I-Q channel adaptive line enhancer

An adaptive line enhancer comprising

• input means for supplying an analog input sample signal,
• oscillator signal means for supplying a local oscillator signal,
• local oscillator delay means for providing a 90.degree. delayed local oscillator signal,
• I channel signal means comprising a first signal mixer means for mixing said analog input sample signal and said local oscillator signal and for supplying an I channel analog signal,
• first analog-to-digital converter means coupled to receive said I channel analog signal and for providing a first digitized signal representative thereof,
• first adaptive filter means coupled to receive said first digitized signal for providing a first adaptive filter output signal,
• first digital-to-analog converter means coupled to receive said first adaptive filter output signal,
• narrowband I channel means comprising second mixer means which receives said first adaptive filter output signal and said local oscillator signal for providing a first narrowband output signal,
• Q channel signal means comprising third mixer means for mixing said analog input signal and said 90.degree. delayed local oscillator signal and for supplying a Q channel analog signal,
• second analog-to-digital converter means coupled to receive said Q channel analog signal and for providing a second digitized signal representative thereof,
• second adaptive filter means coupled to receive said second digitized signal for providing a second adaptive filter output signal,
• second digital-to-analog converter means coupled to receive said second adaptive filter output signal,
• narrowband Q channel means comprising fourth mixer means which receives said second adaptive filter output signal and said 90.degree. delayed local oscillator signal for providing a second narrowband output signal,
• signal means coupled to receive said first and second narrowband output signals which is constructed to sum said first and second narrowband output signals, to provide a mixed narrowband output signal and to subtract said mixed narrowband output signal from said analog input sample signal in order to supply a wideband channel output signal, and
• error means for sampling said wideband output signal to provide a wideband sample signal and for down converting said wideband sample signal to provide an adaptive control weight signal to both of said first and second adaptive filter means.