The non-wire cellular company, that operates in
radio frequencies from 824 to 849 MHz.
Amount of time required for a GPS unit to lock
onto 3 satellites to provide a "2D
View" of present position.
A waveguide or coaxial device used to mate two
dissimilar transmission lines or connectors.
Automatic Gain Control - A feedback control
circuit which maintains the gain or output power
level of an amplifier constant over a wide range
of input signal levels.
Time spent on a cellular or Digital PCS phone,
billed to the subscriber on a per second or per
Alumina (Aluminum Oxide, Al2O3)
Alumina-ceramic is used as the substrate material
on which is a deposited thin conductive and
resistive layer for thin film microwave
Amplitude modulation; a method of broadcasting in
which the desired audio or video signal modulates
the amplitude of a 'carrier' signal.
Information that is reproduced using a
continuously varying electronic signal.
A device that converts an analog input voltage to
a digital output word. These are also known as
ADCs, and have varying degrees of input range and
An array of metal rods or wires used to intercept
radio waves and convert them into electrical
currents. In microwave applications, often a
parabolic reflector with associated feed
The random and/or systematic variations in output
power amplitude. Usually expressed in terms of
dBc in a specified video bandwidth at a specified
frequency removed from the carrier.
AM-PM conversion represents a shift in the phase
delay of a signal when a transistor changes from
small-signal to large-signal operating
conditions. This parameter is specified for
communications amplifiers, since AM-PM conversion
results in distortion of a signal waveform.
Advanced Mobile Phone Service, the standard for
analog cellular telephones.
Automatic Network Analyzer - A
computer-controlled test system that measures
microwave devices in terms of their small signal
S-parameters. The use of this instrument by both
engineering and production permits quick and
accurate characterization of the input and output
impedance, gain, reverse isolation of individual
units and the degree of match between units.
The traditional method of transmitting voice
signals where the radio wave is based on
electrical impulses, which occur when speaking
into the phone.
An accessory circuit for an oscillator of filter
that permits its frequency to be changed by a
continuously varying signal.
The proportions of a TV or film picture,
generally given as the ratio of the width to
height. The standard TV picture has an aspect
ratio of 4x3, or 4:3. High-definition video
systems may have aspect ratios of 6x8 or greater.
Automatic (or Automated) Test Equipment
Acceptance Test Procedure
A device or network that absorbs part of a signal
and transmits the remainder with a minimum of
The wireline cellular carrier, usually the local
telephone company that operates on the
frequencies 869 to 894 MHz.
Metal applied to the side of the transistor wafer
opposite the active areas. Provides the collector
contact in bipolar transistors and permits the
transistor chips to be bonded to the package or
thin-film circuit substrate.
A transistor amplifier stage in which two
identical transistors are used and the input
signal and output power is equally divided
between them. This technique produces
approximately twice the output power of a single
transistor stage with generally improved dynamic
range and reduced VSWR.
A gain module of an amplifier that utilizes a 3
dB input splitter and a 3 dB output coupler to
combine the power of two or more paralleled FET’s.
Balanced modules have the characteristics of good
input and output VSWR, and the benefit of
indirect stability under adverse source and load
Ball Bond (MIC)
A bond formed when a ball-shaped end
interconnecting wire is deformed by
thermo-compression against a metallized pad. The
bond is also designated a nail head bond from the
appearance of the flattened ball.
The fixed transmitter/receiver with which a
mobile radio transceiver establishes a
communication link to gain access to the
public-switched telephone network.
The precise compass direction (in degrees) from
your present position to the next waypoint.
(Readings are selectable in either degrees
magnetic or true north).
Beryllium Oxide (BeO)
A ceramic material having very high heat
conductivity, good thermal shock resistance and
high strength. Used in metal/ceramic packages for
higher power microwave transistors and as
substrates in some MIC power amplifiers.
Built-in Test/Built-in Test Equipment - Some
products have provisions for connection to
customer-supplied test or test equipment that is
a part of the system in which the products are
used. Generally, a military/aerospace term for
equipment that contains an automatic self-testing
Bi Phase Shift Keying - A method of modulating a
microwave carrier so that data is translated into
90° phase shifts of the carrier.
Bonding Pad (MIC)
A metallized area at the end of a thin metallic
strip to which a connection is to be made.
Bonding Wire (MIC)
Fine gold or aluminum wire for making electrical
connections in hybrid circuits.
Computer Aided Design/ Computer Aided
A device is cascadable if the output port of one
such device can be connected to the input port of
another such device without additional impedance
matching being required.
A series of microwave amplifier stages connected
in sequence (sometimes including limiters,
attenuators or other elements) to produce the
desired gain, power output and other performance
A metallic enclosure which can be made to
resonate at a desired frequency. Primarily used
to describe a cavity filter, which is a
highly-selective tuning element at microwave
frequencies that may be used as the
frequency-determining element of an oscillator,
or as a lowpass, bandpass or highpass filter.
Generally of fixed frequency or mechanically
tunable over a very limited frequency range.
The portion of the microwave spectrum
(4,000-8,000 MHz) used most widely for
distribution of video programs by satellite to
Common Channel Interoffice Signaling System #7, a
Consultative Committee for International
Telephony and Telegraphy
Cellular Digital Packet Data
The geographic area served by a single low-power
transmitter/receiver. A cellular system's service
area is divided into multiple "cells".
See: Beryllium Oxide, Alumina
Certificate of Compliance
A document shipped with a customer-ordered
product when required by contract that indicates
that the product meets or exceeds all
customer-specified performance characteristics.
The width of the spectrum band taken up by a
radio signal, usually measured in kilohertz
(kHz). Most analog cellular phones use 30-kHz
The uncased and normally leadless form of an
electronic component part, either passive or
active, discrete or integrated.
The interconnection of the number of electrical
elements and/or devices, performing desired
A passive microwave device consisting of 3-ports
that allows the signal entering each port to pass
to the port adjacent to it (either clockwise or
counter-clockwise) but not to the port in the
A cable consisting of one center conductor to
carry a signal, surrounded concentrically
(coaxial) by an insulating dielectric and a
separate outer conductor (braid or metal jacket)
which acts as a shield.
Code-Division Multiple-Access (CDMA)
A digital technology that uses a low-power signal
"spread" across a wide band-width. A
call is assigned a code instead of a certain
frequency. Using the identifying code and a low
power signal, a large number of callers can use
the same group of channels.
The process of powering up a new GPS receiver for
the first time and having it search out and lock
onto the satellites by itself, without the
benefit of initialization data. This procedure is
slower and may require up to 15 minutes for
initial satellite acquisition only.
Combined Ripple and Spurious
The worst case transmission loss (in dB) within
the YIG filter 3 dB passband due to the presence
of passband spurious and or passband ripple
Communication Satellite Corporation, providing
satellite communication services and chartered by
the federal government.
A component used to switch, limit, modulate or
attenuate microwave signals.
Conversion Compression Point (1 dB)
The specification which states the RF input power
(in dBm) at which the IF output power will
increase only 9 dB for a 10 dB increase in RF
input power at stated LO power level. This
specification provides an indication of the mixer
two-tone intermodulation performance and usually
is of most concern in high level mixing
The ratio (in dB) of the IF output power of a
mixer to the RF input power. All conversion loss
measurements and specifications are normally
based on the mixer being installed in a system
with wideband 50 ohm resistive terminations on
all ports and a stated LO signal power level
A Waveguide device used to sample the microwave
transmissions by means of coupling (combining)
signals asymmetrically. May be of the crossguide
or directional variety. Available at various
coupling levels (typically 10 to 50 dB below the
signal of interest).
Course Over Ground (COG)
The current direction (in degrees) that a GPS
user is actually traveling, selectable in degrees
magnetic or true north.
Or Cross Guide Coupler. See "Coupler"
Cross Modulation Distortion
The amount of modulation impressed on an
unmodulated carrier when a signal is
simultaneously applied to the RF port of a mixer
under specified operating conditions. The
tendency of a mixer to produce cross modulation
is decreased with an increase in conversion
compression point and intercept point.
Cross Track Error (XTE)
Digital reading on GPS steering screens that
indicates precisely how far off the user is, to
the right or left of the center of the course.
Cordless telephone-first generation; any variety
of North American, European, and Japanese analog
Cordless telephone-second generation; a digital
cordless telephone standard generally used in
residential cordless phone, a telepoint
application, or a small-office WPBX system.
Cordless Telephone 3rd Generation (standards
Cellular Telecommunications Industry Association
Continuous Wave - Signal of constant amplitude.
Used to differentiate between the performance of
a microwave component for continuous power levels
vs. pulsed signals. For example, "This
amplifier will accept up to +30 dBm CW (or
continuous) or up to +50 dBm peak (up to 5
microsecond duration with low duty cycle) input
power without performance degradation." Also
used to describe an unmodulated carrier.
Decibel - A logarithmic expression of ratios. Can
be found by taking ten times the common logarithm
of the ratio of two power levels, or 20 times the
common logarithm of the ratio of two voltage
Decibel related to the signal carrier level
Decibels related to 1mW - the standard unit of
power level used in microwave work. For example,
0dBm= 1mW, +10 dBm = 10mW, +20dBm=100 mW, etc.
Decibels related to isotropic. Relates the gain
of an antenna relative to an isotropic (perfectly
spherical pattern) antenna.
Direct Broadcast Satellite; a system that sends
TV broadcasts directly from a communications
satellite to home antennas, or dishes.
Digital Cross Connect.
Digital Cross Connect
This is basically a passive box containing a
bunch of chokes that provides patching and
recabling capability. Its primary reason for
existence is that it keeps radio frequency
signals from feeding into digital circuitry.
A device that converts a digital input word to an
analog voltage output. These are also known as
DACs, and have varying degrees of input
resolution and range.
Digital communication service at 1800 MHz. An
extension of the Global System for Mobile
Dynamic Digital Cordless Telephone
Digital Data System
Digital European Cordless Telephony (standard)
The compression in the IF output power from a
desired RF input signal caused by a second high
level signal being simultaneously applied to the
RF port of a mixer. As a rule of thumb, in low
level mixers, a desired RF input 3 dB below the
mixer conversion compression point will begin to
An uncased discrete or integrated device obtained
from a semiconductor wafer.
Attachment of a die or chip to the hybrid
A high Q, temperature stable ceramic microwave
resonator that is used in microwave oscillator
circuits. It can exist in any regular geometrical
form of resonates in various modes at frequencies
determined by its dimensions and shielding
Dielectric Resonator Material
Low loss, high permittivity (Er = 30 to 40)
temperature stable ceramic material. Some of the
commonly used materials are barium titanate,
titanium niobiate, etc. The composition of these
materials can be controlled to achieve any
frequency variation with temperature between +10
Differential GPS (DGPS)
A system devised initially by the U.S. Coast
Guard to improve GPS accuracy levels to within 5
meters. It employs a land-based, fixed position,
DGPS reference receiver to first calculate the
Selective Availability errors, and then transmit
the necessary correction factors to mobile GPS
receivers in the area. DGPS systems require an
added beacon receiver to communicate with the
standard GPS unit.
The phenomenon of movement of matter at the
atomic level from regions of high concentration
to regions of low concentration.
An accessory circuit for an oscillator or filter
which permits its frequency to be varied by
varying a digital "word." A digital
driver is also an accessory circuit interfacing a
switch or attenuator to a digital command
Digital European Cordless Telecommunications
A digital cordless telecommunications system
intended initially for WPBX applications, later
to be used in the home market. DECT supports both
voice and data communications.
A method of transmitting an analog (continuously
variable) signal using the computer's binary
code, 0s and 1s. Digital transmission offers a
cleaner signal than analog technology. Cellular
systems providing digital transmission are
currently in operation in several locations.
The parabolic antenna used for transmitting and
receiving signals from communication satellites.
Changes in a signal that involve the addition of
spurious tones at frequencies not present in the
original signal. In harmonic 'distortion' the
spurious tones are at integral multiples of the
original frequency. In 'intermodulation'
distortion, discordant tones appear at the sums
and differences of two original frequencies.
Distance To Go (DTG)
Digital readout (selectable in miles, nautical
miles or kilometers) displayed only when
navigating to a waypoint. It simply indicates the
remaining distance from present position to the
Domestic communication satellite (as opposed to
one confined to military uses).
Integrated assembly of components required to
convert microwave signals to an intermediate
frequency range for further processing. Generally
consists of an input filter, local oscillator
filter, IF filter, mixer and frequently an LO
frequency multiplier, plus one or more stages of
IF amplification. May also incorporate the local
oscillator, AGC/gain compensation components and
The satellite-to-earth microwave channel and
related components such as the earth station
receiving equipment. The satellite contains a
downlink transmitter. Downlink components in the
earth station are involved with the reception and
processing of satellite-transmitted signals.
The power level of the local oscillator signal
applied to the LO port of a mixer. Operating a
mixer with the maximum recommended LO drive level
will result in the best two tone performance,
lowest conversion loss and flattest conversion
loss vs. frequency characteristics, reduced
mixer-generated intermodulation products and will
minimize 1/f noise in the output signal. A
higher-than recommended LO power level will
result in an increased noise figure and higher LO
feed-through at both the RF and IF ports of the
Dry Nitrogen Filled
A special process in which a unit is sealed and
filled with dry nitrogen to help prevent fogging
and internal corrosion.
Digital Signal Processing (or Processors)
Digital Sequence Spread Spectrum
A phone that operates on both analog and digital
Device voltage temperature coefficient.
The range from the minimum, which is at a level
at or below the amplifiers' internally-generated
noise, to a maximum input signal level that a
component can accept and amplify without
distortion. In regard to mixers, the range of RF
input power levels over which a mixer can operate
within a specified range of performance. The
upper limit of the mixer dynamic range is
controlled by the conversion compression point
(also a function of LO drive), and the lower
limit is set by the mixer noise figure.
Expanded Advanced Mobile Phone Service
The ground station that receives (downlink) and
sends (uplink) signals to and from communication
Electronic Counter-Countermeasures - Equipment
and techniques to allow electronic systems such
as radar and communications to operate
effectively while attempts are being made to
disrupt or jam their operation.
Electronic Countermeasures - Equipment and
techniques to reduce the effectiveness of
opposing electronic systems such as radar and
communications. Includes techniques such as chaff
and barrage jamming as well as sophisticated
methods to deceive the systems without indication
to the opposing operators that their systems are
Electronic Data Interchange
The maximum output frequency deviation that can
be achieved without significantly affecting
oscillator performance characteristics. This is
achieved by adjusting the varactor diode coupled
to the dielectric resonator. Typical DSO
electronic tuning ranges are +0.1 of the center
Electronic Intelligence - The intelligence
information product of activities engaged in the
collection and processing, for subsequent
intelligence purposes of foreign,
non-communications (radar, for example)
electromagnetic radiation. Does not include
communications intelligence (COMINT) or radiation
from radioactive sources such as nuclear
Electronic Support Measures - Electronic warfare
activities involving the search for, and
interception, location, recording and analysis
of, radiated electromagnetic energy for the
purposes of exploitation in the support of
military operations (includes ELINT, SIGINT).
Electromagnetic Interference - Unintentional
interfering signals generated within or external
to electronic equipment. Typical sources could be
power-line transients, noise from switching-type
power supplies and/or spurious radiation from
oscillators. EMI is suppressed with power-line
filtering, shielding, etc.
Electronic news gathering; the use of video
cameras and tape recorders in place of film
systems for news coverage by TV stations.
Enhanced TDMA Access
European Telecommunications Standards Institute.
One of the European organizations responsible for
establishing common industry wide standards for
The specific proportions of the constituents of
an alloy having the lowest melting point. The
system goes from totally molten to totally solid
without going through a slushy range at the
Electronic Warfare - Electronic warfare is
military action involving the use of
electromagnetic spectrum and actions to retain
friendly use of the electromagnetic spectrum.
Federal Communications Commission. The U.S.
government agency responsible for allocation of
radio spectrum for communication services.
Frequency Division Multiple Access
The term "ferrite" refers to various
iron-containing compounds. Most commonly, in the
field of electronics, the term refers to cores of
various shapes, which are made of these
materials. One of the properties of inductors
that have ferrite cores is that their inductance
varies with the current through them.
A ferrite tuner is a ferrite core inductor that
can be used to tune a resonant circuit.
Field Effect Transistor - See GaAs FET.
Microwave amplifiers (GaAs FET or bipolar
transistor) using negative feedback in the
amplification stages. Used to control input and
output impedance, increase operating bandwidth
and help minimize performance variations caused
by inherent variations in transistor parameters.
Frequency Hopping Spread Spectrum
A set of scanning lines that, when interlaced
with another set, makes up the 'frame,' or
complete TV picture.
A concave junction formed where two surfaces
In general microwave usage, a miniature hermetic
package for MIC components, designed for a
minimum height, with pins for RF and DC
connections existing through the sides (narrowest
dimensions), and designed to be surface mounted
or "dropped in" to a cutout in a
micro-strip printed circuit board. The leads and
the largest surface of the package are in
Floating-Point Operations Per Second
Maximum Frequency of Oscillation - The frequency
at which unilateral gain equals unity.
FM Noise/Phase Noise
The short term frequency variations in the output
frequency that appear as energy at frequencies
other than the carrier. It is usually expressed
in terms of dBc or as an RMS frequency deviation
in a specified frequency removed from the
Future Public Land Mobile Telecommunications
The particular patch of the Earth's surface
reached by the signal from a communications
A complete TV picture, comprising two fields. The
North American transmission standard calls for 30
frames transmitted per second.
The number of cycles per second of an
electromagnetic transmission. 1 hertz (Hz) = 1
cycle per second; 1 kilohertz (kHz) = 1,000; 1
megahertz (MHz) = 1,000,000; 1 Gigahertz (GHz) 1
A method of transmission in which the desired
signal modulates (varies) the frequency of a
The maximum output frequency deviation from a
specified tuning function under specified
conditions. May be expressed in MHz, PPM, or
Frequency Drift Over Operating Temperature, Max.
The maximum change in output frequency as a
result of a specified change in operating
temperature. In regard to the oscillators, a
measure of the change in frequency over the
specified operating temperature range. It is
commonly expressed as parts-per-million per
degree Celsius (PPM/°C) or as a percentage
figure. From a system applications view, the
frequency set at room temperature in +/- total
parts per million.
The difference between the maximum values of the
oscillator frequency when the phase angle of the
load impedance reflection coefficient varies
through 360 degrees. Typically, this load
impedance has a VSWR of 1.67:1.
The incremental output frequency change produced
by an incremental change in supply voltage
(MHz/V). If supply voltage ripple, frequency
range and amplitude are not specified,
measurements will be conducted at a DC rate.
Usually presented as the minimum and maximum
frequencies between which a particular component
will meet all guaranteed specifications.
The principal measures of the fidelity of any
sound reproducing device.
The use of the same frequency in different
geographic areas by managing the propagation of
the frequency. In cellular systems, their low
power allows frequencies assigned to one channel
to be limited to the boundaries of a signal cell.
Therefore, the carrier is free to reuse the
frequencies again in other cells in the system
without causing interference. In satellite
systems, the use of directional spot beams
similarly allows non-overlapping geographic areas
to reuse the same frequency, and the use of
linear polarized signals allows the use of the
same frequency within the same geographic area.
A form of artificial intelligence, stored on a
computer chip, that enables a camcorder or
television to make complex adjustments in focus
or picture quality based on ideal models.
Gain-Bandwidth Product - (also called transition
frequency). It is the frequency at which the
magnitude of the small-signal common-emitter
current gain equals unity.
Frequency at 3 dB Gain Point - The frequency at
which gain has reduced 3 dB from the gain at a
specified reference frequency.
The variation of gain over a specified frequency
Associated Gain - The tuned gain of a device when
it is biased for optimum noise figure.
Gallium Arsenide Field Effect Transistor - (also
called GaAs MESFET for metal Epitaxial
Semiconductor Field Effect Transistor). A field
effect transistor with a reverse-biased
Schottky-barrier gate fabricated on a gallium
arsenide substrate. Roughly equivalent to a
silicon MOSFET, GaAs FETs are depletion mode
devices. Because charge carriers reach
approximately twice the velocity as in silicon,
for a given geometry a given gain can be reached
at about twice the frequency.
A single stage of gain or a cascaded series of
RF gap in RF cavities.
The orbit of a communications satellite that
allows it to move at the precise speed at which
the Earth is rotating, thus remaining at the same
spot in the sky relative to the Earth. The orbit
is 35,900 km (22,300 mi.) above the Earth and
directly over the equator.
Gigahertz (billions of hertz).
Maximum Available Gain - The gain achieved when a
transistor is unconditionally stable and the
input and output ports are simultaneously
conjugately matched. Also designated MAG.
Global Positioning Satellite
Global System for Mobile Communications, or Group
Special Mobile - the Pan-European digital
1 dB Gain Compression Point - The level of gain
from a device which is 1 dB less than the gain
measured under small-signal conditions for a
given input level. See also P1dB.
Cellular systems are designed so that a phone
call can be initiated while driving in one cell
and continued no matter how many cells are driven
through. The transfer to a new cell, known as a
handoff, is designed to be transparent to the
cellular phone user. During a cellular
conversation, when the user reaches the edge of
the service area of a cell, computers in the
network assign another tower in the next cell to
provide the phone with continuing service.
Harmonic Intermodulation Distortion
The ratio (in dB) of distortion to the IF output
waveform caused by mixer-generated harmonics of
the RF and LO input signals. This characteristic
is extremely dependent on input frequency, RF and
LO signal levels, and the precise impedance
characteristics of all terminations at the
Signals which are coherently related to the
output frequency. In general, these signals are
integer multiples of the output frequency.
Haterojunction Bipolar Transistor Technology
High-definition TV, a technology aimed at
producing a video picture containing as much
detail as a 35-mm motion picture, with a
wide-screen aspect ratio and stereophonic sound.
The unit of measuring frequency signals (one
cycle per second).
A transformer or waveguide circuit having four
terminals (or four ports) so arranged that a
signal entering at one terminal will divide and
emerge from the two adjacent terminals but will
be unable to reach the opposite terminal. Hybrid
Junctions (quadrature hybrids) are widely used in
microwave circuits as power dividers and
combiners (e.g., in balanced amplifiers,
Hybrid Integrated Circuits
The combination of thin-film or thick-film
circuitry deposited on substrates with chip
transistors, capacitors and other components.
Thin-film construction is used for microwave
integrated circuits (MICs).
In regard to threshold detectors, an upward
change in the threshold voltage to ensure
positive switching activity.
The phenomenon causing the values of the magnetic
flux density to lag behind the values of the
magnetizing force so that the increasing and
decreasing fields differ in magnitude. In regard
to YIG-Tuned oscillators, a magnetic lag effect
of the magnetic components of a YIG device that
occurs when the tuning coil current is changed.
Hysteresis is measured in terms of the maximum
resulting frequency difference at a particular
magnet current when the device is turned from
high to low frequency range.
I dB Gain Compression
(1 dB GCP, Gain Compression Point, P1dB) - The
maximum output power of an amplifier at which
amplification is nearly linear (high power levels
result in compression). As input power applied to
an amplifier is increased, some point will be
reached where a 10 dB increase in input signal
results in only 9 dB of output signal increase -
this is the 1 dB gain compression point. Other
compression points such as 0.1 dB or 2 dB are
Integrated Digital Loop Carrier
IF (Intermediate Frequency)
In superheterodyne receiving systems, the
frequency to which all selected signals are
converted for additional amplification, filtering
and eventual direction.
(or Image-Rejection Mixer) - A form of branched
mixer in which the two output frequencies (LO +
Fin LO - Fin) are separated, isolated and brought
out to separate ports. Thus, as its name implies,
this mixer configuration rejects the undesired
Opposition or resistance to the flow of
electrical current. Impedance is the term used in
non-direct current (DC) applications, while
resistance is used for DC.
The peak-to-peak variations of the carrier
frequency due to external variations with the
unit operating at a fixed frequency at any point
in the tunable frequency range.
Refers to the simple procedure of telling a new
GPS receiver "where it is", when it is
turned on for the first time. Information
required includes: approximate present position
in latitude/longitude coordinates; and the
current local time and date.
The transmission loss measured in dB at that
point in the passband that exhibits the minimum
Integrated Spurious Output Power
The total power of all spurious outputs in and
out of the specified frequency range.
International Telecommunications Satellite
Organization; 112-member consortium of countries
formed (1964) to launch and operate
A figure (expressed in dBm) that indicates the
linearity and distortion characteristics of a
microwave component. It represents the point
where the fundamental output and spurious
responses (usually third-order) intersect, when
plotted on a log-log scale with output power
ordinate and input power as abscissa.
Intercept Point 3rd Order
Third Order Intercept Point (IP3) - The
intersection point of the fundamental Pout vs.
Pin extrapolated line and the third-order
intermodulation products extrapolated line. IP3
is highly dependent on the LO and RF frequency,
the LO drive level, and the impedance
characteristics of all terminations at the
The conductive path required to achieve
connection from a circuit element to the rest of
Those connections of conductors made within a
circuit on the same substrate.
A method of semiconductor doping in which
selected dopants are ionized and accelerated at
high velocity to penetrate the semiconductor
substrate and become deposited below the surface.
Third Order Intercept Point or Intercept Point
Interim Standard 41 - the cellular inter-system
handoff and cell delivery
Interim Standard Number 54, the dual-mode (analog
and digital) cellular standard in North America.
In the analog mode, IS-54 conforms to the AMPS
Integrated Services Digital Network. A switched
network providing end-to-end digital connectivity
for simultaneous transmission of voice and data
over multiplexed communications channels.
Industrial, Scientific, and Medical. It is the
unlicensed radio band in North America and some
European countries. It is also refereed to as
part 15.247, the FCC regulation that defines the
parameters for use of the ISM bands in the United
States, including power output, spread-spectrum,
International Standards Organization
The ratio (in dB) of the power level applied at
one port of a mixer to the resulting power level
at the same frequency appearing at another port.
Commonly specified isolation parameters of mixers
1. LO to RF port: The degree of attenuation of
the LO signal measured at the RF port with the IF
port properly terminated.
2. LO to IF port: The degree of attenuation of
the LO signal measured at the IF port with the RF
port properly terminated.
3. RF to IF port: The degree of attenuation of
the RF signal measured at the IF port with the LO
port properly terminated.
Normally the inverse isolation characteristics
(such as RF to LO, IF to LO, and IF to RF) are
essentially equivalent in a double-balanced
A device that permits microwave energy to pass in
one direction while providing high isolation to
reflected energy in the reverse direction. Used
primarily at the input of communications-band
microwave amplifiers to provide good reverse
isolation and minimize VSWR. Consists of
microwave circulator with one port (port 3)
terminated in the characteristic impedance.
The deliberate radiation, re-radiation or
reflection of electromagnetic energy with the
object of impairing the use of electronic
devices, equipment or systems by the enemy.
Equipment may consist of rudimentary CW or noise
transmitters, broadband transmitters or complex
systems that generate deceptive signals.
Kilohertz (thousands of hertz).
The portion of the microwave spectrum
(12,000-18,000 MHz) used in many newer video
satellite transmissions, particularly in Direct
Broadcast Satellite (DBS) systems designed for
Light-emitting Diode: Solid-state devices that
glow when electric current is applied.
Relating to analog signals and their processing.
Also refers to the operating range of an
amplifier where little or no distortion occurs.
The input power level at which the input/output
characteristics exhibit compression (i.e., the
transfer function becomes nonlinear in that the
output increases less than 1 dB for a 1 dB
increase in input).
Any deviation from a best fit straight line
approximation under specified conditions. In
regard to YIG-tuned and voltage-controlled
oscillators, the maximum output frequency
deviation from a best fit straight line
approximation of the tuning curve under specified
load and constant temperature conditions. In
regard to YIG-tuned filters, the maximum
deviation (in MHz) of the measured resonant
frequency vs. coil current curve from the ideal
linear tuning line over the YIG filter's
operating frequency range.
Local Oscillator - An oscillator used in
superheterodyne receiver which when mixed with an
incoming signal results in a sum or difference
frequency equal to the intermediate frequency of
Low-power TV; TV station with limited
broadcasting range, often built in rural areas in
order to pick up and amplify distant signals.
Also used for broadcast programming to specific
Maximum Available Gain - Gain at a frequency
where the transistor is unconditionally stable
(k>1) and the input and output ports are
simultaneously, conjugately matched. Also
designated: GZ(max), G(max).
The output frequency deviation due to magnetic
field measured in kHz/Gauss.
Master antenna television; a distribution system
in which a single antenna is used to feed
broadcast TV signals to the occupants of a
building or development. SMATV provides the same
service but uses a dish antenna to pick up
Multipoint distribution service; a method of
distributing video programs from a central high
point (usually a tall building) by microwave to
subscribers equipped with special antennas.
Sometimes called 'wireless cable.'
Maximum output frequency deviation that can be
achieved without significantly affecting
dielectrically stabilized oscillator
characteristics. This is achieved by adjusting
the air gap spacing between the dielectric
resonator and tuning screw located directly above
the resonator. Typically, mechanical tuning range
is +/-1% of the center frequency.
Metropolitan Statistical Area
An MSA denotes one of the 306 largest urban
population markets as designated by the U.S.
government. Cellular operators are licensed in
Megahertz (millions of hertz).
Microwave Integrated Circuit - In the microwave
industry, a hybrid using thin- or thick-film
conductors and passive components on a ceramic
substrate combined with chip-form active and
Microwave Integrated Circuit Amplifier
(Microstripline) A transmission line consisting
of a metallized strip and a solid ground plane
metallization separated by a thin, solid
dielectric. This transmission line configuration
is used since it permits accurate fabrication of
50 transmission line elements on a ceramic or PC
High frequency radio waves lying roughly between
infrared waves and radio waves (above 1 GHz = 1
billion cycles per second). Microwaves are
generated by electron tubes, such as the klystron
and the magnetron, or solid state devices with
built-in resonators to control the frequency or
by oscillators. Microwaves have many applications
for radio, television, radar, test and
measurement communications, distance and location
measuring, and more.
Million Instructions Per Second
The input/output terminals of a mixer, are
identified as RF, LO and IF. In most double
balanced mixers, the LO and RF are either
transformer or transmission line-coupled to the
mixer diodes, and therefore have a limited
low-frequency response; while the IF port is
usually direct-coupled with an essentially
unlimited low frequency response. In upconverting
applications, the low frequency input signal is
often applied to IF port with the
higher-frequency output signal being taken from
the RF port.
The generation of sum and difference frequencies
which result from applying two AC wave forms to a
non-linear circuit element. In mixer
applications, with a signal of frequency Frf
applied to the RF port and a signal fLO applied
to the LO port, the resulting signal at the IF
port will consist of two carriers (or sidebands)
of frequencies Frf + fLO and Frf - fLO with
internally-generated LO and RF harmonics.
Monolithic Microwave Integrated Circuit designed
using either silicon or GaAs devices.
Mobile Telephone Switching Office (MTSO)
The MTSO is the central computer that connects a
cellular phone call to the public telephone
network. The MTSO controls the entire system's
operations, including monitoring calls, billing,
Modulator/Demodulator; a device that incorporates
both in a single package.
Modulation or Tuning Sensitivity
The slope or the first derivative of the tuning
curve in MHz/V. Where necessary, the fine gain or
incremental slopes and the ratio of the slope
should be specified over the frequency range.
Modulation or Tuning Sensitivity Variation
The charge in the first derivative as a function
of tuning voltage and/or frequency. Usually
specified as percentage change of the first
derivation over an incremental frequency range.
Direction of tuning for measurement should be
specified. Also may be specified as the ratio of
the maximum to minimum value of the first
Modulation Response Bandwidth
The modulation frequency range where, for a
reference deviation bandwidth, all included
modulation frequencies of equal amplitude will
result in no less than a ratio of 1.414 (3 dB) of
minimum to maximum deviation. The types of
modulation should be specified as well as the
internal impedance of the modulation source.
Mean Time Between Failure - A calculated figure
representing the estimated average lifetime of a
device before it fails.
Reception of one or more reflected signals along
with a direct broadcast signal, producing
distortion in stereo FM and ghost images in
A method of accommodating two channels of
information on one carrier.
GPS receiver that rotates a small number of
channels to multiple satellites in order to
provide current positioning data. Typically,
multiplexing receivers require more time for
satellite acquisition and lock on, and are not as
accurate as parallel channel receivers.
Multiplexing receivers are also more prone to
lose satellite fix in dense woods compared to
parallel channel GPS receivers.
Narrowband Advanced Mobile Phone Services
Transmission to a specific, small audience (such
as Japanese speaking people for example), often
via low-power, UHF stations.
A microwave test system that characterizes
devices in terms of their complex small-signal
scattering parameters (S-parameters).
Measurements involve determining the ratio of
magnitude and phase of input and output signals
at the various ports of a network with the other
ports terminated in the specified characteristic
impedance (generally 50 ohms) - See ANA
Noise Figure (NF)
The ratio (in dB) between the signal-to-noise
ratio applied to the input of the microwave
component and the signal-to-noise ratio measured
at its output. It is an indication of the amount
of noise added to a signal by the component
during normal operation. Lower noise figures mean
less degradation and better performance.
The lowest input signal power level that will
produce a detectable output signal from a
microwave component, determined by the thermal
noise generated within the microwave component
itself. The noise floor limits the ultimate
sensitivity to the weak signals of the microwave
system, since any signal below the noise floor
will result in an output signal with a
signal-to-noise ratio of less than one and will
be more difficult to recover.
The amount of thermal noise present in a system.
Used in microwave communications and sometimes
radar, it is the equivalent of noise figure
expressed in Kelvins (e.g., an amplifier with 1.5
dB noise figure has an effective noise
temperature of 120 K).
Signals which are not coherently related to the
Non-Operating Signal Rejection
The amount of signal rejection (in dB) referenced
to the insertion loss, measured at any point
across the frequency range with zero current
through the tuning coil.
Non-Recurring Engineering - Charges made to a
customer to pay for the engineering costs
required to develop a custom part or to modify a
standard part to meet special customer-specified
characteristics. May be charged in a lump sum or
spread over the production run.
Off Resonance Isolation
The amount of signal rejection (in dB) referenced
to the passband minimum insertion loss measure
data point outside the YIG filter passband
Off Resonance Spurious
The amount of suppression (in dB), referenced to
the passband minimum insertion loss, of spurious
responses outside the YIG filter passband skirts.
The maximum VSWR seen by the oscillator at the
output port, referenced to 50°.
The frequency of the desired output of the
component. The undesired frequency components may
include harmonics, subharmonics, 3/2 harmonics or
nonharmonic spurious signals.
The minimum and/or maximum output power at the
output frequency under all specified conditions.
Usually the specified conditions are temperature,
load, VSWR and supply voltage variations. It is
typically expressed in dBm or milliwatts (mW).
Output Power at 1 dB Gain Compression -
Essentially the maximum output power available
from the transistor while providing linear
amplifications. Also designated: PO-1 dB, and in
numerous other ways. See also G1dB.
The container for a circuit and/or component(s)
with terminals to provide electric access to the
inside of the container. In addition, the
container could provide hermetic and
environmental protection for, and a particular
form factor to, the assembly of electronic
A metallized area on the surface of an active
substrate as an integral portion of the
conductive interconnection pattern to which bonds
or test probes may be applied.
Phase Alternation Line color system, the color TV
broadcast standard used in most of Western Europe
and. in modified form, in China and Brazil.
Parallel Channel Receiver
GPS receiver that simultaneously tracks multiple
satellites to provide the fastest, most reliable
and accurate navigational data, under the most
The peak to peak value (in dB) of ripple
occurring within the 3 dB passband referenced to
the minimum insertion loss.
The additional transmission loss (in dB) within
the 3 dB passband attributable to the presence of
spurious resonance (absorption) modes. Skirt
spurious modes are referenced to a line tangent
to the YIG filter passband skirt. Spurious modes
within the minimum loss (ripple) region are
referenced to the normalized filter response
Passband Temperature Drift
The change in resonant frequency (at a fixed coil
current) associated with the change in operating
The best VSRW as measured at any point within the
3 dB passband.
The formation of an insulated layer directly over
a circuit or circuit element to protect the
surface from contaminants, moisture or particles.
Personal Memory Card International Association
Personal Communications Network
Printed Circuit Board
Personal Communications System
Personal Digital Assistant
(2[f2-f1]/[f2+f1]) x 100 where f1 and f2 are the
lower and upper endpoints, respectively, of the
An approach to digital coding that records only
the portions of sound or picture: that we
believed to be audible or visible.
Personal Communications System
Used in Canada to describe next-generation
digital cellular service. Also used to describe a
loosely defined future ubiquitous
telecommunications service that will allow
"anytime, anywhere" voice and data
communication with personal communications
Personal Handy Phone. It is Japan's standard for
digital cordless telephones.
The process of forming a circuit pattern in metal
film by light hardening a photo sensitive plastic
material through a photo negative of the circuit
and etching away the unprotected metal.
A diode made by diffusing the semiconductor so
that a thin intrinsic layer exists between the P
and N-doped regions
(positive-intrinsic-negative). Such diodes do not
rectify at microwave frequencies but behave as
variable resistors controlled by the applied DC
Small holes occurring as imperfections which
penetrate entirely through the film elements,
such as metallization films or dielectric films.
A picture element; the "building
blocks" of a liquid crystal display (LCD).
The greater the number of vertical and horizontal
pixels, the better the screen resolution and
Provides an overhead "bird's eye" view
of current position relative to the waypoints and
event marker/icons previously saved. A dotted
line marks the shortest route to the chosen
waypoint, and a recorded plot trail displays the
path taken so far.
Short for "population". If the covered
area of a cellular carrier includes a population
base of 1 million people, it is said to have 1
million POPS. The financial community uses the
number of potential users as a measuring stick to
value cellular carriers.
One of the primary navigational data screens that
emphasize the present position latitude/longitude
coordinates, as well as other helpful
Post Tuning Drift
The maximum change in frequency ( fPTD) from the
frequency measured at the beginning of the time
interval (t1). The time interval (t1-t2) shall be
referenced to the application of a tuning command
(t0). The period of measurement ends at time
The final stage of amplification in a radio, the
purpose of which is to raise the signal to the
level required by the antenna system.
A passive resistive network that equally divides
power applied to the input port between any
particular number of output ports without
substantially affecting the phase relationship or
Power Output @ 1 dB Gain Compression
See 1 dB Gain Compression.
Power Output Variation or Flatness
The maximum peak to peak power variation at all
output frequencies in the tunable frequency range
under all specified conditions.
To aid in soldering or adhesion, small circles or
spares of the solder or epoxy are punched out of
thin sheets. These preforms are placed on the
spot to be soldered or bonded, prior to the
placing of the object to be attached.
Current location on the face of the Earth, in
terms of the specific latitude/longitude
coordinates, displayed in degrees/minutes/and
thousandths of a minute.
A pointed conductor used in making electrical
contact to circuit pad for testing.
The ability to customize existing split panel
window groupings with specific combinations of
Total power dissipated in a transistor.
Post, Telephone, and Telecommunications.
Administrative European government organizations
responsible for mail and telecommunications
services within their respective countries.
Amplifiers specifically optimized and
characterized for fast pulse droop and minimum
overshoot - to handle complex input waveforms and
pulse-modulating RF signals.
Generally a measure of the sharpness of the
resonance or frequency selectivity of a tuned
circuit or filter.
Quadrature Partial Response - A method of
modulating a microwave carrier with two parallel
streams of filtered digital bit streams carried
in phase quadrature relationship. QPR normally
uses 3-level partial response and occupies
one-half the bandwidth of QPSK. QPR-7 uses
7-level partial response and occupies one-fourth
the bandwidth of QPSK.
Quadrature Phase Shift Keying (quadriphase) - A
method of modulating a microwave carrier with two
parallel streams of NRZ digital bit streams so
that data is translated into 90° phase shifts of
Having a characteristic 90° phase shift. Used to
describe a coupler in which the two output
signals are 90° out of phase, and in
telecommunications for modulation techniques such
as QPR and QPSK.
The representation of a continuous quantity, such
as a sound wave, by a series of numeric values.
System of communication employing electromagnetic
waves propagated through space. Because of their
varying characteristics, radio waves of different
lengths are employed for different purposes and
are usually identified by their frequency. The
shortest waves are the highest frequency, or
numbers of cycles per second; while the longest
waves have the lowest frequency, or fewest cycles
per second. In honor of the German radio pioneer
Heinrich Hertz, his name has been given to the
cycle per second: (hertz, Hz); 1 kilohertz (kHz)
is 1000 cycles per second, 1 megahertz (MHz) is 1
million cycles per second, and 1 Gigahertz (GHz)
is 1 billion cycles per second. Radio waves range
from a few kilohertz to several Gigahertz. Waves
of visible light are much shorter. In vacuum, all
electromagnetic waves travel at a uniform speed
of about 300,000 km (about 186,000 mi.) per
Radio waves are used not only in radio
broadcasting but also in wireless devices,
telephone transmission, television, radar,
navigational systems, and communication. In the
atmosphere the physical characteristics of the
air cause slight variations in velocity, which
are sources of error in such radio-communications
systems as radar. Also, storms or electrical
disturbances produce anomalous phenomena in the
propagation of radio waves.
Because electromagnetic waves in a uniform
atmosphere travel in straight lines and because
the earth's surface is spherical, long distance
radio communication is made possible by the
reflection of radio waves from the ionosphere.
Radio waves shorter than about 10 m (about 33
ft.) in wavelength - designated as very high,
ultrahigh, and super high frequencies (VHF, UHF,
and SHF) - are usually not reflected by the
ionosphere; thus, in normal practice, such very
short waves are received only within
line-of-sight distances. Wavelengths shorter than
a few centimeters are absorbed by water droplets
or clouds; those shorter than 1.5 cm (0.6 in) may
be absorbed selectively by the water vapor
present in a clear atmosphere.
A typical radio-communication system has two main
components, a transmitter and a receiver. The
transmitter generates electrical oscillations at
a radio frequency called the carrier frequency.
Either the amplitude or the frequency itself may
be modulated to vary the carrier wave. An
amplitude - modulated signal consists of the
carrier frequency plus two sidebands resulting
from modulation. Frequency modulation produces
more than one pair of sidebands for each
modulation frequency. These produce the complex
variations that emerge as speech or other sound
in radio broadcasting, and in the alterations of
light and darkness in television broadcasting.
A middleman who buys at discounted wholesale
rates or large volume and then resells them at
Resonant Frequency or Passband Frequency
The arithmetic mean of the low and high
normalized 3 dB frequencies.
When expressed in dB is the ratio of reflected
power to incident power. It is a measure of the
amount of reflected power on a transmission line
when it is terminated or connected to any passive
or active device. Once measured, it can be
converted by equation to reflection coefficient
that can be converted to VSWR.
Radio Frequency - Generally referring to any
frequencies at which the radiation of
electromagnetic energy is possible. Also used as
designation for frequencies at which the
radiation of electromagnetic energy is possible.
Also used as designation for frequencies below
approximately 50 to 100 MHz (100 - 300 MHz is
very high frequency, 300 MHz - 1000 MHz is
ultra-high frequency, 1000 MHz and up is
Devices that operate at radio frequency, which
are used to accelerate the beam. They operate by
alternating an electric field across a gap (of
which there are two in each RF cavity).
RF Leakage is defined as the amount of energy
which "leaks" from the connector and/or
component. Although RF Leakage will vary with
frequency, it is typically tested at only one
frequency. Leakage, like Insertion Loss, is
expressed in dB. Very large negative dB values
indicate that the device does not radiate much
Using a cellular phone in a city other than the
one in which you live.
Consists of two or more waypoints combined in a
course of travel. It provides the automatic
capability to navigate through several waypoints,
without having to reprogram the unit after
arriving at each one. Once programmed into the
GPS unit, the route provides the option of
navigating forward through the waypoints or in
Rural Service Area
The FCC divided the less populated areas of the
country into 428 RSAs and licensed two service
providers per RSA.
Satellite Status Display
An information screen that shows technical data
about each satellite in view. Information
includes receiver channel numbers; actual
satellite ID numbers; status of satellite
tracking (T) or searching (S); satellite
elevations and azimuths; signal to noise ratios
(SNR) (the higher the number, the better); and
dilution of precision ratings (GDOP is most
important; the smaller the number, the better
With respect to microwave components, indicates
the maximum output power available when the
component is driven beyond its linear region.
Saturated Output Power
The maximum output power of a component. As input
power is increased, some point will be reached at
which the output power will maximize. This is
known as the saturated output power (PSAT) and
typically occurs at approximately 5 dB gain
Savable Plot Trails
The capability to save your actual plot trail
crated on the plotter screen, thereby enabling
the GPS user to either backtrack the course
immediately, or save and retrace the trip at a
A method of altering a cable or satellite
transmission signal so that it can be seen only
by those who own special decoders.
Sequentiel Couleur avec Memoire (sequential color
with memory); the color TV broadcast standard
used in France and its former possessions and, in
modified form, in the USSR and some Eastern
Selective Availability (S/A)
The system used by the U.S. Department of Defense
to intentionally degrade the accuracy of
satellite GPS signals being transmitted to
civilian GPS receivers. All brands of civilian
GPS receivers are equally affected by S/A. With
random S/A on, the government has guaranteed that
civilian GPS accuracy levels will consistently be
100 meters or less, 95% of the time. If S/A is
turned off, those accuracy levels will improve to
10 to 15 meters consistently.
A measure of a tuner's ability to receive
stations at closely spaced frequencies without
The normalized change in YIG component's center
frequency resulting from a change in tuning coil
current, specified in MHz/mA.
The time (tst) required for the output frequency
to enter and stay within a specified error band
(fst) centered around a reference frequency (fr)
after application of a step input voltage (VCO)
or current (YTO). The time (tr) shall be
specified for determining the reference frequency
(fr). The period of measurement ends at the
reference time (tr)
The portions of the passband curve above the
upper and below the lower frequency points at
which full off-resonance isolation is achieved.
The amount of additional transmission loss,
referenced to the normalized filter skirt curve,
outside the 3 dB passband, caused by the spurious
resonance (absorption) modes.
The rate that the oscillator frequency can change
in response to a step input waveform should be
Small Signal Gain
The gain characteristics of an amplifier
operating in the linear amplification region.
Small signal gain is typically measured at least
10 dB below the input power level that creates 1
dB gain compression.
Small Signal Gain Flatness
Small signal gain deviation (stated as + and -
and not p-p) from a flat reference line measured
over the operating frequency of the amplifier at
a fixed temperature.
Specialized Mobile Radio. A private business
service using mobile radiotelephones and base
stations communicating via the public phone
S/N or SNR
Signal-to-Noise Ratio - The ratio of signal power
to noise power in a specified bandwidth,
expressed in dB.
Speed Over Ground (SOG)
Digital reading that indicates current ground
speed. (Selectable in miles per hour, knots or
kilometers per hour).
Scattering Parameter - Scattering parameters are
a group of measurements taken at different
frequencies which represent the forward and
reverse gain, and the input and output reflection
coefficients of a microwave component when the
input and output ports of the component are
terminated in a specified impedance - usually 50
Magnitude - The length of the vector in the polar
Angle - The direction of the vector in the polar
dB - 10 log 10 (Power)
S11 - S-parameter input reflection coefficient -
Expresses the magnitude and phase of the input
reflection coefficient, measured with the input
and output ports terminated in a pure resistance
of 50 ohms.
S21 - S-Parameter forward transfer coefficient -
Expresses the forward voltage gain magnitude and
phase, measured with the input and output ports
terminated in pure resistance of 50 ohms.
S12 - S-parameter reverse transfer coefficient -
Expresses the reverse voltage gain (sometimes
called isolation) magnitude and phase, measured
with the input and output ports terminated in a
pure resistance of 50 ohms.
S22 - S- parameter output reflection coefficient
- Expresses the magnitude and phase of the output
reflection coefficient, measured with the input
and output ports terminated in a pure resistance
of 50 ohms.
Specification Temperature Range
The range of temperatures as measured near the
component or device must meet all guaranteed
specifications unless otherwise noted.
The complete range of electromagnetic waves that
can be transmitted by natural sources such as the
sun, and man-made radio devices. Electromagnetic
waves vary in length and therefore have different
characteristics. Longer waves in the
low-frequency range can be used for
communications, while shorter waves of high
frequency show up as light. Spectrum with even
shorter wavelengths and higher frequencies are
used in X rays.
Originally developed by the military, spread
spectrum radio transmission essentially
"spreads" a radio signal over a very
wide frequency band to make it difficult to
intercept and difficult to jam.
Spurious-Free Dynamic Range
The range of input signals lying between the
tangential sensitivity level and an upper signal
level at which generated in-band spurious outputs
exceed the tangential level.
Spurious Signal and Outputs
Undesired signals produced by an active microwave
component, usually at a frequency unrelated to
the desired signal or its harmonics. Spurious
outputs are both harmonically and
non-harmonically related signals. Their tolerable
amplitude should be specified within and out of
the frequency range of the oscillator. Typical
values range from -60 dBc to -80 dBc.
Signaling System 7 Protocol
SSB Conversion Loss
In most applications, only one of the signals
(fRF+fLO) or (fRF-fLO) appearing at the IF port
of a mixer is of interest; therefore, only one of
these signals (or sidebands) is considered when
determining conversion loss in 3 dB higher than
the conversion loss when both sidebands are
considered (double sideband conversion loss).
Shows a graphic "highway view" of the
GPS user's course over ground. Provides helpful
instructions as to how far off course, which
direction to steer, right or left, to make
corrections, and displays related navigational
data pertaining to the waypoint.
Straight Line Navigation
The standard method of navigation used by
recreational GPS products. When commanded to
"navigate to a waypoint", the unit
draws a straight, dotted line from the present
position to the selected waypoint. It's the
shortest, most direct route to the destination.
Caution: Straight line navigation does not take
into account any obstacles in the path; interim
waypoints may be required to navigate safely
A transmission line consisting of a conductor
above or between extended conducting surfaces.
The wafer of ceramic on which the thin-film
circuit is deposited in hybrid microwave
integrated circuit construction.
The minimization of undesired side effects in
circuit operations (e.g., two tone
intermodulation suppression, usually through a
design compromise or the addition of specialized
Ambient Temperature - TA is usually room
temperature and is normally assumed to be 25°C
if not otherwise specified.
Case Temperature - The external temperature of
the component package. This temperature is higher
than the ambient temperature due to the power
dissipation of the device.
Group Delay - The time required for a signal to
pass from input to output.
Time Division Multiple Access
A circuit element or device such as an amplifier,
divider, resistor, antenna, etc., placed at the
end of a transmission line.
Total Harmonic Distortion; A measure of all of
the spurious signals added by a sound-reproducing
See: Wedge Bond
A thin-film (usually less than 10,000 Angstroms
thickness) deposited onto substrate by an
accretion process such as vacuum evaporation,
sputtering or pyrolytic decomposition.
Telecommunications Industry Association. The
North American organization established to
provide industry wide standards for
Time Division Multiple Access
The cellular industry established a TDMA digital
standard in 1989. TDMA increases the channel
capacity by chopping the signal into pieces and
assigning each one to a different time slot.
Current technology divides the channel into three
time slots, each lasting a fraction of a second,
so a single channel can be used to handle three
Time To Go (TTG)
Digital reading showing the time remaining from
current position to the next waypoint. This
function takes into account Distance To Go (DTG),
and Velocity Made Good (VMG) to give as closely
as possible the amount of time left to reach the
waypoint. Displayed in hours, minutes and
seconds, it will continue counting down until the
waypoint is reached.
Junction Temperature - The temperature of the
emitter-base junction of a transistor.
Maximum Junction Temperature - Maximum allowable
transistor junction temperature. It is normally
200°C for silicon for high reliability.
One of several metal hermetic "cans"
originally developed as transistor packages.
Cellular Digital Standard Committee under TIA
A waveguide device used to convert from waveguide
to coaxial transmission lines.
The conductive connections between circuit
elements that carry signal power. Wire, coaxial
cable and waveguide are common examples.
One communications satellite "channel"
consisting of an uplink receiver, intermediate
signal processing components and downlink
transmitter. One transponder may be configured to
carry many different signals.
True and Magnetic North
True north is the top of the world, where all
lines of longitude converge. Magnetic north is
the location our compasses point to; it lies
several hundred miles to the south of true north,
in Arctic Canada.
Storage Temperature - The maximum ambient
temperature at which a non-operating transistor
may be stored without damage.
Television Receive Only- Small satellite earth
stations designed to receive satellite relayed
television programming having no provision for
transmitting to the satellite.
Tuning Input Impedance
The small-signal impedance seen at the tuning
input port at a specified modulation frequency or
Continuously increasing or decreasing output
frequency for a continuously increasing tuning
voltage f(V1)(fV2) for V1V2.
The ability of the oscillator to repeat a
frequency within specified limits, f, when the
original command voltage is reapplied after
having been commanded through an arbitrary tuning
history. The repeatability window f equals
ft1-ft2 with constant tuning voltage over the
time interval t1 to t2. Temperature stability and
dwell time are to be specified.
Tuning Response Time
The time required for the filter response to come
within a specified value of the desired frequency
for a specified frequency sweep.
The slope of the tuning curve in MHz/mA.
Two-Tone, Third-Order Intermodulation Distortion
The total amount of distortion (dB relative to
desired waveform) to the output signal waveform
that exists when two simultaneous input
frequencies are applied to the RF port of a
mixer. Two-tone, third-order intermodulation
distortion products are described by 2fR2-Fr1+/-
fLO and by 2fR1-Fr2+/- fLO. The higher the
third-order intercept point and conversion
compression of a mixer, the lower the
intermodulation for given input signals will be.
A process involving the use of ultrasonic energy
and pressure to join two materials.
The earth-to-satellite microwave link and related
components such as earth station transmitting
equipment. The satellite contains an uplink
receiver; uplink components in the earth station
are involved with the processing and transmission
of signal to satellite.
A diode which, when operated in a reversed-biased
condition, provides a junction capacitance that
varies with applied voltage. Used as an
"electrically variable" capacitor in
tuned circuits (such as those in varactor-tuned
oscillators) or as frequency multiplier.
Velocity Made Good (VMG)
Digital speed reading (similar to SOG) that
compensates for progress being made toward a
waypoint. For example, when traveling directly on
course toward a waypoint, the SOG and VMG
readings may match. However, when traveling off
course, the VMG reading will typically be slower
than the SOG. VMG is a true indication of the
speed being made to selected waypoint.
Vertical Blanking Interval
VBI - The 21 lines between TV frames,
transmitted, like the frames, at a rate of 30
times per second. These lines are used for
auxiliary information, including teletext, closed
captions, and test signals.
Any region in the metallization exposing oxide,
that was not caused by a scratch.
Vapor Phase Epitaxy (epitaxial) - An epitaxial
layer on a transmitter wafer or chip formed by
condensing a single-crystal layer of
semiconductor material on the surface of the
When impedance mismatches exist, some of the
energy transmitted through will be reflected back
to the source. Different amounts of energy will
be reflected back depending on the frequency of
the energy. VSWR (Voltage Standing Wave Ratio) is
a unitless ratio ranging from 1 to infinity,
expressing the amount of reflected energy. A
value of one indicates that all of the energy
will pass through, while any higher value
indicates that a portion of the energy will be
A single slice of substrate material (silicon or
gallium arsenide) upon which many transistors are
fabricated. The wafer is then tested, scribed and
broken apart to produce transistor chips.
A unit of electrical or acoustical power.
Electrical power is the product of voltage and
current. Acoustical power is proportional to
A transmission line specific to microwave
communications consisting of a conducting metal
outer shell, and filled with air or a vacuum.
Waveguide is also used as the basis for numerous
components such as crossguide couplers, filters,
hybrid combiners and circulators/isolators.
Location, spot or destination
(latitude/longitude) that can be stored in memory
to be recalled and used at a later time for
navigation purposes. Simply think of it as an
A bond between a gold wire and a gold metallized
substrate using a wedge-shaped tool.
Thermocompression boning combines temperature and
pressure to make a wedge bond. Ultrasonic bonding
combines ultrasonic energy with the pressure of
Wide Area Network
(Wilkenson splitter) - An equal-phase power
splitting/combining circuit used as an
alternative to quadrature hybrid couplers in some
balanced amplifier designs. Tends to have
narrower operating bandwidth than quadrature
Includes all the constituent components of wire
electrical connection such as between the
terminal and the semiconductor die. These
components are the wire, metal bonding surfaces,
the adjacent underlying insulating layer (if
present) and substrate.
Wireless local area network. A computer network
that allows the transfer of data and the ability
to share resources, such as printers, without the
need to physically connect each node with wires.
WLANs may also offer mobility within an office or
Wireless private branch exchange. The WPBX offers
business users the ability to make and receive
calls using cordless telephones anywhere on a
CCITT Specification & Protocol for Public
Packet-Switching Networks - Layer 3
Yttrium-Iron Garnet is a synthetic crystalline
ferrite containing yttrium and iron (Y3Fe6O16).
If a single crystal sphere of YIG is immersed in
a magnetic field, and RF energy is coupled into
it via a magnetic loop, the crystal will resonate
at a frequency linearly proportional to the
magnetic field strength. In practical YIG-tuned
oscillators and filters, the magnetic field is
derived from an electromagnet and the resonant
frequency of the YIG sphere is proportional to
the current flowing through the magnetic coil.
A microwave filter using YIG sphere as the
A microwave tunable oscillator using the YIG
sphere as the frequency determining element.
YIG-tuned oscillators can be made with Gunn-diode
technology or, add an internal buffer amplifier
to minimize frequency pulling, and produce
additional output power capability. YIG-tuned
oscillators are fundamental oscillators; they do
not contain frequency multiplication circuitry.
3 dB Bandwidth
The frequency span (in Mhz) between the points on
the selectivity curve at which the insertion loss
is 3 dB greater than the minimum insertion loss.
Also called 3 dB passband