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Outline
Indent Level
Color Curly Brackets (indicating CPC extensions to IPC)

CPC
COOPERATIVE PATENT CLASSIFICATION
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DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER (masers, lasers H01S; circuits capable of acting both as modulator and demodulator H03C; details applicable to both modulators and frequency-changers H03C; demodulating pulses H03K 9/00; transforming types of pulse modulation H03K 11/00; coding, decoding or code conversion, in general H03M; repeater stations H04B 7/14; demodulators adapted for ac systems of digital information transmission H04L 27/00; synchronous demodulators adapted for colour television H04N 9/66)
NOTE
-
This subclass covers only:

- demodulation or transference of signals modulated on a
sinusoidal carrier or on electromagnetic waves;
- comparing phase or frequency of two mutually-independent
oscillations.

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Demodulation of amplitude-modulated oscillations (H03D 5/00, H03D 9/00, H03D 11/00 take precedence)
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H03D 1/02
.
Details
. .
Modifications of demodulators to reduce interference by undesired signals
H03D 1/06
. .
Modifications of demodulators to reduce distortion, e.g. by negative feedback
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.
by means of non-linear two-pole elements (H03D 1/22, H03D 1/26, H03D 1/28 take precedence)
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H03D 1/10
. .
of diodes
H03D 1/12
. . .
with provision for equalising ac and dc loads
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.
by means of non-linear elements having more than two poles (H03D 1/22, H03D 1/26, H03D 1/28 take precedence)
H03D 1/16
. .
of discharge tubes
. .
of semiconductor devices
H03D 1/20
. .
with provision for preventing undesired type of demodulation, e.g. preventing anode detection in a grid detection circuit
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.
Homodyne or synchrodyne circuits
{
(receiver circuits H04B 1/30)
}
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H03D 1/2209
. .
{
Decoders for simultaneous demodulation and decoding of signals composed of a sum-signal and a suppressed carrier, amplitude modulated by a difference signal, e.g. stereocoders
}
H03D 1/2218
. . .
{
using diodes for the decoding
}
. . .
{
using switches for the decoding (diodes used as switches H03D 1/2218)
}
H03D 1/2236
. . .
{
using a phase locked loop
}
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. .
{
using two quadrature channels (H03D 1/2209 takes precedence)
}
. . .
{
and a phase locked loop
}
. .
{
using FET`s (H03D 1/2209, H03D 1/2245 and H03D 1/2281 take precedence)
}
H03D 1/2281
. .
{
using a phase locked loop (H03D 1/2236 and H03D 1/2254 take precedence)
}
H03D 1/229
. .
{
using at least a two emittor-coupled differential pair of transistors (H03D 1/2209 to H03D 1/2281 take precedence)
}
. .
for demodulation of signals wherein one sideband or the carrier has been wholly or partially suppressed
{
(receiver circuits H04B 1/302)
}
H03D 1/26
.
by means of transit-time tubes
.
by deflecting an electron beam in a discharge tube (H03D 1/26 takes precedence)
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Demodulation of angle-,
{
frequency- or phase-
}
modulated oscillations (H03D 5/00, H03D 9/00, H03D 11/00 take precedence)
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.
{
Details of arrangements applicable to more than one type of frequency demodulator (H03D 3/28 takes precedence)
}
. .
{
Modifications of demodulators to reduce interference by undesired signals (H03D 3/248 takes precedence)
}
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. .
{
Arrangements for reducing frequency deviation, e.g. by negative frequency feedback (combined with a phase locked loop demodulator H03D 3/242; changing frequency deviation for modulators H03C 3/06)
}
H03D 3/004
. . .
{
wherein the demodulated signal is used for controlling an oscillator, e.g. the local oscillator
}
. . .
{
wherein the demodulated signal is used for controlling a bandpass filter (automatic bandwidth control H03G; automatic frequency control H03J 7/02)
}
.
{
by sampling the oscillations and further processing the samples, e.g. by computing techniques (H03D 3/007 takes precedence)
}
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.
{
by converting the oscillations into two quadrature related signals (H03D 3/245 takes precedence)
}
H03D 3/008
. .
{
Compensating DC offsets
}
H03D 3/009
. .
{
Compensating quadrature phase or amplitude imbalances
}
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.
by detecting phase difference between two signals obtained from input signal (H03D 3/28 to H03D 3/32 take precedence;
{
muting in frequency-modulation receivers H03G 3/28
}
; limiting arrangements H03G 11/00)
. .
by counting or integrating cycles of oscillations
{
arrangements for measuring frequencies G01R 23/10
}
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H03D 3/06
. .
by combining signals additively or in product demodulators
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H03D 3/08
. . .
by means of diodes, e.g. Foster-Seeley discriminator
H03D 3/10
. . . .
in which the diodes are simultaneously conducting during the same half period of the signal, e.g. radio detector
H03D 3/12
. . .
by means of discharge tubes having more than two electrodes
H03D 3/14
. . .
by means of semiconductor devices having more than two electrodes
H03D 3/16
. . .
by means of electromechanical resonators
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H03D 3/18
. .
by means of synchronous gating arrangements
H03D 3/20
. . .
producing pulses whose amplitude or duration depends on phase difference
H03D 3/22
. .
by means of active elements with more than two electrodes to which two signals are applied derived from the signal to be demodulated and having a phase difference related to the frequency deviation, e.g. phase detector
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H03D 3/24
. .
Modifications of demodulators to reject or remove amplitude variations by means of locked-in oscillator circuits
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H03D 3/241
. . .
{
the oscillator being part of a phase locked loop
}
H03D 3/242
. . . .
{
combined with means for controlling the frequency of a further oscillator, e.g. for negative frequency feedback or AFC
}
H03D 3/244
. . . .
{
combined with means for obtaining automatic gain control
}
. . . .
{
using at least twophase detectors in the loop (H03D 3/244 takes precedence; in general H03L 7/087)
}
. . . .
{
using a controlled phase shifter (in general H03L 7/081)
}
. . . .
{
with means for eliminating interfering signals, e.g. by multiple phase locked loops (multiple loops in general H03L 7/07, H03L 7/22)
}
.
by means of sloping amplitude/frequency characteristic of tuned or reactive circuit (H03D 3/28 to H03D 3/32 takes precedence)
.
Modifications of demodulators to reduce effects of temperature variations (
{
automatic frequency regulation in receivers H03J
}
; automatic frequency control H03L)
H03D 3/30
.
by means of transit-time tubes
.
by deflecting an electron beam in a discharge tube (H03D 3/30 takes precedence)
.
by means of electromechanical devices (H03D 3/16 takes precedence)
Circuits for demodulating amplitude-modulated or angle-modulated oscillations at will (H03D 9/00, H03D 11/00 take precedence)
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Transference of modulation from one carrier to another, e.g. frequency-changing (H03D 9/00, H03D 11/00 take precedence; dielectric amplifiers, magnetic amplifiers, parametric amplifiers used as a frequency-changers H03F)
H03D 7/005
.
{
by means of superconductive devices
}
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.
by means of diodes (H03D 7/14 to H03D 7/22 take precedence)
H03D 7/04
. .
having
{
a partially
}
negative resistance characteristic, e.g. tunnel diode
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.
by means of discharge tubes having more than two electrodes (H03D 7/14 to H03D 7/22 take precedence)
H03D 7/08
. .
the signals to be mixed being applied between the same two electrodes
H03D 7/10
. .
the signals to be mixed being applied between different pairs of electrodes
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.
by means of semiconductor devices having more than two electrodes (H03D 7/14 to H03D 7/22 take precedence)
H03D 7/125
. .
{
with field effect transistors
}
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.
Balanced arrangements
H03D 7/1408
. .
{
with diodes
}
H03D 7/1416
. .
{
with discharge tubes having more than two electrodes
}
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. .
{
with transistors
}
WARNING
-
Subgroups H03D 7/1433 to H03D 7/1491 are incomplete pending reclassification; see also this group and its other subgroups

H03D 7/1433
. . .
{
using bipolar transistors (H03D 7/145 takes precedence)
}
H03D 7/1441
. . .
{
using field-effect transistors (H03D 7/145 takes precedence)
}
H03D 7/145
. . .
{
using a combination of bipolar transistors and field-effect transistors
}
H03D 7/1458
. . .
{
Double balanced arrangements, i.e. where both input signals are differential
}
H03D 7/1466
. . .
{
Passive mixer arrangements
}
H03D 7/1475
. . .
{
Subharmonic mixer arrangements
}
H03D 7/1483
. . .
{
comprising components for selecting a particular frequency component of the output
}
H03D 7/1491
. . .
{
Arrangements to linearise a transconductance stage of a mixer arrangement
}
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.
Multiple-frequency-changing
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H03D 7/161
. .
{
all the frequency changers being connected in cascade
}
H03D 7/163
. . .
{
the local oscillations of at least two of the frequency changers being derived from a single oscillator
}
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. .
{
at least two frequency changers being located in different paths, e.g. in two paths with carriers in quadrature (combined with amplitude demodulation H03D 1/2245, combined with angle demodulation H03D 3/007; N-path filters H03H 19/002)
}
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H03D 7/166
. . .
{
using two or more quadrature frequency translation stages
}
H03D 7/168
. . . .
{
using a feedback loop containing mixers or demodulators
}
.
Modifications of frequency-changers for eliminating image frequencies
{
(H03D 7/16 takes precedence)
}
H03D 7/20
.
by means of transit-time tubes
.
by deflecting an electron beam in a discharge tube (H03D 7/20 takes precedence)
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Demodulation or transference of modulation of modulated electromagnetic waves (demodulating light, transferring modulation in light waves G02F 2/00)
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.
Demodulation using distributed inductance and capacitance, e.g. in feeder lines
H03D 9/04
. .
for angle-modulated oscillations
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.
Transference of modulation using distributed inductance and capacitance
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H03D 9/0608
. .
{
by means of diodes
}
. . .
{
mounted in a hollow waveguide (H03D 9/0641 takes precedence)
}
H03D 9/0625
. . .
{
mounted in a coaxial resonator structure
}
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H03D 9/0633
. . .
{
mounted on a stripline circuit
}
H03D 9/0641
. . . .
{
located in a hollow waveguide
}
H03D 9/065
. .
{
by means of discharge tubes having more than two electrodes
}
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H03D 9/0658
. .
{
by means of semiconductor devices having more than two electrodes
}
. . .
{
using bipolar transistors (H03D 9/0683 takes precedence)
}
. . .
{
using field effect transistors (H03D 9/0683 takes precedence)
}
H03D 9/0683
. . .
{
using a combination of bipolar transistors and field effect transistors
}
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Super-regenerative demodulator circuits
{
applications in responders G01S
}
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H03D 11/02
.
for amplitude-modulated oscillations
. .
by means of semiconductor devices having more than two electrodes
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H03D 11/06
.
for angle-modulated oscillations
H03D 11/08
. .
by means of semiconductor devices having more than two electrodes
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Circuits for comparing the phase or frequency of two mutually-independant oscillations
{
(measuring phase G01R 25/00; phase-discriminators with yes/no output G01R 25/005)
}
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H03D 13/001
.
{
in which a pulse counter is used followed by a conversion into an analog signal
}
H03D 13/002
. .
{
the counter being an up-down counter
}
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H03D 13/003
.
{
in which both oscillations are converted by logic means into pulses which are applied to filtering or integrating means
}
H03D 13/004
. .
{
the logic means delivering pulses at more than one terminal, e.g. up and down pulses
}
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H03D 13/005
.
{
in which one of the oscillations is, or is converted into, a signal having a special waveform, e.g. triangular
}
H03D 13/006
. .
{
and by sampling this signal by narrow pulses obtained from the second oscillation
}
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H03D 13/007
.
{
by analog multiplication of the oscillations or by performing a similar analog operation on the oscillations
}
H03D 13/008
. .
{
using transistors
}
H03D 13/009
. .
{
using diodes
}
Subject matter not provided for in other groups of this subclass
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H03D 2001/00
Demodulation of amplitude-modulated oscillations (H03D 5/00, H03D 9/00, H03D 11/00 take precedence)
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H03D 2001/22
.
Homodyne or synchrodyne circuits
{
(receiver circuits H04B 1/30)
}
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H03D 2001/2245
. .
{
using two quadrature channels (H03D 1/2209 takes precedence)
}
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H03D 2001/2254
. . .
{
and a phase locked loop
}
H03D 2001/2263
. . . .
including a counter or a divider in the PLL
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H03D 2009/00
Demodulation or transference of modulation of modulated electromagnetic waves (demodulating light, transferring modulation in light waves G02F 2/00)
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H03D 2009/06
.
Transference of modulation using distributed inductance and capacitance
H03D 2009/0691
. .
by means of superconductive devices
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Indexing scheme relating to details of demodulation or transference of modulation from one carrier to another covered by H03D
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H03D 2200/0001
.
Circuit elements of demodulators
H03D 2200/0003
. .
Rat race couplers
H03D 2200/0005
. .
Wilkinson power dividers or combiners
H03D 2200/0007
. .
Dual gate field effect transistors
H03D 2200/0009
. .
Emitter or source coupled transistor pairs or long tail pairs
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H03D 2200/0011
. .
Diodes
H03D 2200/0013
. . .
Diodes connected in a ring configuration
H03D 2200/0015
. . .
Diodes connected in a star configuration
H03D 2200/0017
. .
Intermediate frequency filter
H03D 2200/0019
. .
Gilbert multipliers
H03D 2200/0021
. .
Frequency multipliers
H03D 2200/0023
. .
Balun circuits
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H03D 2200/0025
. .
Gain control circuits
H03D 2200/0027
. . .
including arrangements for assuring the same gain in two paths
H03D 2200/0029
. .
Loop circuits with controlled phase shift
H03D 2200/0031
. .
PLL circuits with quadrature locking, e.g. a Costas loop
H03D 2200/0033
. .
Current mirrors
H03D 2200/0035
. .
Digital multipliers and adders used for detection
H03D 2200/0037
. .
Diplexers
H03D 2200/0039
. .
Exclusive OR logic circuits
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H03D 2200/0041
.
Functional aspects of demodulators
H03D 2200/0043
. .
Bias and operating point
H03D 2200/0045
. .
Calibration of demodulators
H03D 2200/0047
. .
Offset of DC voltage or frequency
H03D 2200/0049
. .
Analog multiplication for detection
H03D 2200/005
. .
Analog to digital conversion
H03D 2200/0052
. .
Digital to analog conversion
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H03D 2200/0054
. .
Digital filters
H03D 2200/0056
. . .
including a digital decimation filter
H03D 2200/0058
. . .
using a digital filter with interpolation
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H03D 2200/006
. .
Signal sampling
H03D 2200/0062
. . .
Computation of input samples, e.g. successive samples
H03D 2200/0064
. .
Detection of passages through null of a signal
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H03D 2200/0066
. .
Mixing
H03D 2200/0068
. . .
by computation
H03D 2200/007
. . .
by using a logic circuit, e.g. flipflop, XOR
H03D 2200/0072
. . .
by complex multiplication
H03D 2200/0074
. . .
using a resistive mixer or a passive mixer
H03D 2200/0076
. . .
using a distributed mixer
H03D 2200/0078
. . .
using a switched phase shifter or delay line
H03D 2200/008
. .
Hilbert type transformation
. .
Quadrature arrangements
H03D 2200/0084
. .
Lowering the supply voltage and saving power
H03D 2200/0086
. .
Reduction or prevention of harmonic frequencies
H03D 2200/0088
. .
Reduction of intermodulation, nonlinearities, adjacent channel interference; intercept points of harmonics or intermodulation products
H03D 2200/009
. .
Reduction of local oscillator or RF leakage
H03D 2200/0092
. .
Detection or reduction of fading in multipath transmission arrangements
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H03D 2200/0094
. .
Measures to address temperature induced variations of demodulation
H03D 2200/0096
. . .
by stabilising the temperature
H03D 2200/0098
. . .
by compensating temperature induced variations
This page is owned by Office of Patent Classification.
Last Modified: 10/10/2013