Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
193 words
A DME receiver, responsive to an RF input signal for generating a linear baseband replica of said RF input for distance determining purposes, including: a first mixer, coupled to said RF input signal, and to a local oscillator signal, an IF amplifier and bandpass filter, serially connected to said first mixer, a second mixer with two inputs and an output, and, signal processing means with two outputs coupled between said bandpass filter and said second mixer for processing a signal from said bandpass filter to generate a first output signal and a second output signal comprising a hard limited version of said RF input signal, said signal processing means including phase shift means for phase adjusting said second output signal relative to said first output signal, said phase shift means comprising an active circuit element with an input and two outputs, variable reactive circuit means coupled between said two outputs, said two outputs of said active circuit element providing said first and second output signals, respectively, whereby with the relative phases of said first and second output signals adjusted, said second mixer produces, at baseband, a linear replica of said RF input signal.
Claim 2
Dependent Claim
193 words
A DME receiver, responsive to an RF input signal for generating a linear baseband replica of said RF input for distance determining purposes, including: a first mixer, coupled to said RF input signal, and to a local oscillator signal, an IF amplifier and bandpass filter, serially connected to said first mixer, a second mixer with two inputs and an output, and, signal processing means with two outputs coupled between said bandpass filter and said second mixer for processing a signal from said bandpass filter to generate a first output signal and a second output signal comprising a hard limited version of said RF input signal, said signal processing means including phase shift means for phase adjusting said second output signal relative to said first output signal, said phase shift means comprising an active circuit element with an input and two outputs, variable reactive circuit means coupled between said two outputs, said two outputs of said active circuit element providing said first and second output signals, respectively, whereby with the relative phases of said first and second output signals adjusted, said second mixer produces, at baseband, a linear replica of said RF input signal.
Claim 3
Dependent Claim
74 words
The apparatus of claim 1 in which said signal processing means includes a third mixer coupled between said bandpass filter and said second mixer, a first input of said third mixer comprising a replica of an output of said bandpass filter and a second input of said third mixer comprising a signal in fixed frequency relation to said local oscillator signal, whereby second mixer has input signals of frequency lower than said intermediate frequency.
Claim 4
Dependent Claim
16 words
The apparatus of claim 1 in which said variable reactive circuit means comprises a variable capacitor.
Claim 5
Dependent Claim
57 words
The apparatus of claim 1 in which said signal processing means comprises a power splitter with input coupled to said bandpass filter and a first output coupled to said second mixer, and a hard limiter and phase adjusting means serially connected between a second output of said power splitter and a second input of said second mixer.
Claim 6
Dependent Claim
135 words
The apparatus of claim 1 in which said signal processing means comprises a power splitter with an input coupled to said bandpass filter, amplifying means responsive to one output of said power splitter for supplying an AGC signal, a third mixer with an output and responsive to another output of said power splitter and to another local oscillator signal, fixed in frequency relative to said local oscillator signal, delay means and a video amplifier serially connected to said output of said third mixer, said video amplifier having an AGC input connected to said AGC signal, signal splitter means with an input and two outputs and including said phase shift means connected between said video amplifier and said second mixer, and a hard limiter coupling another output of said signal splitter means and said second mixer.