Signal type identification

• US 6,904,269 B1
• Filed: 06/02/2000
• Issued: 06/07/2005
• Est. Priority Date: 06/02/2000
• Status: Active Grant

• Current Assignee: Tektronix Incorporated (Fortive Corp.)
• Original Assignee: Tektronix Incorporated (Fortive Corp.)
• Inventors: Hill, Thomas C., Jenkins, R. Eben, Deshpande, Nikhil, Engholm, Kathryn A.
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): Orgad, Edan
• Application Number:
  US09/587,491
• Time in Patent Office: 1,831 Days
• Field of Search: 455/142, 455/143, 455/110, 455/67.1, 455/67.2, 455/67.3, 455/150.1, 455/159.1, 455/226.1, 455/226.4, 455/296, 455/410, 455/411, 455/140, 455/423, 455/424, 455/425, 375/227, 375/228, 375/224, 375/316, 324/76.11, 324/76.19, 324/76.22, 762/76, 762/77
• US Class Current: 455/142
• CPC Class Codes: H04L 27/0012 arrangements for identifying the type of modulation

Abstract

A method of identifying a signal type uses parameters of the signal as a basis for automatic identification. A signal of interest is selected from a display of a spectral waveform for a specified frequency. An occupied bandwidth for the signal of interest is estimated and, if the occupied bandwidth is common to more than one known signal type, a complementary cumulative distribution function of peak power for the signal of interest is estimated. The signal type may be identified as a function of these parameters. Additionally the frequency of the signal of interest may be compared with a database of spectral assignments for known signal types to provide further information about the signal of interest.

Claims

1. A method of identifying a signal type for an unknown signal comprising the steps of:

selecting the unknown signal from a displayed spectral waveform for a specified range of frequencies;

processing spectral data representing the unknown signal to ascertain characteristics of the unknown signal without demodulating the unknown signal; and

from the characteristics of the unknown signal determining an identification of the signal type.

2. The method as recited in claim 1 wherein the determining step comprises the step of comparing the frequency of the unknown signal with a database of spectral assignments for a plurality of known signal types to identify the signal type.

3. The method as recited in claim 1 wherein the processing step comprises the step of estimating from the spectral data an occupied bandwidth for the unknown signal as one of the characteristics for input to the determining step.

4. The method as recited in claim 3 wherein the processing step further comprises the step of estimating from the spectral data a complementary cumulative distribution function of the peak power for the unknown signal as one of the characteristics for input to the determining step.

5. The method as recited in claim 4 wherein the determining step comprises the steps of:

inhibiting the estimating step for the complementary cumulative distribution function if the occupied bandwidth is unique to a known signal type; and

determining the identification for the signal type based upon the complementary cumulative distribution function if the occupied bandwidth is common to more than one known signal type.

6. A method of discriminating between modulation signals comprising the steps of:

selecting one of the modulation signals as a signal of interest from a displayed spectral waveform for a specified frequency range;

estimating an occupied bandwidth for the signal of interest from data representing the signal of interest;

estimating a complementary cumulative distribution function of peak power from the data for the signal of interest where the occupied bandwidth is common to more than one known signal type;

reporting an identification of the signal type as a function of the complementary cumulative distribution function.