H03DDEMODULATION 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 H03K9/00; transforming types of pulse modulation H03K11/00; coding, decoding or code conversion, in general H03M; repeater stations H04B7/14; demodulators adapted for ac systems of digital information transmission H04L27/00; synchronous demodulators adapted for colour television H04N9/66This 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.In this subclass non-limiting references (in the sense of paragraph 39 of the Guide to the IPC) may still be displayed in the scheme. H03D1/00 H03D1/00Demodulation of amplitude-modulated oscillations H03D5/00, H03D9/00, H03D11/00 take precedence H03D1/02Details H03D1/04Modifications of demodulators to reduce interference by undesired signals H03D1/06Modifications of demodulators to reduce distortion, e.g. by negative feedback H03D1/08by means of non-linear two-pole elements H03D1/22, H03D1/26, H03D1/28 take precedence H03D1/10of diodes H03D1/12with provision for equalising ac and dc loads H03D1/14by means of non-linear elements having more than two poles H03D1/22, H03D1/26, H03D1/28 take precedence H03D1/16of discharge tubes H03D1/18of semiconductor devices H03D1/20with provision for preventing undesired type of demodulation, e.g. preventing anode detection in a grid detection circuit H03D1/22Homodyne or synchrodyne circuits receiver circuits H04B1/30 H03D1/2209Decoders 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 H03D1/2218using diodes for the decoding H03D1/2227using switches for the decoding diodes used as switches H03D1/2218 H03D1/2236using a phase locked loop H03D1/2245using two quadrature channels H03D1/2209 takes precedence H03D1/2254and a phase locked loop H03D2001/2263including a counter or a divider in the PLL H03D1/2272using FET's H03D1/2209, H03D1/2245 and H03D1/2281 take precedence H03D1/2281using a phase locked loop H03D1/2236 and H03D1/2254 take precedence H03D1/229using at least a two emittor-coupled differential pair of transistors H03D1/2209 - H03D1/2281 take precedence H03D1/24for demodulation of signals wherein one sideband or the carrier has been wholly or partially suppressed receiver circuits H04B1/302 H03D1/26by means of transit-time tubes H03D1/28by deflecting an electron beam in a discharge tube H03D1/26 takes precedence H03D3/00Demodulation of angle-, frequency- or phase- modulated oscillations H03D5/00, H03D9/00, H03D11/00 take precedence H03D3/001Details of arrangements applicable to more than one type of frequency demodulator H03D3/28 takes precedence H03D3/002Modifications of demodulators to reduce interference by undesired signals H03D3/248 takes precedence H03D3/003Arrangements for reducing frequency deviation, e.g. by negative frequency feedback combined with a phase locked loop demodulator H03D3/242; changing frequency deviation for modulators H03C3/06 H03D3/004wherein the demodulated signal is used for controlling an oscillator, e.g. the local oscillator H03D3/005wherein the demodulated signal is used for controlling a bandpass filter automatic bandwidth control H03G; automatic frequency control H03J7/02 H03D3/006by sampling the oscillations and further processing the samples, e.g. by computing techniques H03D3/007 takes precedence H03D3/007by converting the oscillations into two quadrature related signals H03D3/245 takes precedence H03D3/008Compensating DC offsets H03D3/009Compensating quadrature phase or amplitude imbalances H03D3/02by detecting phase difference between two signals obtained from input signal H03D3/28 - H03D3/32 take precedence; muting in frequency-modulation receivers H03G3/28; limiting arrangements H03G11/00 H03D3/04by counting or integrating cycles of oscillations arrangements for measuring frequencies G01R23/10 H03D3/06by combining signals additively or in product demodulators H03D3/08by means of diodes, e.g. Foster-Seeley discriminator H03D3/10in which the diodes are simultaneously conducting during the same half period of the signal, e.g. radio detector H03D3/12by means of discharge tubes having more than two electrodes H03D3/14by means of semiconductor devices having more than two electrodes H03D3/16by means of electromechanical resonators H03D3/18by means of synchronous gating arrangements H03D3/20producing pulses whose amplitude or duration depends on phase difference H03D3/22by 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 H03D3/24Modifications of demodulators to reject or remove amplitude variations by means of locked-in oscillator circuits H03D3/241the oscillator being part of a phase locked loop H03D3/242combined with means for controlling the frequency of a further oscillator, e.g. for negative frequency feedback or AFC H03D3/244combined with means for obtaining automatic gain control H03D3/245using at least twophase detectors in the loop H03D3/244 takes precedence; in general H03L7/087 H03D3/247using a controlled phase shifter in general H03L7/081 H03D3/248with means for eliminating interfering signals, e.g. by multiple phase locked loops multiple loops in general H03L7/07, H03L7/22 H03D3/26by means of sloping amplitude/frequency characteristic of tuned or reactive circuit H03D3/28 - H03D3/32 takes precedence H03D3/28Modifications of demodulators to reduce effects of temperature variations automatic frequency regulation in receivers H03J; automatic frequency control H03L H03D3/30by means of transit-time tubes H03D3/32by deflecting an electron beam in a discharge tube H03D3/30 takes precedence H03D3/34by means of electromechanical devices H03D3/16 takes precedence H03D5/00Circuits for demodulating amplitude-modulated or angle-modulated oscillations at will H03D9/00, H03D11/00 take precedence H03D7/00Transference of modulation from one carrier to another, e.g. frequency-changing H03D9/00, H03D11/00 take precedence; dielectric amplifiers, magnetic amplifiers, parametric amplifiers used as a frequency-changers H03F H03D7/005by means of superconductive devices H03D7/02by means of diodes H03D7/14 - H03D7/22 take precedence H03D7/04having a partially negative resistance characteristic, e.g. tunnel diode H03D7/06by means of discharge tubes having more than two electrodes H03D7/14 - H03D7/22 take precedence H03D7/08the signals to be mixed being applied between the same two electrodes H03D7/10the signals to be mixed being applied between different pairs of electrodes H03D7/12by means of semiconductor devices having more than two electrodes H03D7/14 - H03D7/22 take precedence H03D7/125with field effect transistors H03D7/14Balanced arrangements H03D7/1408with diodes H03D7/1416with discharge tubes having more than two electrodes H03D7/1425with transistors H03D7/1433using bipolar transistors H03D7/145 takes precedence H03D7/1441using field-effect transistors H03D7/145 takes precedence H03D7/145using a combination of bipolar transistors and field-effect transistors H03D7/1458Double balanced arrangements, i.e. where both input signals are differential H03D7/1466Passive mixer arrangements H03D7/1475Subharmonic mixer arrangements H03D7/1483comprising components for selecting a particular frequency component of the output H03D7/1491Arrangements to linearise a transconductance stage of a mixer arrangement H03D7/16Multiple-frequency-changing H03D7/161all the frequency changers being connected in cascade H03D7/163the local oscillations of at least two of the frequency changers being derived from a single oscillator H03D7/165at least two frequency changers being located in different paths, e.g. in two paths with carriers in quadrature combined with amplitude demodulation H03D1/2245, combined with angle demodulation H03D3/007; N-path filters H03H19/002 H03D7/166using two or more quadrature frequency translation stages H03D7/168using a feedback loop containing mixers or demodulators H03D7/18Modifications of frequency-changers for eliminating image frequencies H03D7/16 takes precedence H03D7/20by means of transit-time tubes H03D7/22by deflecting an electron beam in a discharge tube H03D7/20 takes precedence H03D9/00Demodulation or transference of modulation of modulated electromagnetic waves demodulating light, transferring modulation in light waves G02F2/00 H03D9/02Demodulation using distributed inductance and capacitance, e.g. in feeder lines H03D9/04for angle-modulated oscillations H03D9/06Transference of modulation using distributed inductance and capacitance H03D9/0608by means of diodes H03D9/0616mounted in a hollow waveguide H03D9/0641 takes precedence H03D9/0625mounted in a coaxial resonator structure H03D9/0633mounted on a stripline circuit H03D9/0641located in a hollow waveguide H03D9/065by means of discharge tubes having more than two electrodes H03D9/0658by means of semiconductor devices having more than two electrodes H03D9/0666using bipolar transistors H03D9/0683 takes precedence H03D9/0675using field effect transistors H03D9/0683 takes precedence H03D9/0683using a combination of bipolar transistors and field effect transistors H03D2009/0691by means of superconductive devices H03D11/00Super-regenerative demodulator circuits applications in responders G01S H03D11/02for amplitude-modulated oscillations H03D11/04by means of semiconductor devices having more than two electrodes H03D11/06for angle-modulated oscillations H03D11/08by means of semiconductor devices having more than two electrodes H03D13/00Circuits for comparing the phase or frequency of two mutually-independent oscillations measuring phase G01R25/00; phase-discriminators with yes/no output G01R25/005 H03D13/001in which a pulse counter is used followed by a conversion into an analog signal H03D13/002the counter being an up-down counter H03D13/003in which both oscillations are converted by logic means into pulses which are applied to filtering or integrating means H03D13/004the logic means delivering pulses at more than one terminal, e.g. up and down pulses H03D13/005in which one of the oscillations is, or is converted into, a signal having a special waveform, e.g. triangular H03D13/006and by sampling this signal by narrow pulses obtained from the second oscillation H03D13/007by analog multiplication of the oscillations or by performing a similar analog operation on the oscillations H03D13/008using transistors H03D13/009using diodes H03D99/00Subject matter not provided for in other groups of this subclass H03D2200/00 H03D2200/00Indexing scheme relating to details of demodulation or transference of modulation from one carrier to another covered by H03D H03D2200/0001Circuit elements of demodulators H03D2200/0003Rat race couplers H03D2200/0005Wilkinson power dividers or combiners H03D2200/0007Dual gate field effect transistors H03D2200/0009Emitter or source coupled transistor pairs or long tail pairs H03D2200/0011Diodes H03D2200/0013Diodes connected in a ring configuration H03D2200/0015Diodes connected in a star configuration H03D2200/0017Intermediate frequency filter H03D2200/0019Gilbert multipliers H03D2200/0021Frequency multipliers H03D2200/0023Balun circuits H03D2200/0025Gain control circuits H03D2200/0027including arrangements for assuring the same gain in two paths H03D2200/0029Loop circuits with controlled phase shift H03D2200/0031PLL circuits with quadrature locking, e.g. a Costas loop H03D2200/0033Current mirrors H03D2200/0035Digital multipliers and adders used for detection H03D2200/0037Diplexers H03D2200/0039Exclusive OR logic circuits H03D2200/0041Functional aspects of demodulators H03D2200/0043Bias and operating point H03D2200/0045Calibration of demodulators H03D2200/0047Offset of DC voltage or frequency H03D2200/0049Analog multiplication for detection H03D2200/005Analog to digital conversion H03D2200/0052Digital to analog conversion H03D2200/0054Digital filters H03D2200/0056including a digital decimation filter H03D2200/0058using a digital filter with interpolation H03D2200/006Signal sampling H03D2200/0062Computation of input samples, e.g. successive samples H03D2200/0064Detection of passages through null of a signal H03D2200/0066Mixing H03D2200/0068by computation H03D2200/007by using a logic circuit, e.g. flipflop, XOR H03D2200/0072by complex multiplication H03D2200/0074using a resistive mixer or a passive mixer H03D2200/0076using a distributed mixer H03D2200/0078using a switched phase shifter or delay line H03D2200/008Hilbert type transformation H03D2200/0082Quadrature arrangements H03D2200/0084Lowering the supply voltage and saving power H03D2200/0086Reduction or prevention of harmonic frequencies H03D2200/0088Reduction of intermodulation, nonlinearities, adjacent channel interferenceintercept points of harmonics or intermodulation products H03D2200/009Reduction of local oscillator or RF leakage H03D2200/0092Detection or reduction of fading in multipath transmission arrangements H03D2200/0094Measures to address temperature induced variations of demodulation H03D2200/0096by stabilising the temperature H03D2200/0098by compensating temperature induced variations