Electrical Engineering Dictionary - part 114

MISO

See

miss

the event when a reference is made

to an address in a level of the memory hierar-
chy that is not mapped in that level, and the
address must be accessed from a lower level
of the memory hierarchy.

miss probability

the probability of falsely

announcing the absence of a signal.

miss rate

the percentage of references to a

cache that do not find the data word requested
in the cache, given by 1

− h where h is the

hit rate. Also miss ratio.

miss ratio

See

miss rate

missile terminal guidance seeker

lo-

cated in the nose of a missile, a small radar
with short-range capability that scans the area
ahead of the missile and guides it during the
terminal phase toward a target such as a tank.

mix-and-match lithography

a lithogra-

phic strategy whereby different types of litho-
graphic imaging tools are used to print differ-
ent layers of a given device.

mixed A/D simulator

a simulator that is

capable of simulating combined analog and
digital circuitry.

mixed method coordination

in case of

any mixed method both direct coordination
instruments — as in the direct method — and
the dual coordination instruments — as in the
price method — are used by the coordinator
to modify local decisions until the coordina-
tion objectives are met; different combina-
tions of direct and dual coordination instru-
ments may be used, and so a variety of mixed
methods can be conceived.

mixed mounting technology

a compo-

nent mounting technology that uses both
through-hole and surface-mounting tech-

nologies on the same packaging and inter-
connecting structure.

mixer

a nonlinear device containing either

diodes or transistors, the function of which is
to combine signals of two different frequen-
cies in such a way as to produce energy at
other frequencies. In a typical down con-
verter application, a mixer has two inputs and
one output. One of the inputs is the mod-
ulated carrier RF or microwave signal at a
frequency

, the other is a well controlled

signal from a local oscillator or VCO at a fre-
quency

. The result of down conversion is

a signal at the difference frequency

−f

which is also called the intermediate fre-
quency

. A filter is usually connected to

the output of the mixer to allow only the de-
sired IF frequency signal to be passed on for
further processing. For example, for an RF
frequency of 10.95 GHz (=10,950 MHz) and
an LO frequency of 10 GHz (=10,000 MHz),
the IF frequency would be 950 MHz.

mixing amplifier

See

harmonic amplifier

See

maximum likelihood estimation

MLR

See

multilayer resist

MMF

See

magnetomotive force

MMIC

See

monolithic

microwave

integrated circuit

MMSE

See

minimum mean square

estimator

minimum mean square error

MMU

See

memory management unit

MMX register

a register designed to hold

as many as eight separate pieces of integer
data for parallel processing by a special set
of MMX instructions. An MMX register can
hold a single 64-bit value, two 32-bit val-
ues, four 16-bit values, or eight-byte integer
values, either signed or unsigned. In imple-
mentation, each MMX register is aliased to a

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corresponding floating-point register. MMX
technology is a recent addition to the Intel
Pentium architecture.

MNOS

acronym for metal-nitride-oxide-

si. A structure used in a type of nonvolatile
memory device in which the oxide is suffi-
ciently thin to permit electron/hole tunneling
while the nitride and the nitrode/oxide inter-
face are used to store charge.

mobile data terminal (MDT)

a computer

terminal installed in a service vehicle which,
through some wireless link, communicates
work order information between the crews
and their dispatch center.

mobile station

that part of a radio commu-

nications system, which is not permanently
located in a given geographical location.

mobile charge

the charge due to the free

electrons and holes.

mobile ion

a charged ionic species that

is mobile in a dielectric. In metal-oxide-si
(MOS) devices, Na

is most often the source

of the mobile ions.

mobile robot

a wheeled mobile robot is

a wheeled vehicle which is capable of an
autonomous motion because it is equipped
for its motion, with actuators that are driven
by an on-board computer. Therefore mobile
robot does not have an external human driver
and is completely autonomous.

mobility

electron mobility

= (2LK)/

W) where

= capacitance per unit area of the

gate-to-channel capacitor for which the ox-
ide layer serves as a dielectric.

L = length of the channel
W = width of the channel
µ

= the mobility of the electrons in the

induced

n channel

K = constant.

proton mobility

∼

= µ

/2.

MOCVD

See

metal-organic chemical

vapor deposition

modal analysis

the decomposition of a

solution to an electromagnetic analysis prob-
lem into a linear combination (weighted sum)
of elementary functions called modes. The
elementary functions are usually orthogonal;
typical functions used include sine and cosine
functions for problems cast in rectangular co-
ordinates, Bessel functions for cylindrical co-
ordinates, and spherical Bessel functions for
spherical coordinates.

This technique can be used in order to find

the field produced by an arbitrary source in-
side a waveguide, be it open or closed, or
to find the scattering matrix relative to the
discontinuity between different waveguides.
See also

eigenfunction expansion

modal expansion

See

modal analysis

modal solution

See

modal analysis

modality

(1) a part of a computer’s in-

struction that specifies how another part of
the instruction is interpreted.

(2) a specific medical imaging technique,

such as X-ray CT, magnetic resonance imag-
ing, or ultrasound, that is used to acquire an
image data set.

modality-specific

a task that is specific to

a single sense or movement pattern.

mode

(1) one possible wave solution of

an infinite number of time–harmonic wave
solutions that exist in a waveguide or trans-
mission line. Each mode is identified by a
collection of numbers and is usually desig-
nated in electromagnetics as either transverse
electric, transverse magnetic, or transverse
electromagnetic.

(2) electromagnetic field distributions that

match the boundary conditions imposed by a
laser or other cavity.

See also

2000 by CRC Press LLC

mode chart

a graphical illustration of

the variation of effective refractive index (or
equivalently, propagation angle

θ) with nor-

malized thickness

d/λ for a slab waveguide

or normalized frequency

V for an optical

fiber.

mode field radius

the radius at which the

electric field in a single mode fiber falls to
1

/e of its value at the center of the core.

mode filter

a filter that takes the mode of

the distribution containing the various input
signal components or, in the case of an image,
the mode of the distribution of all the pixel
intensity values within the neighborhood of
the current pixel. Complications can arise
from the sparsity of the local pixel intensity
distribution, and the mode should be that of
the underlying rather than the actual intensity
distribution.

mode matching

a particular type of modal

analysis referred to the analysis of a junc-
tion between different waveguides, where the
modal expansion on one side of the junction
is matched to the modal expansion on the
other side of the junction.

mode-locking

forcing the modes of a

laser oscillator to be equally spaced in fre-
quency and have a fixed phase relationship;
sometimes also occurs spontaneously. See
also

longitudinal modelocking

transverse

mode-locking

model based image coding

(1) image

compression using stored models of known
objects at both encoder and decoder, the en-
coder using computer vision techniques to
analyze incoming images in terms of the
models, and the decoder using computer
graphics techniques to re-synthesize images
from the models. The transmitted data are
model parameters that describe at a relatively
high level, the motion of the model parts. For
example, if the stored model is of a human
head, the transmitted data may be muscle
flexions.

(2) the appreciation that all image coding

relies on some model of the source, and the
categorization of methods according to the
type of model. In this scheme, definition 1 is
termed “known-object coding” or “semantic
coding.”

model reference control

the control

scheme in which the controlled system is
made to mimic the behavior of a reference
model system that possesses ideal behavioral
characteristics.

model-based predictive control

See

predictive control

modeling

the process of creating a suit-

able description that emulates the perfor-
mance or characteristics of the actual item
being modeled, over some portion of the de-
vice hyperspace. Modeling involves all or
parts of model creation, device characteri-
zation, de-embedding, parameter extraction,
verification, validation, valuation and docu-
mentation. See also

mathematical modeling

fuzzy modeling

modem

abbreviation for modulator-

demodulator. A device containing a modula-
tor and a demodulator. The modulator con-
verts a binary stream into a form suitable for
transmission over an analog medium such as
telephone wires or (in the case of a wireless
modem) air. The demodulator performs the
reverse operation, so two modems connected
via an analog channel can be used to transfer
binary data over the (analog) channel.

modem-FEC coding

error control coding

(ECC), applied to a digital signal such that
feedforward error correction (FEC), can be
used in the modem, thus detecting and often
correcting transmission errors.

moderator

a material contained in a nu-

clear reactor core which slows down neu-
trons to thermal energies, primarily by neu-
tron scattering.

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MODFET

acronym for modulation

doped FET. See

high electron mobility

transistor

modified nodal formulation

a modifica-

tion of the classical nodal formulation which
allows any network to be described.

The

modification consists of adding extra equa-
tions and unknowns when an element not nor-
mally modeled in classical nodal analysis is
encountered.

modified signed-digit computing

a com-

puting scheme in which a number is repre-
sented by modified signed-digit. This num-
ber system offers carry free addition and sub-
traction. Instead of 0 and 1, numbers are rep-
resented by

−1, 0, and 1 for the same radix

2. If a number is represented by 0 and 1,
we may need carry in the addition. However,
since the number can be represented by three
possibilities

−1, 0, and 1, the addition and

subtraction can be directly performed with-
out carry following a specific trinary logic
truth table for this number system.

modified z-transform

a z-transform of

signals and systems that contain nonzero
deadtime

τ in the range

≤ τ < T

where

T is the sampling interval. Modi-

fied z-transforms are usually derived from
fundamental principles and given as separate
columns in z-transform tables for standard
functions.

modified-return-to-bias recording

See

magnetic recording code

modifier

an operation that modifies the

membership of a fuzzy set.

Examples of

modifiers are

1. very

A = µ

con(A)

(u) = (µ

(u))

(con-

centration);

2. more or less

A = µ

dil(A)

(u) =

(µ

(u))

(dilatation).

See also

fuzzy set

linguistic variable

modular network

a network whose over-

all computation is carried out by subnetworks
whose outputs are combined in some appro-
priate way.

The term is most commonly

applied to networks that partition the input
space so that the subnetworks operate on “lo-
cal” data, but is also applied to the case where
a problem can be decomposed into successive
tasks, each being implemented by a suitable
subnetwork.

modularity

design principle that calls

for design of small, self-contained unit that
should lead to maintainability.

modulated filter bank

a filter bank ob-

tained by shifting the spectrum of a proto-
type low pass filter in the frequency domain
to cover the entire frequency band. Different
properties can be obtained by using differ-
ent modulation schemes and imposing other
conditions. Cosine-modulated filter banks
are the most commonly used modulated filter
banks.

modulating signal

the baseband source

signal used to encode information onto a car-
rier wave by varying one or more of its char-
acteristics (e.g., the amplitude, frequency, or
phase of a sinusoid; or the amplitude, width,
repetition rate, or position of each pulse in a
periodic pulse train).

modulation

(1) variation of the amplitude

or phase of an electromagnetic wave.

(2) the process of encoding an information-

carrying waveform onto a carrier wave-
form, typically in preparation for transmis-
sion. See

modulation efficiency

ratio of the base-

band bit rate to the transmission bandwidth
after modulation.

modulation index

for an angle-modulated

signal, the modulation index is the ratio of the
maximum modulation deviation to the mod-
ulating frequency, and represents the maxi-

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