Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
179 words
A method (50) of enhancing the radar cross section of a target (12) when using an impulse radar system (10), said method (50) comprising the steps of: transmitting (51) a pilot impulse radar pulse at a target, which pilot pulse comprises a plurality of individual pulses having respective distinct frequencies generated by an impulse radar system; receiving (52) a return impulse radar pulse from the target, which return pulse provides information indicative of scattering centers on the target, and wherein the return pulse is used as a calibration signal; processing (53) the calibration signal corresponding to the return impulse radar pulse to form a phase conjugate impulse radar pulse; and transmitting (54) the phase conjugate impulse radar pulse at the target; processing (55) a target return signal derived from the transmitted phase conjugate impulse radar pulse; and wherein the target return signal derived from the transmitted phase conjugate impulse radar pulse has an enhanced radar cross section of the target since the waveform of the transmitted phase conjugate impulse radar pulse is matched to the characteristics of the target.
Claim 2
Independent Claim
148 words
A method of enhancing the radar cross section of a target when using an impulse radar system said method comprising the steps of: transmitting a train of impulse radar pulses at a target, which pulses comprise a plurality of [individual pulses having respective] distinct frequencies generated respectively by multiple frequency sources of an impulse radar system; receiving return pulses from the target, which return pulses comprise information indicative of scattering centers on the target; adaptively adjusting the phases of the transmitted pulses in response to the return pulses in such a manner as to cause the radar cross section contributed by the backward traveling wave on the target to be made to add in phase in the received direction; processing said return pulses by summing the spectral components comprising return pulses derived from the transmitted pulses having adjusted phases to increase the radar cross section of the target.
Claim 3
Dependent Claim
42 words
The method (50) of Claim 2 wherein the step of transmitting impulse radar pulses comprises transmitting impulse radar pulses wherein the pulse repetition time between pulses is made equal to the time delay between scatter returns from scattering centers on the target.
Claim 4
Dependent Claim
51 words
The method (50) of Claim 2 wherein the step of adaptively adjusting the phases of the transmitted pulses comprises changing a starting frequency of Fourier spectral lines of the waveform of the impulse signal to provide for desired phase differences between impulses to generate the transmitted phase conjugate impulse radar pulse.
Claim 5
Dependent Claim
40 words
The method of claim 1 wherein the step of transmitting the phase conjugated pulse comprises transmitting a phase conjugate impulse radar pulse generated by selecting and transmitting differing predetermined subsets of frequencies from a relatively large number of predetermined frequencies.
Claim 6
Dependent Claim
181 words
An impulse radar system (10) comprising: a transmitter (21) for transmitting a pilot impulse radar pulse at a target (12), which pilot pulse comprises a plurality of individual pulses having respective distinct frequencies; a receiver (22) for receiving a return impulse radar pulse from the target (12), which return pulse provides information indicative of scattering centers on the target, which return pulse provides a calibration signal; and processing means (23, 35) coupled to the transmitter (21) and receiver (22) for processing the calibration signal corresponding to the return impulse radar pulse to form a phase conjugate impulse radar pulse; wherein the transmitter (21) is adapted to transmit the phase conjugate impulse radar pulse at the target (12), and wherein the receiver is adapted to process a target return signal derived from the transmitted phase conjugate impulse radar pulse, and wherein the target return signal derived from the transmitted phase conjugate impulse radar pulse enhances the radar cross section of the target since the waveform of the transmitted phase conjugate impulse radar pulse is matched to the characteristics of the target (12).
Claim 7
Dependent Claim
173 words
An impulse radar system comprising: a transmitter for transmitting impulse radar pulses at a target, wherein said transmitter comprises a plurality of individual frequency sources for generating a train of pulses which pulses comprise a plurality of [individual pulses having respective] distinct frequencies; a receiver for receiving return pulses from the target, which return pulses provide information indicative of scattering centers on the target; and processing means coupled to the transmitter and receiver for processing the return pulses and for adaptively adjusting the phases of the transmitted pulses that are transmitted at the target in response to the return pulses in such a manner as to cause the radar cross section contributed by the backward traveling wave on the target to be made to add in phase in the received direction; and wherein the transmitter transmits the pulses having adaptively adjusted phases at the target, and wherein the receiver sums the spectral components comprising return pulses derived from the transmitted pulses having adjusted phases to increase the radar cross section of the target.
Claim 8
Dependent Claim
43 words
The system of Claim 7 wherein the transmitter includes means for varving the repetition rate of the impulse radar pulses wherein the pulse repetition time between pulses is made equal to the time delay between scatter returns from scattering centers on the target.
Claim 9
Dependent Claim
43 words
The system of Claim 7 wherein the transmitter further comprises means for changing a starting frequency of Fourier spectral lines of the waveform of the impulse signal to provide for desired phase differences between respective impulses to generate the transmitted phase conjugated pulse.
Claim 10
Dependent Claim
49 words
The system of Claim 7 wherein the transmitter includes means for selecting and transmitting differing predetermined subsets of frequencies from a predetermined number of available frequencies. wherein the pulse repetition time between pulses is made equal to the time delay between scatter returns from scattering centers on the target.
Claim 11
Dependent Claim
36 words
The system of Claim 7 wherein the transmitter comprises means for adjusting the phases of each spectral component such that the radar cross section for selected frequencies have equal phase at a desired angle of incidence.