Appendix A. Acronyms

This appendix includes the most commonly used acronyms in the RF and wireless industry. Some of the more arcane acronyms have been omitted because they do not experience widespread use. Because of the nature of the wireless industry, this list will almost certainly be incomplete. (The darn engineers can abbreviate things faster than publishers can publish.)

AC Alternating current,

power from a wall outlet.

AGC

Automatic gain control, control of a variable gain amplifier.

AM Amplitude modulation,

a type of modulation.

AMPS Advanced mobile phone service,

first generation cellular in the United States.

ASIC Application-specific integrated circuit,

a custom integrated circuit.

BASK Binary amplitude shift keying,

digital amplitude modulation.

BER Bit error rate,

the number of errors per second in a transmitted signal.

BPF Bandpass filter,

a type of filter.

BPSK Bi-phase shift keying,

a type of phase modulation.

BTA Basic trading area,

a small geographical area allocated for PCS.

CDMA Code division multiple access,

spread spectrum for mobile phones.

CDPD Cellular digital packet data,

wireless data communication using cellular phones.

CL Conversion loss,

the insertion loss of a mixer.

CW Continuous wave,

an RF system in which the transmitter is always on.

D-AMPS Digital AMPS,

a digital version of AMPS.

dB Decibels,

a relative measure of signal strength.

DBS Direct broadcast satellite,

TV signals from satellites direct to the home.

DC Direct current,

power from a battery.

DCS Digital communication services,

second generation cellular in Europe.

DGPS Differential GPS,

more accurate GPS.

DPDT Double-pole double-throw,

a type of RF switch.

DQPSK Differential quadrature phase shift keying,

a type of phase modulation.

DRO Dielectric resonator oscillator,

a type of oscillator.

DSP Digital signal processing (or processor),

a type of electrical signal processing.

DSSS Direct sequence spread spectrum,

a type of spread spectrum.

DTO Dielectrically tuned oscillator,

a variable DRO.

EIRP Effective isotropic radiated power,

the power radiated from a satellite's antenna.

EMC Electromagnetic compatibility,

acceptable levels of EMI.

EMI Electromagnetic interference,

a type of RF noise.

FCC Federal Communications Commission,

U.S government airwaves regulators.

FDMA Frequency division multiple access,

breaks up conversations by frequency.

FHSS Frequency hopping spread spectrum,

a type of spread spectrum.

FM Frequency modulation,

a type of modulation.

GaAs Gallium arsenide,

a type of semiconductor material.

GEO Geosynchronous orbit,

22,000 miles above Earth.

GMSK Gaussian minimum shift keying,

a type of phase modulation.

GPS Global positioning system,

a satellite constellation used to determine location.

GSM Group special mobile,

a popular cellular standard in Europe.

HBT Heterojunction bipolar transistor,

a new type of fast transistor.

HDTV High definition television,

next generation digital TV.

HEMT High electron mobility transistor,

a very high frequency transistor.

HF High frequency,

frequency between 3 and 30 MHz.

HPA High power amplifier,

a type of amplifier used at the output of a transmitter.

HPF High pass filter,

a type of filter.

Hz Hertz,

the measure of a signal's frequency in cycles per second.

IC Integrated circuit,

multiple electrical components on a single semiconductor.

IF Intermediate frequency,

one of the signals used by a mixer.

IL Insertion loss,

the loss a signal experiences in a passive component.

IMD Intermodulation distortion,

a type of RF signal noise.

IMT International mobile telephone,

third generation cellular.

ISM Industrial, Scientific, Medical,

a family of frequency allocations for such use.

ITU International Telecommunications Union,

the FCC for the world.

JTACS Japan TACS,

Japanese version of TACS.

LAN Local area network,

computers hooked together.

LCC Leadless chip carrier,

a type of RF component package.

LDMOS Laterally diffused metal oxide semiconductor,

a type of transistor.

LEO Low Earth orbit,

a few hundred miles above Earth.

LHC Left hand circular,

a type of polarization.

LMDS Local multipoint distribution service,

a high frequency fixed wireless service.

LMR Land mobile radio,

a wireless application.

LNA Low noise amplifier,

a type of amplifier used at the input of a receiver.

LNB Low noise block converter,

an LNA and a mixer in the same package.

LO Local oscillator,

one of the inputs to a mixer.

LPF Low pass filter,

a type of filter.

LTCC Low temperature cofired ceramic,

a multilayer MIC circuit.

MCM Multichip module,

an RF subsystem hybrid.

MCPA Multicarrier power amplifier,

a type of very linear power amplifier.

MESFET Metal semiconductor field effect transistor,

a high frequency transistor.

MIC Microwave integrated circuit,

a particular circuit technology.

MMIC Monolithic microwave integrated circuit,

an RF integrated circuit.

MOSFET Metal oxide semiconductor field effect transistor,

a low frequency transistor.

MSA Metropolitan statistical area,

an urban geographical area allocated to cellular.

MSC Mobile switching center,

the brains of the cellular system.

MSK Minimum shift keying,

a type of phase modulation.

MTA Metropolitan trading area,

a large geographical area allocated for PCS.

MTSO Mobile telephone switching office,

the brains of the cellular system.

NADC North American digital cellular,

a digital cellular standard.

NF Noise figure,

the measure of quietness of an LNA.

NMT Nordic mobile telephone,

a cellular standard used in Scandinavian countries.

NODS Near object detection system,

a radar system for the rear bumper of a car.

OCXO Oven-controlled crystal oscillator,

a type of oscillator.

OEM Original equipment manufacturer,

a manufacturer.

PA Power amplifier,

same as HPA.

PAE Power added efficiency,

a measure of a power amplifier's efficiency.

PCB Printed circuit board,

a particular circuit technology.

PCN Personal communications network,

a new wireless application.

PCS Personal communication services,

second generation cellular in the United States.

PDC Personal digital cellular,

a Japanese cellular standard.

PHEMT Pseudomorphic high electron mobility transistor,

a very high frequency transistor.

PLL Phase locked loop,

a feedback technique used in an oscillator.

PLO Phase locked oscillator,

an oscillator which utilizes a PLL.

PM Phase modulation,

a type of modulation.

PSTN Public switched telephone network,

the local phone company.

QAM Quadrature amplitude modulation,

a type of complex modulation.

QPSK Quadrature phase shift keying,

a type of phase modulation.

RBOC Regional Bell operating company,

the baby Bells.

RF Radio frequency,

shame on you.

RFI Radio frequency interference,

unwanted RF signals.

RFIC Radio frequency integrated circuit,

self explanatory.

RHC Right hand circular,

a type of polarization.

RSA Rural statistical area,

a rural geographical area allocated for cellular.

SAW Surface acoustic wave,

an electrical signal as a sound wave.

Si Silicon,

a type of semiconductor material.

SMR Specialized mobile radio,

a cellularlike mobile phone service.

SMT Surface mount technology,

a method of mounting components on a PCB.

SPDT Single-pole double-throw,

a type of switch.

SPST Single-pole single-throw,

a type of switch.

SSPA Solid state power amplifier,

a power amplifier made from transistors.

TACS Total access communications systems,

similar to AMPS.

TCXO Temperature controlled crystal oscillator,

a type of oscillator.

TDMA Time division multiple access,

breaking up signals into multiple time slots.

TWT Traveling wave tube,

a type of RF amplifier.

TWTA Traveling wave tube amplifier,

same as a TWT.

UHF Ultra high frequency,

frequency between 300 MHz and 3 GHz.

VCO Voltage-controlled oscillator,

a type of oscillator.

VCXO Voltage-controlled crystal oscillator,

a type of oscillator.

VGA Variable gain amplifier,

a type of amplifier.

VHF Very high frequency,

frequency between 30 and 300 MHz.

VSAT Very small aperture terminal,

a multipoint-to-point satellite system.

VSWR Voltage standing wave ratio,

the measure of a component's match.

VTO Voltage tuned oscillator,

same as VCO.

VVA Voltage variable attenuator,

an attenuator whose attenuation can vary.

WCDMA Wideband CDMA,

CDMA used for PCS telephony.

WLAN Wireless local area network,

computers connected without wires.

WLL Wireless local loop,

wireless local telephone service.

YIG Yttrium-Iron-Garnet,

an alloy used in oscillators.