Electricity: measuring and testing – Fault detecting in electric circuits and of electric components – For fault location
Reexamination Certificate
2007-05-01
2007-05-01
Hirshfeld, Andrew (Department: 2858)
Electricity: measuring and testing
Fault detecting in electric circuits and of electric components
For fault location
C324S534000, C324S535000
Reexamination Certificate
active
11266538
ABSTRACT:
An apparatus for detecting concealed surveillance devices coupled to a transmission line uses either a time domain or frequency domain reflectometry operation to locate any impedance anomalies on the transmission line and a non-linear junction detection operation to classify the located impedance anomalies as semiconductor or non-semiconductor based anomalies. The reflectometry operation utilizes the reflection of a test signal to determine the distance to any reflecting impedance anomalies on the transmission line that may be indicative of an electronic device being coupled to the transmission line. The non-linear junction detection operation then compares the amplitudes of re-radiated second and third harmonics of a transmitted fundamental frequency signal to determine if the reflecting impedance anomalies are the result of a semiconductor based non-linear junction. A DC bias voltage and a balanced load may be added to the transmission line to enhance the line's response to the test signals. Any unidentified semiconductor based anomalies are manually inspected to determine if they represent convert surveillance devices.
REFERENCES:
patent: 3631484 (1971-12-01), Augenblick
patent: 4053891 (1977-10-01), Optiz
patent: 4063229 (1977-12-01), Welsh et al.
patent: 4123749 (1978-10-01), Hartmann et al.
patent: 4331957 (1982-05-01), Enander et al.
patent: 4413254 (1983-11-01), Pinneo et al.
patent: 4439769 (1984-03-01), Masak
patent: 4471344 (1984-09-01), Williams
patent: 4547724 (1985-10-01), Beazley et al.
patent: 4586048 (1986-04-01), Downie
patent: 4595915 (1986-06-01), Close
patent: 4700179 (1987-10-01), Fancher
patent: 5068614 (1991-11-01), Fields et al.
patent: 5191343 (1993-03-01), Danzer et al.
patent: 5414410 (1995-05-01), Davies et al.
patent: 5881132 (1999-03-01), O'Brien et al.
patent: 5990791 (1999-11-01), Endreasen et al.
patent: 5994905 (1999-11-01), Franchville
patent: 6057765 (2000-05-01), Jones et al.
patent: 6097798 (2000-08-01), Albers et al.
patent: 6163259 (2000-12-01), Barsumian et al.
patent: 6177801 (2001-01-01), Chong
patent: 6466649 (2002-10-01), Walance et al.
patent: 6744854 (2004-06-01), Berrier et al.
patent: 6759853 (2004-07-01), Butler
patent: 6765527 (2004-07-01), Jablonski et al.
patent: 6816575 (2004-11-01), Lowell et al.
patent: 6897777 (2005-05-01), Holmes et al.
patent: 6934655 (2005-08-01), Jones et al.
patent: 6937944 (2005-08-01), Furse et al.
patent: 2004/0036478 (2004-02-01), Logvinov et al.
Barsumian Bruce R.
Jones Thomas H.
Liter Charles A.
Hirshfeld Andrew
Valone Thomas
LandOfFree
Surveillance device detection utilizing non linear junction... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Surveillance device detection utilizing non linear junction..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Surveillance device detection utilizing non linear junction... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3732541