Signal limiting apparatus having improved spurious signal performance and methods

A limiter apparatus for amplitude limiting an input information signal having a plurality of frequency components, comprising:

• means for filtering said input signal, said means having a low pass frequency response for providing at a first output selected low frequency components in said input signal and having a high pass frequency response for providing at a second output selected higher frequency components present in said input signal;
• controllable attenuating means coupled to said second output for selectively attenuating said high frequency components according to the value of a control signal applied thereto;
• combining means responsive to an output of said attenuating means and said first output of said filtering means for providing at an output a combined signal;
• and
• limiting means responsive to said combined signal to limit the magnitude of said combined signal according to a first threshold value and for providing said control signal for said attenuating means for controlling said attenuation of said high frequency components according to the extent of limiting whereby said limiter apparatus operates to provide reduced spurious frequencies for those higher frequencies contained within said input signal as compared to said lower frequency components.