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Index Of Abbreviations Used In This Web Site

Abbreviation Expanded Words Comments
AC Alternating Current
ADC Analog to Digital Converter
AF Audio Frequency Low frequency signals usually below 100 kHz. 
AGC Automatic Gain Control
ALC Automatic Level Control
AM Amplitude Modulation
Amp Amplifier
ASK Amplitude Shift Keying
BJT Bipolar Junction Transistor
BPF Band Pass Filter
CMOS Complimentary Metal Oxide Silicon (IC)
DAC Digital to Analog Converter
DBM Double Balanced Mixer
DC Direct Current
Direct Conversion Refers to a receiver or transmitter topology with I and Q base-band processing 
DFM Design For Manufacture A collection of philosophies intended to streamline the manufacture of products and reduce overall cost
DFT Discrete Fourier Transform Fourier Transform applied to a time sampled system
DRFSA Direct RF Signal Acquisition Receiver topology based on the use of a high speed ADC used to digitize RF signals
DRFSS Direct RF Signal Synthesis Transmitter topology based on the use of a high speed DAC used to generate RF signals
DSP Digital Signal Processing
FET Field Effect Transistor Three terminal voltage operated amplifying device
FFT Fast Fourier Transform Computationally efficient physical implementation of a DFT
FIR Finite Impulse Response (filter)
FPGA Field Programmable Gate Array Integrated Circuit "sea of gates" - configurable by software to form  arbitrary digital functions
FSK Frequency Shift Keying
FT Fourier Transform Converts time domain representation to a frequency domain representation
GASFET Gallium Arsenide FET Microwave version of a FET using Gallium Arsenide (not silicon)
HPF High Pass Filter
IC Integrated Circuit Semiconductor "Chip" containing active and passive devices to form a circuit
IDFT Inverse DFT Inverse Fourier Transform applied to a frequency sampled system
I/F Interface
IFFT Inverse FFT Computationally efficient physical implementation of an IDFT
IF Intermediate Frequency Output signal following frequency conversion (usually below RF or LO frequencies)
IFT Inverse Fourier Transform Converts time domain representation to a frequency domain representation
IGBT Insulated Gate Bipolar Transistor Composite high power device based on a MOSFET + JFET + Bipolar structure
IIR Infinite Impulse Response (filter)
IQ In Phase & Quadrature Phase Complex signal representation Viq { t } = Vi{ t } + j Vq{ t }
JFET Junction FET Depletion mode P-gate, N-drain-source or N-gate, P-drain-source
LASER Light Amplification by Stimulated Emission of Radiation Used to create a "coherent" light source (i.e. narrow spectral bandwidth) based on multiple internal reflections through an externally powered  medium that increases optical energy energy
LC Inductor-Capacitor Series or Parallel tuned circuit reference
LCR Inductor-Capacitor-Resistor Series or Parallel tuned circuit reference with resistive loss
LDO Low Drop Out (regulator) Linear regulator with low differential input-output voltage (ΔV) requirement (good ones have ΔV < 0.2 Volts)
LDR Light Dependent Resistor Cadmium Sulphide or Cadmium Selenium based optical device with light dependent resistance. Has a similar optical response to the human eye
LED Light Emitting Diode Diode that produces moderate bandwidth light output from a DC power input. Used as a low cost indicator or torch bulb substitute. Versions are available from infrared to ultra violet
LPF Low Pass Filter
MOSFET Metal Oxide Silicon FET FET using an insulating oxide layer under a metal date
MUSCAF Multiple User Software Configurable Arbitrary Format Receiver or Transmitter architecture using DSP technology with flexible functionality
NN Neural Network
OCXO Oven Controlled XTAL (Crystal) Oscillator Medium cost versions offer 0.01 to 0.1 ppm stability, expensive versions ca achieve 0.001 ppm
OFDM Orthogonal Frequency Division Multiplex/Modulation
OpAmp Operational Amplifier
PC Personal Computer
PCB Printed Circuit Board
PIN P-Intrinsic-N Type P-N junction with intermediate non doped semiconductor
PN P-N Type
PNP P-N-P Type P-Type semiconductor has excess of +holes, N-Type has excess -electrons
PSK Phase Shift Keying
PUT Programmable Unijunction Transistor
QAM Quadrature Amplitude Modulation
RC Resistor-Capacitor Simple series, parallel or 2-port filter combination
RF Radio Frequency Generic term for systems with frequency dependant parasitic contributions
SCR Silicon Controlled Rectifier
SiC Silicon Carbide
SiGe Silicon Germanium
SETI Search For Extra Terrestrial Intelligence
TCXO Temperature Compensated XTAL (Crystal) Oscillator Temperature stability of 2 ppm over a wide temperature range is typical
TL Transmission Line
TRF Tuned Radio Frequency Early receiver approach based on cascaded RF amplification prior to signal detection
TTL Transistor-Transistor Logic
UFO Unidentified Flying Object Any object regardless of origin
UJT Unijunction Transistor
USB Universal Serial Bus Trendy interface from a device to a PC
Varicap Variable Capacitance (diode)
VCO Voltage Controlled Oscillator Variable frequency oscillator controlled with a Varicap diode
XTAL Crystal





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Ian R Scott 2007 - 2008