Dispersive target detection

Abstract

A first multitude of frequency elements between a first lower frequency and a first upper frequency; and a second multitude of frequency elements between a second lower frequency and a second upper frequency are transmitted. The second lower frequency and the second upper are shifted from the first upper frequency by the first delta, respectively, by a delta frequency. A return signal is split into: a first return signal comprising a first in-phase component and a first quadrature phase component; and a second return signal comprising a second in-phase component and a second quadrature phase component. A combined return signal is generated by combining the first return signal and the second return signal phase shifted by the first delta frequency. A probability of a potential target is determined when the combined return signal exceeds a threshold.

What is claimed is: 
     
         1 . A process comprising:
 a) transmitting a combined frequency agile signal waveform comprising a combination of:
 i) a first frequency agile signal waveform comprising a first multitude of frequency elements between: a first lower frequency and a first upper frequency; and 
 ii) a second frequency agile signal waveform comprising a second multitude of frequency elements between a second lower frequency and a second upper frequency, wherein:
 (1) the second lower frequency is shifted from the first lower frequency by a first delta frequency; and 
 (2) the second upper frequency is shifted from the first upper frequency by the first delta frequency; 
 
   b) receiving a combined return signal;   c) splitting the combined return signal into at least the following:
 i) a first return signal comprising a first in-phase component and a first quadrature phase component; 
 ii) a second return signal comprising a second in-phase component and a second quadrature phase component; 
   d) generating a second phase shifted return signal by phase shifting the second return signal by the first delta frequency;   e) generating a combined return signal comprises combining the first return signal and the second phase shifted return signal; and   f) determining a probability of a potential target when the combined return signal exceeds a threshold.   
     
     
         2 . The process according to claim Error! Reference source not found, wherein at least one of the first frequency agile signal waveform and second frequency agile signal waveform comprises a step chirp signal waveform. 
     
     
         3 . The process according to claim Error! Reference source not found, wherein at least one of the first frequency agile signal waveform and second frequency agile signal waveform comprises a linear frequency modulated waveform. 
     
     
         4 . The process according to claim Error! Reference source not found, wherein at least one of the first frequency agile signal waveform and second frequency agile signal waveform are phase aligned. 
     
     
         5 . The process according to claim Error! Reference source not found, wherein the first delta frequency correlates to a cutoff frequency of a target of interest. 
     
     
         6 . The process according to claim Error! Reference source not found, wherein the first frequency agile signal waveform comprises a first bandwidth. 
     
     
         7 . The process according to  claim 6 , wherein the second frequency agile signal waveform comprises a second bandwidth equal to the first bandwidth. 
     
     
         8 . The process according to  claim 1 , wherein the combined frequency agile signal waveform further comprises a third frequency agile signal waveform, the third frequency agile signal waveform comprising a third multitude of frequency elements between a third lower frequency and a third upper frequency. 
     
     
         9 . The process according to  claim 8 , wherein:
 a) the third lower frequency is shifted from the first lower frequency by a second delta frequency that is different than the first delta frequency; and   b) the third upper frequency is shifted from the first upper frequency by the second delta frequency.   
     
     
         10 . The process according to  claim 9 , further comprising splitting the return signal into a third return signal comprising a third in-phase component and a third quadrature phase component. 
     
     
         11 . The process according to  claim 10 , further comprising generating a third phase shifted return signal by phase shifting the third return signal by the second delta frequency. 
     
     
         12 . The process according to  claim 11 , further comprising combining the third phase shifted return signal into the combined return signal. 
     
     
         13 . The process according to  claim 1 , wherein:
 a) the combined frequency agile signal waveform further comprises a third frequency agile signal waveform comprising:
 i) a third bandwidth; and 
 ii) a third multitude of frequency elements between:
 (1) a third lower frequency; and 
 (2) a third upper frequency, the third lower frequency and third upper frequency shifted from the first lower frequency and first upper frequency respectively by a second delta frequency that is different than the first delta frequency; 
 
   b) the splitting the return signal further comprises splitting the return signal into a third return signal comprising:
 i) a third in-phase component; and 
 ii) a third quadrature phase component; and 
   c) generating a third phase shifted return signal by phase shifting the third return signal by the second delta frequency; and   d) the generating a combined return signal further comprises combining the third phase shifted return signal into the combined return signal.   
     
     
         14 . The process according to  claim 1 , wherein the combined frequency agile signal waveform further comprises at least one additional frequency agile signal waveform. 
     
     
         15 . The process according to  claim 14 , further comprising splitting the return signal into at least one additional return signal, wherein each of the at least one additional return signal comprises an additional in-phase component and an additional quadrature phase component. 
     
     
         16 . The process according to  claim 15 , further comprising generating an additional phase shifted return signal for each of the at least one additional return signal by phase shifting the additional return signal by an additional delta frequency. 
     
     
         17 . The process according to  claim 15 , further comprising combining each additional phase shifted return signal into the combined return signal. 
     
     
         18 . The process according to  claim 15 , wherein each of the at least one additional frequency agile signal waveform comprises an additional multitude of frequency elements between an additional third lower frequency and an additional upper frequency. 
     
     
         19 . The process according to  claim 18 , wherein:
 a) each additional lower frequency is shifted from the first lower frequency by an additional delta frequency; and   b) each additional upper frequency is shifted from the first upper frequency by the additional delta frequency.   
     
     
         20 . The process according to  claim 19 , wherein the additional delta frequency is different than the first delta frequency.