Non-reactive limiter

Claim 2

An amplitude limiter for removing the modulation from a carrier signal amplitude modulated by a modulating signal comprising: detecting means responsive to the carrier signal for providing a replica of the modulating signal; a voltage divider including fixed resistance means and variable resistance means; means for applying the amplitude modulated carrier signal across the voltage divider; and means responsive to the detected replica of the modulating signal for linearly varying the variable resistance in accordance with the instantaneous amplitude thereof so as to develop a carrier signal across the variable resistance which is substantially free of both amplitude and angle modulation.

Claim 3

An amplitude limiter according to claim 1 wherein the variable resistance means comprises a PIN diode having a substantially linear resistance versus current characteristic.

Claim 4

An amplitude limiter according to claim 2 wherein the means for varying comprises a current generating network for establishing a current in the PIN diode for linearly varying its resistance in inverse relation to the instantaneous level of the amplitude modulated carrier signal.

Claim 5

An amplitude limiter according to claim 3 wherein the current generating network comprises first and second differentially connected transistors having their emitters connected in common to a constant current source, the base and collector of the first transistor be coupled for receiving the detected replica of the modulating signal and a DC supply potential respectively, the base and collector of the second transistor being coupled to a source of bias potential and the PIN diode respectively.

Claim 6

An amplitude limiter for removing the modulation from a carrier signal amplitude modulated by a modulating signal comprising: detecting means responsive to the carrier signal for providing a replica of the modulating signal; a voltage divider including a fixed resistance and a PIN diode having a substantially linear resistance versus current characteristic above a given frequency; means for applying the amplitude modulated carrier signal across the voltage divider; and current generating means responsive to the detected replica of the modulating signal for establishing a current in the PIN diode for linearly varying its resistance in inverse relation to the instantaneous level of the modulating signal so as to develop a carrier signal across the PIN diode which is substantially free of both amplitude and angle modulation.

Claim 7

An amplitude limiter for removing the modulation from a carrier signal amplitude modulated by a modulating signal comprising: detecting means responsive to the carrier signal for providing a replica of the modulating signal; a voltage divider including a fixed resistance and a PIN diode having a substantially linear resistance versus current characteristic above a given frequency; means for applying the amplitude modulated carrier signal across the voltage divider; and current generating means responsive to the detected replica of the modulating signal for establishing a current in the PIN diode for linearly varying its resistance in inverse relation to the instantaneous level of the modulating signal so as to develop a carrier signal across the PIN diode which is substantially free of both amplitude and angle modulation.

Claim 8

An amplitude limiter for removing the modulation from a carrier signal amplitude modulated by a modulating signal comprising: detecting means responsive to the carrier signal for providing a replica of the modulating signal; a voltage divider comprising a series connected fixed resistance and PIN diode having a substantially linear resistance versus current characteristic above a given frequency, the fixed resistance and PIN diode having a common node therebetween; means for applying the amplitude modulated carrier signal across the voltage divider; and current generating means responsive to the detected replica of the modulating signal for establishing a current in the PIN diode for linearly varying its resistance in inverse relation to the instantaneous level of the modulating signal so as to develop a carrier signal at the common node which is substantially free of both amplitude and angle modulation.

Claim 9

An amplitude limiter for removing the modulation from a carrier signal amplitude modulated by a modulating signal comprising: detecting means responsive to the carrier signal for providing a replica of the modulating signal; a voltage divider comprising a series connected fixed resistance and PIN diode having a substantially linear resistance versus current characteristic above a given frequency, the fixed resistance and PIN diode having a common node therebetween; means for applying the amplitude modulated carrier signal across the voltage divider; and current generating means responsive to the detected replica of the modulating signal for establishing a current in the PIN diode for linearly varying its resistance in inverse relation to the instantaneous level of the modulating signal so as to develop a carrier signal at the common node which is substantially free of both amplitude and angle modulation.