Methods and systems for detecting repetitive synchronized signal events

• US 8,433,739 B2
• Filed: 06/27/2007
• Issued: 04/30/2013
• Est. Priority Date: 06/27/2007
• Status: Expired due to Fees

• Current Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Integrated Systems LP (L3Harris Technologies, Inc.)
• Inventors: Ha, Stephen T.
• Primary Examiner(s): Do, Chat
• Assistant Examiner(s): Hughes, Kevin G
• Application Number:
  US11/823,472
• Publication Number:
  US 20090003422A1
• Time in Patent Office: 2,134 Days
• Field of Search: 708/400
• US Class Current: 708/400
• CPC Class Codes: H04B 14/006 Angle modulation

Abstract

Repetitive synchronized signal events may be detected in received raw signal data that contains a signal. The type of signal, element length (or minimum interval) and/or other characteristics of such repetitive synchronized signal events may also be optionally determined. The disclosed methods and systems may be implemented for processing signals in real time as part of a receiver or transceiver system, or may be implemented by one or more computer processing components that are configured to process stored raw signal data or signal data received from another source, such as across a computer network.

Claims

1. A method of processing signal data, comprising:

providing one or more processors;

receiving a time series of said signal data; and

using one or more of the processors to process the signal data;

where the one or more processors are programmed to process the signal data by performing the following steps;

obtaining reinforceable repetitive synchronous data from said time series of signal data,

obtaining time-time data from said reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces,

adding said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data, and

outputting said sum of said time-time data for at least one of display, storage, or further processing; and

wherein said reinforceable repetitive synchronous data comprises rectified average delta data.

2. The method of claim 1, where the one or more processors are programmed to process the signal data by performing the following steps:

identifying a high amplitude event in said sum of said time-time data, and determining the presence of a repetitive synchronous event in said signal data from said high amplitude event.

3. The method of claim 1, where the one or more processors are programmed to process the signal data by performing the following steps:

identifying a synchronous pattern within said sum of said time-time data, and determining one or more characteristics of said signal data.

4. The method of claim 1, where the one or more processors are programmed to process the signal data by performing the following steps:

providing an initial estimate of element length of a repetitive synchronous event in said signal data, then orienting said multiple data traces of said time-time data relative to each other based on said estimated element length prior to adding said time-time data in phase across said multiple data traces in a straight line and such that the wrap around length of each data trace is equal to the element length or a multiple of the element length, and then determining a revised estimate of said element length based on said sum of said time-time data.

5. The method of claim 4, where the one or more processors are programmed to process the signal data by performing the following steps:

obtaining an amplitude spectrum of said reinforceable repetitive synchronous data, and then providing said initial estimate of element length of said repetitive synchronous event from said amplitude spectrum of said reinforceable repetitive synchronous data.

6. The method of claim 5, where the one or more processors are programmed to process the signal data by performing the following steps:

applying a Fast Fourier Transform to said reinforceable repetitive synchronous data to obtain said amplitude spectrum, and adding said time-time data in phase across said multiple data traces in a straight line to obtain a Radon sum of said time-time data.

7. The method of claim 4, where the one or more processors are programmed to process the signal data by performing the steps of adding said time-time data in phase across said multiple data traces in a straight line to obtain a Radon sum of said time-time data that includes one or more peaks;

and determining a revised estimate of said element length to be equal to either of;

the wrap around length of the time-time data in the case where the Radon sum of said time-time data includes a single peak;

or

the distance between the two closest peaks in the case where the Radon sum of said time-time data includes multiple peaks.

8. The method of claim 4, where the one or more processors are programmed to process the signal data by performing the steps of adding said time-time data in phase across said multiple data traces in a straight line to obtain Radon sums of said time-time data corresponding to multiple wrap around length estimates;

and then determining a revised estimate of said element length to be equal to the wrap around length of the time-time data corresponding to the Radon sum having a peak with the largest Radon sum value.

9. The method of claim 1,

where the one or more processors are programmed to process the signal data by performing the following steps:

obtaining I-Q data from said time series of said signal data,

obtaining reinforceable repetitive synchronous data from said I-Q data of said time series of said signal data,

obtaining time-time data from said reinforceable repetitive synchronous data corresponding to said time series of said signal data, said time-time data comprising multiple data traces with each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces, and

adding said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data corresponding to said time series of said signal data.

10. The method of claim 1, said method comprising:

receiving multiple time series of said signal data; and

where the one or more processors are programmed to process the signal data performing the following steps;

obtaining I-Q data from said multiple time series of said signal data,

obtaining reinforceable repetitive synchronous data from said I-Q data of each of said multiple time series of said signal data,

adding said reinforceable repetitive synchronous data corresponding to said multiple time series of said signal data to obtain a sum of reinforceable

repetitive synchronous data,

obtaining time-time data from said sum of reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of a time series than each other of said multiple data traces, and

adding said time-time data in phase from said sum of reinforceable repetitive synchronous data across said multiple data traces in a straight line to obtain a sum of said time-time data corresponding to said multiple time series of said signal data.

11. The method of claim 1, further comprising:

providing a non-transitory memory storing a computer program of instructions; and

where the one or more processors are programmed to process the signal data by performing the following steps;

obtaining reinforceable repetitive synchronous data from said signal data,

obtaining time-time data from said reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces,

adding said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data, and

outputting said sum of said time-time data for at least one of display, storage, or further processing.

12. A non-transitory tangible computer readable medium including a computer program of instructions, the computer program of instructions comprising code that is executable one or more processors to detect repetitive synchronized signal events from a received time series of signal data by performing the following steps:

obtaining reinforceable repetitive synchronous data from said time series of data;

obtaining time-time data comprising multiple data traces, each of said data traces corresponding to a different time segment of the time series than each other of said multiple data traces;

adding said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time time data; and

outputting the sum of said time-time data for at least one of display, storage, or further processing;

wherein reinforceable repetitive synchronous data comprises rectified average delta data.

13. The computer readable medium of claim 12, wherein said signal data comprises raw signal data that includes at least one signal, said repetitive synchronized signal event corresponding to said at least one signal.

14. The computer readable medium of claim 13, wherein said signal comprises a phase-shift key (PSK) signal and said repetitive synchronized signal event comprises a phase transition in said PSK signal;

or wherein said signal comprises a frequency modulated continuous wave (FMCW) signal and said repetitive synchronized signal event comprises a frequency slope change in said FMCW signal;

or wherein said signal comprises a frequency-shift key (FSK) signal and said repetitive synchronized signal event comprises a frequency transition in said FSK signal.

15. The computer readable medium of claim 13, wherein said repetitive synchronized signal event comprises an envelope in the said signal encoding a fixed periodic data pattern.

16. The computer readable medium of claim 13, wherein said signal comprises a radar signal.

17. The computer readable medium of claim 13, where the computer program of instructions further comprises code that is executable by one or more processors to determine the signal type of said signal based on said in-phase sum of reinforceable repetitive synchronous data obtained from said signal data.

18. The computer readable medium of claim 17, where the computer program of instructions further comprises code that is executable by one or more processors to obtain I-Q data from said signal data, and obtain unwrapped phase of said I-Q data;

wherein said signal comprises a PSK signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from delta phase data obtained from the unwrapped phase of I-Q data of said signal data;

or wherein said signal comprises a FSK signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from a differentiation of delta phase data obtained from the unwrapped phase of I-Q data of said signal data;

or wherein said signal comprises a FMCW signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from a double differentiation of delta phase data obtained from the unwrapped phase of I-Q data of said signal data.

19. The computer readable medium of claim 17, where the computer program of instructions further comprises code that is executable by one or more processors to obtain I-Q data from said signal data, differentiate the I-Q data, and obtain an envelope from the differentiated I and Q data;

wherein said signal comprises a FSK signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from a level change detection of the envelope obtained from the differentiated I and Q data of said signal data;

or wherein said signal comprises a FMCW signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from a frequency peak detection of the envelope obtained from the differentiated I and Q data of said signal data.

20. The computer readable medium of claim 17, where the computer program of instructions further comprises code that is executable by one or more processors to perform at least one of the following three sets of steps:

obtain I-Q data from said signal data, obtain unwrapped phase of said I-Q data, and obtain an envelope from the I and Q data encoding a fixed periodic data pattern;

wherein said signal comprises a PSK signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from the envelope of the unwrapped phase of I and Q data of said signal data encoding a fixed periodic data pattern;

obtain I-Q data from said signal data, differentiate the I-Q data, and obtain an envelope from the I and Q data encoding a fixed periodic data pattern;

wherein said signal comprises a FSK signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from the envelope obtained from the differentiated I and Q data of said signal data encoding a fixed periodic data pattern; and

obtain I-Q data from said signal data, differentiate the I-Q data, and obtain an envelope from the I and Q data encoding a fixed periodic data pattern;

wherein said signal comprises a FMCW signal and wherein said in-phase sum of reinforceable repetitive synchronous data is obtained from the envelope obtained from the differentiated I and Q data of said signal data encoding a fixed periodic data pattern.

21. The computer readable medium of claim 12, where the computer program of instructions further comprises code that is executable by one or more processors to determine a minimum element length of said repetitive synchronous event based on said in-phase sum of reinforceable repetitive synchronous data obtained from said signal data.

22. The computer readable medium of claim 12, where the computer program of instructions further comprises code that is executable by one or more processors to receive said signal data;

and perform said step of detecting the presence of said repetitive synchronized signal event in real time as said signal data is received.

23. A system for processing signal data, comprising one or more processors, one or more of the processors programmed to:

receive a time series of said signal data;

obtain I-Q data from said time series of signal data;

obtain reinforceable repetitive synchronous data from said I-Q data;

obtain time-time data from said reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces;

add said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data corresponding to said time series of said signal data; and

output the sum of said time-time data for at least one of display, storage, or further processing;

wherein said reinforceable repetitive synchronous data comprises rectified average delta data.

24. The system of claim 23, wherein one or more of the processors are further programmed to identify a high amplitude event in said sum of said time-time data, and to determine the presence of a repetitive synchronous event in said signal data from said high amplitude event.

25. The system of claim 23, wherein one or more of the processors are further programmed to identify a synchronous pattern in said sum of said time-time data, and to determine one or more characteristics of said signal data.

26. The system of claim 23, wherein one or more of the processors are further programmed to:

provide an initial estimate of element length of a repetitive synchronous event in said signal data;

then orient said multiple data traces of said time-time data relative to each other based on said estimated element length prior to adding said time-time data in phase across said multiple data traces, and such that a wrap around length of each data trace is equal to the element length or a multiple of the element length; and

then determine a revised estimate of said element length based on said sum of said time-time data.

27. The system of claim 26, wherein one or more of the processors are further programmed to obtain an amplitude spectrum of said reinforceable repetitive synchronous data;

and then to provide said initial estimate of element length of said repetitive synchronous event from said amplitude spectrum of said reinforceable repetitive synchronous data.

28. The system of claim 27, wherein one or more of the processors are further programmed to apply a Fast Fourier Transform to said reinforceable repetitive synchronous data to obtain said amplitude spectrum;

and to add in phase data across said multiple data traces in a straight line to obtain a Radon sum of said time-time data.

29. The system of claim 26, wherein one or more of the processors are further programmed to:

add said time-time data in phase across said multiple data traces in a straight line to obtain a Radon sum of said time-time data that includes one or more peaks; and

determine a revised estimate of said element length to be equal to either of;

the wrap around length of the time-time data in the case where the Radon sum of said time-time data includes a single peak, or

the distance between the two closest peaks in the case where the Radon sum of said time-time data includes multiple peaks.

30. The system of claim 26, wherein one or more of the processors are further programmed to add said time-time data in phase across said multiple data traces in a straight line to obtain Radon sums of said time-time data corresponding to multiple wrap around length estimates;

and then determine a revised estimate of said element length to be equal to the wrap around length of the time-time data corresponding to the Radon sum having a peak with the largest Radon sum value.

31. The system of claim 23, wherein one or more of the processors are further programmed to:

receive multiple time series of said signal data;

obtain I-Q data from each of said multiple time series of said signal data;

obtain reinforceable repetitive synchronous data from said I-Q data of each of said multiple time series of said signal data;

add said reinforceable repetitive synchronous data corresponding to said multiple time series of said signal data to obtain a sum of reinforceable repetitive synchronous data;

obtain time-time data from said sum of reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of a time series than each other of said multiple data traces; and

add said time-time data from said sum of reinforceable repetitive synchronous data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data corresponding to said multiple time series of said signal data.

35. The system of claim 23, further comprising:

a non-transitory memory storing a computer program of instructions; and

wherein the one or more of the processors are configured to execute the computer program of instructions to;

receive said time series of signal data,

obtain I-Q data from said signal data,

obtain reinforceable repetitive synchronous data from said I-Q data,

obtain time-time data from said reinforceable repetitive synchronous data, said time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces, and

add said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time-time data.

32. A system for detecting repetitive synchronized signal events, said system comprising one or more processors, the one or more processors being programmed to operate as an event detector, said event detector being configured to receive a time series of signal data and detect repetitive signal events from said received time series of signal data by:

obtaining reinforceable repetitive synchronous data from said time series of data;

obtaining time-time data comprising multiple data traces, each of said data traces corresponding to a different time segment of the time series than each other of said multiple data traces;

adding said time-time data in phase across said multiple data traces in a straight line to obtain a sum of said time time data; and

outputting the sum of said time-time data for at least one of display, storage, or further processing;

wherein reinforceable repetitive synchronous data comprises rectified average delta data.

33. The system of claim 32, wherein said signal data comprises raw signal data that includes at least one signal;

wherein said repetitive synchronized signal event corresponds to said at least one signal; and

wherein said system further comprises receive path circuitry coupled to receive said raw signal data from at least one antenna, said receive path circuitry being coupled between said antenna and said one or more processors programmed to implement the event detector.

34. The system of claim 33, wherein said signal comprises a phase-shift key (PSK) signal and said repetitive synchronized signal event comprises a phase transition in said PSK signal;

or wherein said signal comprises a frequency modulated continuous wave (FMCW) signal and said repetitive synchronized signal event comprises a frequency slope change in said FMCW signal;

or wherein said signal comprises a frequency-shift key (FSK) signal and said repetitive synchronized signal event comprises a frequency transition in said FSK signal.

36. The system of claim 33, wherein said repetitive synchronized signal event comprises an envelope in the said signal encoding a fixed periodic data pattern.

37. The system of claim 33, wherein said signal comprises a radar signal.

38. The system of claim 33, wherein said event detector is further configured to determine the signal type of said signal based on said in-phase sum of reinforceable repetitive synchronous data obtained from said signal data.

39. The system of claim 38, wherein said signal comprises a PSK signal and wherein said event detector is configured to obtain I-Q data from said signal data, obtain unwrapped phase of said I-Q data, and obtain an in-phase sum of reinforceable repetitive synchronous data from delta phase data obtained from the unwrapped phase of I-Q data of said signal data;

or

wherein said signal comprises a FSK signal and wherein event detector is configured to obtain I-Q data from said signal data, obtain unwrapped phase of said I-Q data, and obtain said in-phase sum of reinforceable repetitive synchronous data from a differentiation of delta phase data obtained from the unwrapped phase of I-Q data of said signal data;

or

wherein said signal comprises a FMCW signal and wherein said event detector is configured to obtain I-Q data from said signal data, obtain unwrapped phase of said I-Q data, and obtain an in-phase sum of reinforceable repetitive synchronous data from a double differentiation of delta phase data obtained from the unwrapped phase of I-Q data of said signal data.

40. The system of claim 38, wherein said signal comprises a FSK signal and wherein said event detector is configured to obtain I-Q data from said signal data, differentiate the I-Q data, obtain an envelope from the differentiated I and Q data, and obtain an in-phase sum of reinforceable repetitive synchronous data from a level change detection of the envelope obtained from the differentiated I and Q data of said signal data;

or

wherein said signal comprises a FMCW signal and wherein said event detector is configured to obtain I-Q data from said signal data, differentiate the I-Q data, obtain an envelope from the differentiated I and Q data, and obtain an in-phase sum of reinforceable repetitive synchronous data from a frequency peak detection of the envelope obtained from the differentiated I and Q data of said signal data.

41. The system of claim 38, wherein said signal comprises a PSK signal and wherein said event detector is configured to to obtain I-Q data from said signal data, obtain an envelope from the I and Q data encoding a fixed periodic data pattern, and obtain an in-phase sum of reinforceable repetitive synchronous data from the envelope of the unwrapped phase of I and Q data of said signal data encoding a fixed periodic data pattern;

or wherein said signal comprises a FSK signal and wherein said event detector is configured to to obtain I-Q data from said signal data, different the I-Q data, obtain an envelope from the differentiated I and Q data encoding a fixed periodic data pattern, and obtain an in-phase sum of reinforceable repetitive synchronous data from the envelope obtained from the differentiated I and Q data of said signal data encoding a fixed periodic data pattern;

or wherein said signal comprises a FMCW signal and wherein said event detector is configured to to obtain I-Q data from said signal data, different the I-Q data, obtain an envelope from the differentiated I and Q data encoding a fixed periodic data pattern, and obtain an in-phase sum of reinforceable repetitive synchronous data from the envelope obtained from the differentiated I and Q data of said signal data encoding a fixed periodic data pattern.

42. The system of claim 32, wherein said event detector is further configured to determine a minimum element length of said repetitive synchronous event based on said in-phase sum of reinforceable repetitive synchronous data obtained from said signal data.

43. The system of claim 32, wherein said event detector is further configured to receive said signal data and to detect the presence of said repetitive synchronized signal event in real time as said signal data is received.

44. The system of claim 32, further comprising a non-transitory memory storing a computer program of instructions;

and where one or more of the processors is configured to execute the computer program of instructions to implement the event detector.

45. A system for detecting repetitive synchronized signal events, said system comprising:

an antenna configure to receive radio frequency (RF) signal data;

receive path circuitry coupled to receive the RF signal data from the antenna and to provide the received RF signal data as digitized signal data;

event detector circuitry coupled to receive the digitized signal data from the receive path circuitry, the event detector circuitry comprising one or more processors programmed to;

obtain reinforceable repetitive synchronous data from a time series of the signal data,

obtain time-time data from the reinforceable repetitive synchronous data, the time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces,

add the time-time data in phase across the multiple data traces in a straight line to obtain a sum of the time-time data,

detect the presence of a repetitive synchronized signal even in said signal data from said sum of time-time data, and

output the sum of the time-time data as a signal for at least one of display, storage, or further processing,

wherein said reinforceable repetitive synchronous data comprises rectified average delta data.

46. The system of claim 45, further comprising at least one of a display, storage or processor circuitry coupled to the event detector circuitry;

and where the one or more processors of the event detector circuitry are further programmed to;

output the sum of the time-time data as a signal to at least one of the display, storage or processor circuitry for at least one of display, storage, or further processing.

47. A method for detecting repetitive synchronized signal events, said method comprising detecting the presence of said repetitive synchronized signal events by:

providing an antenna configure to receive radio frequency (RF) signal data;

providing receive path circuitry coupled to receive the RF signal data from the antenna and to provide the received RF signal data as digitized signal data;

providing event detector circuitry coupled to receive the digitized signal data from the receive path circuitry, the event detector circuitry comprising one or more processors; and

using the one or more of the processors of the event detector circuitry to perform the following steps;

obtain reinforceable repetitive synchronous data from a time series of the signal data,

obtain time-time data from the reinforceable repetitive synchronous data, the time-time data comprising multiple data traces, each of said multiple data traces corresponding to a different time segment of the time series than each other of said multiple data traces,

add the time-time data in phase across the multiple data traces in a straight line to obtain a sum of the time-time data,

detect the presence of a repetitive synchronized signal event in said signal data from sum of time-time data, and

output the sum of the time-time data as a signal to at least one of a display, storage, or further processing,

wherein said reinforceable repetitive synchronous data comprises rectified average delta data.

48. The method of claim 47, further comprising:

providing at least one of a display, storage or processor circuitry coupled to the event detector circuitry; and

using the one or more of the processors of the event detector circuitry to perform the following step;

output the sum of the time-time data as a signal to at least one of the display, storage or processor circuitry for at least one of display, storage, or further processing.