Page 52 - Electrical Engineering Dictionary

analyte the substance being measured by AND gate a device that implements the
a chemical or bioanalytical sensor and instru- Boolean AND operation. See AND.
mentation system.
angle diversity a diversity technique used
analytic signal refers to a signal that has a in radio communications based on receiving
Fourier transform that is zero valued for neg- a signal over multiple arrival angles. The
ative frequencies; i.e., the signal has a one- signal components are typically affected by
sided spectrum. uncorrelated fading processes and are com-
bined in the receiver to improve performance.
analytical Jacobian a mathematical rep- The main combining methods are selection
resentation computed via differentiation of diversity, equal gain combining, and maxi-
the direct kinematic equation with respect to mal ratio combining.
the joint variables q. Formally one can write
h i h i
˙ φ J φ (q)
˙ x = = ˙ q = J A (q)˙q where the angle modulation a type of modulation
˙ p J p (q)
∂k(q) where either the frequency (FM) or the phase
analytical Jacobian is J A (q) = . See
∂q (PM) of a carrier are varied.
external spacefor notation used in these equa-
tions. The analytical Jacobian is different
angle of arrival (AOA) the direction to
from the geometric Jacobian, since the end-
a source emitting a signal impinging on a
effector angular velocity with respect to the
sensor array. Also called direction of arrival
base frame is not given by ˙ φ. Both Jacobians
(DOA).
are related as J = T A (φ)J A where T A (φ) is
a matrix that depends on the particular repre-
angstrom popular unit not officially rec-
sentation of the orientation representation. In
ognized as part of the SI unit system. Equal
particular T A (φ) is an identity matrix when −10 _
to 10 meters. Abbreviated A. Named af-
equivalent axis of rotation in the task space _
ter Anders Angstr¨ om (1814–1874).
is the same as the equivalent axis of rota-
tion of the end-effector. See also geometric
angular alignment loss the optical power
Jacobian.
loss in an optical connection between two op-
tical fibers, between an optical source and a
anamorphic lenses a lens system having
fiber, or between an optical fiber and a detec-
a difference in optical magnification along
tor caused by the angular misalignment of the
the two mutually perpendicular axes (ver-
axes of the source and fiber, the two fibers,
tical plane or tilt vs. horizontal plane or
or the fiber and detector.
panorama).
angular frequency the rate of change of
and See AND.
the phase of a wave in radians per second.
AND the Boolean operator that imple-
anisotropic direction-dependent.
ments the conjunction of two predicates. The
truth table for ∧≡ X and Y is
anisotropic diffraction diffraction when
XY X ∧ Y the refractive indices for the incident and
FF F diffracted optical waves are different.
FT F
TF F anisotropic diffusion a process of pro-
TT T gressive image smoothing as a function of a
time variable t, such that the degree and ori-
n-ary ands can be obtained as conjunction of entation of smoothing at a point varies ac-
binary ands. cording to certain parameters measured at

c
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