Radar Network (Australian OTH-B)

(2) Jindalee OTH Radar Network

JOSAC Joint Operational Support Airlift Center

JOTS Joint Interoperability Targeting System

JOVIAL Jules' Own Version of the International Algebraic Language, once used by USAF

JP (1) Joint publication

(2) Jumper (connection)

(3) Jet Propellant

JP-4 Jet Propellant #4 (military jet fuel, obsolete)

JP-7 Jet Propellant #7 (used in high-altitude recon a/c)

JP-8 Jet Propellant #8 (military jet fuel)

JPATS Joint Primary Aircraft Training System

JPEG Joint Photographic Experts Group (lossy compression for pictures)

JPL Jet Propulsion Laboratory, CA (NASA)

JPNIC Japanese Network Information Center

JRCC Joint Rescue Coordination Center

JREAP Joint Range Extension Applications Protocol

JRTC Joint Readiness Training Center (Ft. Polk, LA)

JSC Johnson Space Center, TX

JSC Joint Spectrum Center

JSF Joint Strike Fighter

JSMSw Joint Spectrum Management Spectrum for Windows (software)

JSORS Joint Advanced Special OPS Radio System

JSTARS Joint Surveillance Target Attack Radar System, aka "Joint STARS,"

E-8 surveillance aircraft

JSU All Japan Seamen's Union

JT4 Weak-signal MFSK mode designed for EME on microwave bands

JT65 Weak-signal MFSK mode designed for EME but now used also on HF

JT6M Weak-signal MFSK mode designed for 6-meter meteor scatter

JT9 Weak-signal MFSK mode optimized for LF/MF/HF, narrower than JT65

JTF Joint Task Force, usually US "War on Drugs"

JTF-4 Caribbean drug interdiction unit, out of Key West, part of JIATF-E

JTF-5 Pacific coast drug unit, part of JIATF-W

JTF-6 South & Central America drug unit, part of JIATF-South

JTFEX Joint Task Force Exercise

JTIDS Joint Tactical Information Distribution System

JTMS MSK mode designed for meteor scatter

JTRS Joint Tactical Radio System

JU JTIDS Unit (net member, like a voice "PU," only in Link-11)

JUH-MTF Joint user handbook for message text format

JUGFET Junction Gate Field-Effect Transistor

JWICS Joint Worldwide Intelligence Communications System

K (1) 1024 (decimal) of anything (loosely from hexadecimal)

(2) CW prosign: "Go Ahead," technically an "Invitation To Transmit"

k A thousand of anything, in decimal (short for kilo)

K Index Logarithmic, 3-hourly geomagnetic activity reading

k/c Kilocycles

K/cs Kilocycles per second = kiloHertz

KA9Q Packet radio protocol, from callsign of its inventor [~]

KAM Kantronics All-Mode (packet/digital controller)

KAWN Identifier attached to AWN weather products, as relayed by several

HF stations

KB (1) Keyboard

(2) Kilobyte

Kb Kilobit

kB Kilobit, kilobaud

kb/s kilobits per second

KBD Keyboard

kBd Kilobaud

Kbps Kilobits per second

KBS Korea Broadcasting System

kc Kilocycles per second, now kHertz

KCAS Knots Calibrated Air Speed

KCNA Korean Central News Agency

kcs Kilocycles per second, now kHertz

KDU Keypad-Display Unit

KFOR Kosovo Forces

KGB Komitet Gossudarstwennoy Besopasnostij (transliterated from Russian

by Klingenfuss), old USSR comint, replaced by FAPSI

KH Keyhole, optical recon satellite, KH-12 resembles Hubble

kHz Kilohertz

KIPM Illuminati Primum Materium (Pirate broadcaster)

KISS Keep it simple, stupid (packet radio mode/engineering golden rule)

km kilometer

kMc kilo-Megacycle, now Gigahertz

knot Nautical mile/hour [~]

KNRM Koninklijke Nederlandse Redding Maatschappij (Dutch SAR org.)

KOR (South) Korea (country code)

Kp Planetary K index

kph kilometer per hour

KRE (North) Korea (country code)

KSC Kennedy Space Center, Cape Canaveral, FL

KSCPAO Kennedy Space Center Public Affairs Office (NASA)

ksh Korn shell (Unix)

KSR Keyboard Send-Receive

kt knot (nautical mile per hour)

KT knots

KTAS Knots True AirSpeed

KTS knots

Ku-band 12-18 GHz microwave band

kV Kilovolt

KVA KiloVolt-Amp(s); can <> kW in highly reactive circuit

kW Kilowatt

L (1) Inductance (in Henrys)

(2) Left (with reference to runway designation)

L2TP Layer 2 Tunneling Protocol

LA Low altitude

Ladar Laser Radar

LAHSO Landing And Hold Short Operations

LAN Local Area Network

LANL Los Alamos (NM) National Laboratory

LANTAREA USCG Atlantic Area

LANTIRN Low Altitude Navigation and Targeting Infra Red for Night

LAO Laos (country code)

LAPD (1) Link Access Procedure D-Channel

(2) Los Angeles Police Department

LAPM Link access protocol for modems

LA-RICS Los Angeles Regional Interoperable Communications System

LASCO Large Angle and Spectrometric Coronagraph Experiment

LASER Light Amplification by Stimulated Emission of Radiation

LAST last observation before a break in coverage at a manual station

LAU Launcher Adapter Unit

LBA Logical Block Addressing (Disk access)

LBAR Limited area BARotropic (NCEP weather model)

LBN Lebanon (country code)

LBR Liberia (country code)

LBY Lybia (country code)

LC (1) Inductive/ Capacitive Network (circuit)

(2) Limited Coastal (service)

LCA St. Lucia (country code)

LCAC Landing Craft, Air-Cushioned (large hovercraft)

LCC Launch Control Center

LCD Liquid Crystal Display

LCMP Atlantic Composite Broadcast

LCP Link Control Protocol (PPP)

LCS Limited Coastal Station

LCU Landing Craft, Utility (US Army)

LD (1) Laser Diode

(2) Lethality Database (hazmat; often followed by percentage)

(3) Lunar Distance

LDAP Lightweight Directory Access Protocol

LDF Lightweight digital facsimile

LDOC Long Distance Operational Control (civil aviation)

LDP Landing Decision Point

LDR (1) Low Data Rate

(2) Loader

LDTWA Long Dual Trailing Wire Antenna (TACAMO)

LE Law Enforcement

LEARN Law Enforcement Amateur Radio Network

LEASAT Leased Satellite (US military comm)

LED Light Emitting Diode

LEDET Law Enforcement DETachment

LEO Low Earth Orbit ("Little LEO" = a type of mini-satellite)

LES Land Earth Station

LF (1) Low Frequency (30-300 kHz)

(2) Linefeed

LFMCW Linear Frequency-Modulated Continuous Wave

LFMICW Linear Frequency-Modulated Interrupted Continuous Wave

LFO Low frequency oscillator

LG Logistics Group

LGTR Laser Guided Training Round

LHCP Left-hand circular polarization

LIAR Liar Imitates Apply Recursively (recursive)

Lidar Light Detection & Ranging (light "radar")

LIE Liechtenstein (country code)

LIM (1) Lotus/Intel/Microsoft, original spec for PC extended memory

(2) Line interface module

LINCOMPREX Link Compression and Expansion, old ACSB system

Linux "Linus' Unix," open-source version of Unix

LIRL Low Intensity Runway Lights

LL Landline, "Lima Lima"

LLC (1) Logical Link Control

(2) Limited Liability Corporation (US)

LLCC Low Level Cloud Center (wx obs)

LLNL Lawrence Livermore National Laboratory

LLP Limited Liability Partnership (US)

LLTV Low Light Television

LLWAS Low Level Wind Shear Alert System

LMAO Laughing My A-- Off (Internet)

LMCC Land Mobile Communications Council

LMR Land Mobile Radio

LMS Location and Monitoring Services

ln Natural logarithm

LNA Low Noise Amplifier

LNB Low Noise amplifier/Block downconverter

LNBF Low Noise amplifier/Block downconverter Feedhorn

LMN Local Notice to Mariners (USCG)

LNP Local Number Portability (cell phones)

LO Local oscillator (of a receiver)

LOC (1) lines of communication

(2) location

log Common logarithm

LOGCAP Logistics Civil Augmentation Program

LOGPAC Logistics package

LOI Low Opportunity of Intercept

LOJACK Vehicle locator beacon activated & DF'd by police

LOL Laughing Out Loud (internet)

LORAC Long Range Accuracy (NASA booster recovery)

LORAN Long Range Navigation

LORAN-A Discontinued 160m Loran system

LORAN-C 100 kHz Loran system

LORAN-D Military Loran system

LOS (1) Loss Of Signal

(2) Line Of sight

LOTS logistics-over-the-shore

LOWFER Low-Frequency Experimental Radio (~164-190 kHz)

LP (1) Long Playing (old records)

(2) Low pass (filter circuit)

(3) Linking Protection (US mil ALE security)

(4) Log Periodic (antenna)

LPB Logistics preparation of the battlefield

LPD Line Printer Daemon

LPDA Log Periodic Dipole Array

LPDU HDFL: Link Protocol Data Unit

LPE Low-ass Equivalent

LPF Low-Pass Filter

LPFM Low-Power FM (broadcasting)

LPI Low Probability of Intercept

LPM Lines per minute

LPR Line Printer

LPRS Low-Power Radio Service (FCC)

LPT Logistics preparation of the theater

LPTV Low-Power TV (broadcasting)

LPVA Log Periodic V Array

LQA Link Quality Analysis (databursts heard from ALE radios)

LR Last Received (message)

LRA Landing Rights Airport

LRAD Long-Range Acoustic Device

LRC (1) Longitudinal Redundancy Check (computing)

(2) Logistics and Readiness Center

LRCOC Long Range Company Operational Control

LRIT Long Range Identification and Tracking (USCG)

LRRM Line Reflect-Reflect Match

LRS Long Range Surveillance (aircraft)

LS Last Sent (message)

LSASS Local Security Authority Subsystem Service (Windoze)

LSB (1) Lower Sideband

(2) Linux Standard Block

(3) Least Significant Bit/Byte

LSDIS Light and Special Division Interim Sensor (US Army)

LSE Logistics support element

LSG Large Signal Gain

LSI (1) Large scale integration (of chips)

(2) Locomotive System Integration

LST (1) Landing ship, tank

(2) Local Standard Time

LSV Logistic Support Vessel (US Army)

LTE Long Term Evolution

LTG lightning

LTP Long Term Predictor

LTR (1) Letter(s)

(2) LOgic Trunked Radio (Johnson)

LTRS Letters case (Baudot lower case)

LUF Lowest Usable Frequency (varies with path)

LUT Local User Terminal

LUU Parachute Flare

LWR lower

LZW Lempel-Ziv-Welch, lossless compression algorithm for data

M (1) Mega, meg, a million of anything, or 1,048,576 bytes (hex)

(2) minus, less than

(3) Below zero C

(4) Statute Mile

m Meter (39.37 inches)

M/S (1) Motor Ship (also MS, M.S.)

(2) Mile per second

m/s Meter per second

M/V Motor Vessel (also m/v)

M1FC Model 1 Full Capacity (Air traffic control)

mA milliamperes

MAC (1) Medium Access Control (computer networks)

(2) Military Airlift Command, now AMC

Mac Macintosh (computer)

MACOM Major command

MACS Military Aeronautical Communications System (Canada)

MacTCP TCP/IP package for Macintosh

MAFFS Modular Airborne Fire Fighting System (tank for C-130)

MAFOR Maritime weather forecast

MAGIS Marine Air-Ground Intelligence System

mAh miliamp-hour(s)

MAHRS Multiple Adaptive High frequency Radio System (German Mil)

MAIT Major Accident Investigation Team (CHP)

MAN Metropolitan Area Network, halfway between a LAN and a WAN

MANDRIL Message ANalysis and Data Reduction for the Integration of Links

MANPAD Man-Portable Air Defense

MAP Maghreb Arabe Presse

MAPI Mail/Messaging Applications Programming Interface

MAPS Mail Abuse Prevention System (Internet)

MARAD MARitime ADministration [~]

MARC MAchine Readable Catalog

MARCEMP Manual Relay Center Modernization Program (USN)

MARECS Maritime European Communications Satellite

MARLIN Mobile Ad-hoc Relay Line-of-sight IP Networking

MARO Maritime Air Radio Organization

MARS (1) Military Auxiliary Radio System (US)

(2) Maritime (mobile) Access & Retrieval System (ITU ship lookup)

MARSA Military Assumes Responsibility for Separation of Aircraft

MARSEC Marianas Sector (US Coast Guard) [~]

MASER Microwave Amplification by Stimulated Emission of Radiation

MASH Mobile Army Surgical Hospital, may be obsolete

MASM Macro-Assembler (computer code)

MATIC Mobility Assessment Test and Integration Center

MATS Military Air Transportation Service, became MAC, then AMC

MAU Media Attachment Unit, a network transceiver

MAVICA Magnetic Video Camera

MAYDAY Prosign: Distress traffic follows; repeated 3 times [~]

MB Megabyte

mb millibar

MBCS (1) Multi Byte Character Set (Unicode)

(2) Magnetic Bridge Current Sensor

MBDL Missile Battery Data Link

MBE Multi-Band Excitation (digital voice)

MBKS Multi-Button Key Set (telco)

MBO Mailbox

MBONE Multicast Backbone

Mbps Megabytes per second

MBA Multibeam Antenna

MBR Master Boot Record ("boot sector")

MCA Movement control agency

MCC (1) Master Control Center

(2) Movement control center

(3) Mobile Contingency Communications (USCG)

MCF Message Communication Function

MCFB Multi-Channel Fleet Broadcast

MCH Multi-mission Cutter Helicopter (USCG)

MCM (1) Multichip Module

(2) Mine Countermeasures

MCP (1) Mobile communications package

(2) Multimode Communications Processor (packet)

(3) Male chauvinist pig

MCPA Multi-Carrier Power Amplifier

MCPW Microstrip Co-Planar Waveguide

MCS Mission Communications System

MCS/P Maneuver Control System/Phoenix (US Army)

MCT Metal Oxide Semiconductor Controlled Thyristor

MCV Mobile Communications Vehicle

MCVFT Multichannel Voice Frequency Telegraph (multiplex RTTY)

MD5 Message-Digest, algorithm 5 (crypto, 128-bit)

MDR Medium Data Rate

MDS Multipoint Distribution Service

MDSU Mobile Diving and Salvage Unit (US Navy)

MDT (1) Mobile Data Terminal (usually police)

(2) Mountain Daylight Time, US zone includes Rockies

MEADS Medium Extended Air Defense System

MEBA Marine Engineers' Beneficial Association (Union)

MEC Medium Endurance Cutter (USCG)

med medical

MEDAFS Mine Warfare Environmental Data Analysis and Fusion System

MEDCOM Medical command

MEDEVAC Medical Evacuation [~]

MEDFER Medium-frequency Experimental Radio (low power ~510-1710 kHz)

MEDICAL Voice prosign attached to c/s of vessel with emergency medical