WebCPC CPC COOPERATIVE PATENT CLASSIFICATION

H03G　CONTROL OF AMPLIFICATION (impedance networks, e.g. attenuators, H03H; control of transmission in lines H04B 3/04)

H03G 1/00 Details of arrangements for controlling amplification {for arrangements combined with means for generating a controlling signal, or these means per se, see the other main groups of H03G}

H03G 1/0005 ・{Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal}

H03G 1/0011 ・・{the device being at least one of the amplifying tubes of the amplifier}

H03G 1/0017 ・・{the device being at least one of the amplifying solid state elements of the amplifier}

H03G 1/0023 ・・・{in emitter-coupled or cascode amplifiers (H03GB4F takes precedence)}

H03G 1/0029 ・・・{using FETs}

H03G 1/0035 ・・{using continuously variable impedance elements}

H03G 1/0041 ・・・{using thermistors}

H03G 1/0047 ・・・{using photo-electric elements}

H03G 1/0052 ・・・{using diodes}

H03G 1/0058 ・・・・{PIN-diodes}

H03G 1/0064 ・・・・{Variable capacitance diodes}

H03G 1/007 ・・・{using FET type devices}

H03G 1/0076 ・・・{using galvanomagnetic elements}

H03G 1/0082 ・・・{using bipolar transistor-type devices}

H03G 1/0088 ・・{using discontinuously variable devices, e.g. switch-operated}

H03G 1/0094 ・・・{using switched capacitors}

H03G 1/02 ・Remote control of amplification, tone, or bandwidth (remote control in general G05, G08; combined with remote tuning or selection of resonant circuits H03J)

H03G 1/04 ・Modifications of control circuit to reduce distortion caused by control (modifications to reduce influence of variations of internal impedance of amplifying elements caused by control H03F 1/08)

H03G 3/00 Gain control in amplifiers or frequency changers {without distortion of the input signal}(gated amplifiers H03F 3/72; peculiar to television receivers H04N)

H03G 3/001 ・{Digital control of analog signals}

H03G 3/002 ・{Control of digital or coded signals (H03G 3/3089 take precedence)}

H03G 3/004 ・{Control by varying the supply voltage}

H03G 3/005 ・{Control by a pilot signal (H03G 3/001 takes precedence)}

H03G 3/007 ・{Control dependent on the supply voltage}

H03G 3/008 ・{Control by switched capacitors}

H03G 3/02 ・Manually-operated control {H03G 3/001 and H03G 3/002 take precedence}

H03G 3/04 ・・in untuned amplifiers

H03G 3/06 ・・・having discharge tubes

H03G 3/08 ・・・・incorporating negative feedback

H03G 3/10 ・・・having semiconductor devices

H03G 3/12 ・・・・incorporating negative feedback

H03G 3/14 ・・in frequency-selective amplifiers

H03G 3/16 ・・・having discharge tubes

H03G 3/18 ・・・having semiconductor devices

H03G 3/20 ・Automatic control ({H03G 3/005 takes precedence}; combined with volume compression or expansion H03G 7/00)

H03G 3/22 ・・in amplifiers having discharge tubes

H03G 3/225 ・・・{controlling or controlled by the (local) oscillators of a (super)heterodyne receiver}

H03G 3/24 ・・・Control dependent upon ambient noise level or sound level

H03G 3/26 ・・・Muting amplifier when no signal is present {or when only weak signals are present, or caused by the presence of noise, e.g. squelch systems}

H03G 3/28 ・・・・in frequency-modulation receivers; {in angle-modulation receivers}

H03G 3/30 ・・in amplifiers having semiconductor devices

H03G 3/3005 ・・・{in amplifiers suitable for low-frequencies, e.g. audio amplifiers (H03G 3/32, H03G 3/34 take precedence)}

H03G 3/301 ・・・・{the gain being continuously variable}

H03G 3/3015 ・・・・・{using diodes or transistors}

H03G 3/3021 ・・・・・{by varying the duty cycle}

H03G 3/3026 ・・・・{the gain being discontinuously variable, e.g. controlled by switching}

H03G 3/3031 ・・・・・{using switched capacitors}

H03G 3/3036 ・・・{in high-frequency amplifiers or in frequency-changers (H03G 3/3052, H03G 3/32, H03G 3/34 take precedence)}

H03G 3/3042 ・・・・{in modulators, frequency-changers, transmitters or power amplifiers ( transmission power control in bidirectional transmission systems H04W 52/04)}

H03G 3/3047 ・・・・・{for intermittent signals, e.g. burst signals}

H03G 3/3052 ・・・{in bandpass amplifiers (H.F. or I.F.) or in frequency-changers used in a (super)heterodyne receiver (H03G 3/32, H03G 3/34 take precedence)}

H03G 3/3057 ・・・・{using at least one diode as controlling device}

H03G 3/3063 ・・・・{using at least one transistor as controlling device, the transistor being used as a variable impedance device}

H03G 3/3068 ・・・・{Circuits generating control signals for both R.F. and I.F. stages}

H03G 3/3073 ・・・・{Circuits generating control signals when no carrier is present, or in SSB, CW or pulse receivers}

H03G 3/3078 ・・・・{Circuits generating control signals for digitally modulated signals}

H03G 3/3084 ・・・{in receivers or transmitters for electromagnetic waves other than radiowaves, e.g. lightwaves (H03G 3/32, H03G 3/34 take precedence)}

H03G 3/3089 ・・・{Control of digital or coded signals}

H03G 3/3094 ・・・{in parametric amplifiers (H03G 3/32, H03G 3/34 take precedence)}

H03G 3/32 ・・・the control being dependent upon ambient noise level or sound level

H03G 3/34 ・・・Muting amplifier when no signal is present {or when only weak signals are present, or caused by the presence of noise signals, e.g. squelch systems}

H03G 3/341 ・・・・{Muting when no signals or only weak signals are present (H03G 3/344, H03G 3/345 take precedence)}

H03G 3/342 ・・・・{Muting when some special characteristic of the signal is sensed which distinguishes it from noise, e.g. using speech detector (H03G 3/344, H03G 3/345 take precedence)}

H03G 3/344 ・・・・{Muting responsive to the amount of noise (noise squelch)(H03G 3/345 takes precedence)}

H03G 3/345 ・・・・{Muting during a short period of time when noise pulses are detected, i.e. blanking (H03G 3/348 takes precedence)}

H03G 3/347 ・・・・・{dependent on the rate of noise pulses}

H03G 3/348 ・・・・{Muting in response to a mechanical action or to power supply variations, e.g. during tuning; Click removal circuits}

H03G 5/00 Tone control or bandwidth control in amplifiers

H03G 5/005 ・{of digital signals (see provisionally also H03G 5/00)}

H03G 5/02 ・Manually-operated control (variable bandpass or bandstop filters H03H 7/12)

H03G 5/025 ・・{Equalizers; Volume or gain control in limited frequency bands}

H03G 5/04 ・・in untuned amplifiers

H03G 5/06 ・・・having discharge tubes

H03G 5/08 ・・・・incorporating negative feedback

H03G 5/10 ・・・having semiconductor devices

H03G 5/12 ・・・・incorporating negative feedback

H03G 5/14 ・・in frequency-selective amplifiers

H03G 5/16 ・Automatic control

H03G 5/165 ・・{Equalizers; Volume or gain control in limited frequency bands}

H03G 5/18 ・・in untuned amplifiers

H03G 5/20 ・・・having discharge tubes

H03G 5/22 ・・・having semiconductor devices

H03G 5/24 ・・in frequency-selective amplifiers

H03G 5/26 ・・・having discharge tubes

H03G 5/28 ・・・having semiconductor devices

H03G 7/00 Volume compression or expansion in amplifiers {frequency dependent H03G 9/00}

H03G 7/001 ・{without controlling loop (H03G 7/007, H03G 7/02, H03G 7/06 take precedence)}

H03G 7/002 ・{in untuned or low-frequency amplifiers e.g. audio amplifiers (H03G 7/007, H03G 7/001, H03G 7/008, H03G 7/02, H03G 7/06 take precedence)}

H03G 7/004 ・・{using continuously variable impedance devices}

H03G 7/005 ・・{using discontinuously variable devices, e.g. switch-operated}

H03G 7/007 ・{of digital or coded signals (see provis. also H03G 7/00)}

H03G 7/008 ・{Control by a pilot signal (H03G 7/007, H03G 7/02, H03G 7/06 take precedence)}

H03G 7/02 ・having discharge tubes

H03G 7/04 ・・incorporating negative feedback

H03G 7/06 ・having semiconductor devices

H03G 7/08 ・・incorporating negative feedback

H03G 9/00 Combinations of two or more types of control, e.g. gain control and tone control

H03G 9/005 ・{of digital or coded signals}

H03G 9/02 ・in untuned amplifiers (combined tone controls for low and high frequencies H03G 5/00){compression or expansion combined with volume control H03G 7/00}

H03G 9/025 ・・{frequency-dependent volume compression or expansion, e.g. multiple-band systems (H03G 9/10, H03G 9/18 take precedence)}

H03G 9/04 ・・having discharge tubes

H03G 9/06 ・・・for gain control and tone control

H03G 9/08 ・・・・incorporating negative feedback

H03G 9/10 ・・・for tone control and volume expansion or compression

H03G 9/12 ・・having semiconductor devices

H03G 9/14 ・・・for gain control and tone control

H03G 9/16 ・・・・incorporating negative feedback

H03G 9/18 ・・・for tone control and volume expansion or compression

H03G 9/20 ・in frequency-selective amplifiers

H03G 9/22 ・・having discharge tubes

H03G 9/24 ・・having semiconductor devices

H03G 9/26 ・in untuned amplifying stages as well as in frequency-selective amplifying stages (gain control in both stages H03G 3/00; tone control or bandwidth control H03G 5/00){compression or expansion combined with volume control H03G 7/00}

H03G 9/28 ・・all amplifying stages having discharge tubes

H03G 9/30 ・・all amplifying stages having semiconductor devices

H03G 11/00 Limiting amplitude; Limiting rate of change of amplitude; {Clipping in general}

H03G 11/002 ・{without controlling loop (H03G 11/004, H03G 11/006, H03G 11/008, H03G 11/02, H03G 11/04, H03G 11/06, H03G 11/08 take precedence; see provisional also H03G 11/00)}

H03G 11/004 ・{using discharge tubes (H03G 11/008 takes precedence)}

H03G 11/006 ・{in circuits having distributed constants (H03G 11/008 takes precedence)}

H03G 11/008 ・{of digital or coded signals (see provis. also H03G 11/00, H03G 11/02)}

H03G 11/02 ・by means of diodes ({H03G 11/008,}H03G 11/04, H03G 11/06, H03G 11/08 take precedence)

H03G 11/025 ・・{in circuits having distributed constants}

H03G 11/04 ・Limiting level dependent on strength of signal; Limiting level dependent on strength of carrier on which signal is modulated {H03G 11/008 takes precedence}

H03G 11/06 ・Limiters of angle-modulated signals; such limiters combined with discriminators ([N:H03G 11/00 takes precedence; discriminators having an inherent limiting action H03D 3/00)

H03G 11/08 ・Limiting rate of change of amplitude {H03G 11/008 takes precedence}

H03G 99/00 Subject matter not provided for in other groups of this subclass

H03G 2201/00 Indexing scheme relating to subclass H03G

H03G 2201/10 ・Gain control characterised by the type of controlled element

H03G 2201/103 ・・being an amplifying element

H03G 2201/106 ・・being attenuating element

H03G 2201/20 ・Gain control characterized by the position of the detection

H03G 2201/202 ・・being in baseband

H03G 2201/204 ・・being in intermediate frequency

H03G 2201/206 ・・being in radio frequency

H03G 2201/208 ・・being in power supply of the amplifier

H03G 2201/30 ・Gain control characterized by the type of controlled signal

H03G 2201/302 ・・being baseband signal

H03G 2201/305 ・・being intermediate frequency signal

H03G 2201/307 ・・being radio frequency signal

H03G 2201/40 ・Combined gain and bias control

H03G 2201/50 ・Gain control characterized by the means of gain control

H03G 2201/502 ・・by switching impedance in feedback loop

H03G 2201/504 ・・by summing selected parallel amplifying paths, i.e. more amplifying/attenuating paths summed together

H03G 2201/506 ・・by selecting one parallel amplifying path

H03G 2201/508 ・・by using look-up tables

H03G 2201/60 ・Gain control characterized by varying time constants in control loop

H03G 2201/603 ・・time constant being continuous

H03G 2201/606 ・・time constant being discrete

H03G 2201/70 ・Gain control characterized by the gain control parameter

H03G 2201/702 ・・being frequency, e.g. frequency deviations

H03G 2201/704 ・・being number of multiplexed channels

H03G 2201/706 ・・being quality indicator, e.g. BER,C/I

H03G 2201/708 ・・being temperature