Format distortion feedback (fdfb). RU patent 2289880.

FIELD: radio engineering.

SUBSTANCE: amplifier format distortion feedback (FB) consists of conversion deviation signal forming chain implemented using resistors (2,3) inserted between output and input of inverting amplifier (4), which has conversion slope control input (5). Received conversion deviation signal is multiplied by multiplier (1), whose signal adaptively defines amplifier (4) transfer characteristic slope. Such FB is adaptive non-linear, that is format distortion feedback (FDFB).

EFFECT: decreased format distortion, which occur because of amplifier voltage (current) transfer non-linearity characteristic ambiguity, and defined as product of signal frequency and its amplitude.

1 dwg

IPC classes for russian patent Format distortion feedback (fdfb). RU patent 2289880. (RU 2289880):

H03G3/20 - Automatic control (combined with volume compression or expansion H03G0007000000)

H03F1/32 - AMPLIFIERS (measuring, testing G01R; optical parametric amplifiers G02F; circuit arrangements with secondary emission tubes H01J0043300000; masers, lasers H01S; dynamo-electric amplifiers H02K; control of amplification H03G; coupling arrangements independent of the nature of the amplifier, voltage dividers H03H; amplifiers capable only of dealing with pulses H03K; repeater circuits in transmission lines H04B0003360000, H04B0003580000; application of speech amplifiers in telephonic communication H04M0001600000, H04M0003400000)

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