U.S. patent application number 14/627797 was filed with the patent office on 2016-03-10 for internal line replaceable unit high intensity radiated field detector.
This patent application is currently assigned to BAE SYSTEMS CONTROLS INC.. The applicant listed for this patent is Thomas Edward Guth, Paul Hart Heiland, JR., Zain Adam Horning, Richard P. Quinlivan, Gustavo Enrique Melendez Velazquez, Peter Joseph Watson. Invention is credited to Thomas Edward Guth, Paul Hart Heiland, JR., Zain Adam Horning, Richard P. Quinlivan, Gustavo Enrique Melendez Velazquez, Peter Joseph Watson.
Application Number | 20160069942 14/627797 |
Document ID | / |
Family ID | 49476701 |
Filed Date | 2016-03-10 |
United States Patent
Application |
20160069942 |
Kind Code |
A1 |
Heiland, JR.; Paul Hart ; et
al. |
March 10, 2016 |
INTERNAL LINE REPLACEABLE UNIT HIGH INTENSITY RADIATED FIELD
DETECTOR
Abstract
Various embodiments for detecting a High Intensity Radiated
Field (HIRF) in a Line Replaceable Unit (LRU) are provided. The
internal detector may be used to test EMI filter pin connectors of
a closed LRU. For example, a method comprises setting a selecting
switch to a test connector position, thereby connecting a RF signal
generator to a testing connection cable. The method further
comprises causing the generator to generate a test signal as input
into the testing connection cable, and determining if an internal
HIRF detector has detected the signal. If the signal is detected,
the method further comprises, for each EMI filter pin connector in
the LRU, switching the selecting switch to a corresponding test
cable coupled to an EMI filter pin connector, causing the generator
to generate the test signal as input into the corresponding test
cable; and determining if the detector has detected the signal.
Inventors: |
Heiland, JR.; Paul Hart;
(Endicott, NY) ; Quinlivan; Richard P.;
(Binghamton, NY) ; Guth; Thomas Edward; (Endicott,
NY) ; Horning; Zain Adam; (Johnson City, NY) ;
Watson; Peter Joseph; (Endicott, NY) ; Velazquez;
Gustavo Enrique Melendez; (Endicott, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Heiland, JR.; Paul Hart
Quinlivan; Richard P.
Guth; Thomas Edward
Horning; Zain Adam
Watson; Peter Joseph
Velazquez; Gustavo Enrique Melendez |
Endicott
Binghamton
Endicott
Johnson City
Endicott
Endicott |
NY
NY
NY
NY
NY
NY |
US
US
US
US
US
US |
|
|
Assignee: |
BAE SYSTEMS CONTROLS INC.
Endicott
NY
|
Family ID: |
49476701 |
Appl. No.: |
14/627797 |
Filed: |
February 20, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13455777 |
Apr 25, 2012 |
8994391 |
|
|
14627797 |
|
|
|
|
Current U.S.
Class: |
324/627 |
Current CPC
Class: |
G01R 31/66 20200101;
G01R 29/0864 20130101; G01R 31/001 20130101; G01R 29/0835
20130101 |
International
Class: |
G01R 29/08 20060101
G01R029/08; G01R 31/04 20060101 G01R031/04 |
Claims
1. A method for testing EMI filter pin connectors of a closed line
replaceable unit comprising: setting a selecting switch to a test
connector position, thereby connecting a RF signal generator to a
testing connection cable, the testing connection cable being
attached to a test connector of a line replaceable unit; causing
the RF signal generator to generate a test signal as input into the
testing connection cable; determining if an internal high intensity
radiated field detector has detected the test signal, wherein if
the test signal is detected, the method further comprises, for each
EMI filter pin connector in the line replaceable unit, switching
the selecting switch to a corresponding test cable coupled to an
EMI filter pin connector; causing the RF signal generator to
generate the test signal as input into the corresponding test
cable; and determining if the detector has detected the test
signal, wherein if the test signal is detected, the associated EMI
filter pin connector coupled to the test cable is not functioning
properly.
2. The method for testing EMI filter pin connectors of a closed
line replaceable unit according to claim 1, wherein when the RF
signal generator generates the test signal as input into the
testing connection cable, if the test signal is not detected by the
internal high intensity radiated field detector, the internal high
intensity radiated field detector is determined to be not
functioning properly.
3. The method for testing EMI filter pin connectors of a closed
line replaceable unit according to claim 1, wherein the test
connector of the line replaceable unit does not have an EMI filter.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser.
No. 13/455,777, filed Apr. 25, 2012, the entire contents of which
are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to the detection of High Intensity
Radiated Fields (HIRF). More particularly, this invention relates
to a detector for detecting HIRF in a line replaceable unit.
BACKGROUND
[0003] Line Replaceable Units (LRU) are used in commercial and
military applications to provide a specific function. A line
replaceable unit includes chassis and a plurality of electronic
circuits. Some of the electronic components that form the
electronic circuits may be sensitive to HIRF. At some level of HIRF
intensity a circuit may malfunction causing the LRU to malfunction.
A typical LRU has Electromagnetic Interference (EMI) protection
such as EMI filter pins in the LRU connectors used to connect the
LRU to external cabling and careful shielding of the chassis
covers. These protection elements, however, can fail, resulting in
the electronic components being subject to the HIRF.
[0004] LRUs are tested after assembly to verify that their
operation meets specification in an Acceptance Test using factory
Test Equipment. In a similar manner, LRUs that have failed and are
repaired in the factory or in a test facility are tested to a
similar specification using the factory Test Equipment or other
test equipment that can accomplish the same testing. These tests
are referred to as Continued Airworthiness tests in the case of
equipment used on Civil Aircraft.
[0005] The testing is conducted on a closed box. That is; the unit
is connected to test equipment using cabling similar to that in the
vehicle with loads and inputs which simulate normal interfaces.
SUMMARY OF THE INVENTION
[0006] Accordingly, disclosed is a system, device and method for
verifying the integrity of the EMI filter pin connectors or LRU
shielding in a closed LRU.
[0007] Disclosed is a Line Replaceable Unit (LRU) comprising at
least one circuit board, each of the at least one circuit board
comprising circuit components mounted thereto and circuit traces, a
chassis; a built-in test section; an external connector having a
EMI filter; and an internal High Intensity Radiated Field (HIRF)
detector. The detector comprises a receiving means for receiving
HIRF and generating an Alternating Current (AC) signal proportional
to the HIRF, an RF filter configured to sample the AC signal to
create a Direct Current (DC) signal; and a detecting section
configured to compare the DC signal with a threshold and output a
result of the comparison to the built-in test section.
[0008] Also disclosed is a High Intensity Radiated Field (HIRF)
detector installed in a line replaceable unit comprising a
receiving means for receiving HIRF and generating an AC signal
proportional to the HIRF, an RF filter configured to sample the AC
signal to create a DC signal; and a detecting section configured to
compare the DC signal with a threshold and output a result of the
comparison to a built-in test section.
[0009] Also disclosed is a method for testing EMI filter pin
connectors of a closed line replaceable unit comprising setting a
selecting switch to a Test Connector position, thereby connecting a
RF signal generator to a testing connection cable, the testing
connection cable being attached to a Test Connector of a line
replaceable unit, causing the RF signal generator to generate a
test signal as input into the testing connection cable; determining
if a detector has detected the test signal. If the test signal is
detected, the method further comprises, for each EMI filter pin
connector in the line replaceable unit, switching the selecting
switch to a corresponding test cable coupled to an EMI filter pin
connector, causing the RF signal generator to generate the test
signal as input into the corresponding test cable and determining
if the detector has detected the test signal, wherein if the test
signal is detected, the associated EMI filter pin connector coupled
to the test cable is not functioning properly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] These and other features, benefits, and advantages of the
present invention will become apparent by reference to the
following figures, with like reference numbers referring to like
structures across the views, wherein:
[0011] FIG. 1 illustrates a block diagram of an example of an
internal detector in accordance with the invention;
[0012] FIGS. 2A and 2B illustrate high level schematics of examples
of the Receiving Section in accordance with the invention;
[0013] FIG. 3 illustrates an example of a circuit board having the
antenna trace according to an embodiment of the invention;
[0014] FIG. 4 illustrates a block diagram of the Processing Section
in accordance with the invention;
[0015] FIG. 5A illustrates a schematic diagram of an example of an
internal detector in accordance with the invention.
[0016] FIG. 5B illustrates test results for the example internal
detector depicted in FIG. 5A.
[0017] FIG. 6A illustrate an external view of LRU, FIG. 6B
illustrates an explode view of an LRU and FIG. 6C illustrate an
external view of the LRU showing EMI filter pin connector slots and
a Test Connector.
[0018] FIG. 7 illustrates a flow chart for a method of testing the
EMI filter pin connectors and chassis shielding during acceptance
testing; and
[0019] FIG. 8 illustrates a diagram of an example of an acceptance
Test and Continuous Airworthiness Testing systems for testing the
EMI filter pin connectors for a LRU in accordance with the
invention.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0020] Line Replaceable Unit (LRU) is a modular component used in
the military and commercial industries that is designed to be
replaced quickly at a defined location. LRUs are designed to be
removed and replaced on the flight line, hence the term "Line"
Replaceable Unit.
[0021] FIG. 1 illustrates a block diagram of an internal High
Intensity Radiated Fields (HIRF) detector 100. The HIRF environment
is applicable to equipment that is subject to extreme
electromagnetic environments and/or mission critical equipment
whose failure would be hazardous to human safety. As greater
dependence is placed upon a vehicle's electrical and electronic
systems performing functions required for safe operations, concern
has increased for the protection of these systems. Concern for the
protection of electrical and electronic systems in aircraft and
other vehicles has increased substantially in recent years due to:
[0022] Reduction in the electromagnetic shielding afforded by new
composite materials. [0023] Increased use of electrical and
electronic systems in aircraft for flight/landing systems and in
ground vehicles for propulsion and control systems. [0024]
Increased susceptibility of systems to HIRF due to increased data
bus and processor operating speeds, higher density integrated
circuits and cards, and greater sensitivities of electronic
equipment. [0025] Expansion of frequency usage above 1 GHz. [0026]
Increasing severity of HIRF environment because of an increase in
the number of RF transmitters.
[0027] HIRF requirements are applied to ensure that the electrical
and electronic systems are able to continue safe operation without
interruption, failure or malfunction, including those in LRUs.
[0028] The internal detector 100 is configured to detect HIRF
("HIRF Detector"). The HIRF Detector 100 includes a Receiving
Section 105, a RF Amplifier 110, a RF Detector/Filter 120, and a
Processing Section 125. The Receiving Section 105 is coupled to a
RF Amplifier 110. The RF Amplifier 110 is coupled the RF
Detector/Filter 120. The Processing Section 125 is coupled to RF
Detector/Filter 120. The RF Amplifier 110, the RF Detector/Filter
120 and Processing Section 125 are mounted on one or more Printed
Wire Boards. In one embodiment, the RF Amplifier 110, the RF
Detector/Filter 120 and Processing Section 125 are mounted to the
same Printed Wire Board.
[0029] The Receiving Section 105 is designed to a predetermined
frequency range. For example, the frequency range can be 100 MHz to
1 GHz. However, the design frequency range can be application
specific, e.g., different for different types of LRUs. The
Receiving Section 105 will be described in detailed with respect to
FIGS. 2A and 2B.
[0030] The gain of the RF Amplifier 110 can be set to account for
the ambient noise caused the internal electronic components.
Additionally, the gain of the RF Amplifier 110 is determined based
upon the preset detection threshold stored in the Processing
Section 125. Although, the RF Amplifier 110 is depicted in the
diagram (FIG. 1), the RF Amplifier 110 is optional and may not be
needed in all applications. The RF Detector/Filter 120 can be a
circuit containing a detection diode D1 and a RC filter section as
depicted in FIG. 5A.
[0031] In an embodiment, the Processing Section 125 can be
programmed with two modes: a testing mode and a continuous
operation mode. In the testing mode, the Processing Section 125 can
output the detection bit to an external device and in the
continuous operation mode, the Processing Section 125 outputs the
detection bit to the internal built-in test section.
[0032] FIG. 1 depicts both the test input (test signal in testing
mode) and the HIRF signal (continuous operation mode) as inputs to
the Receiving Section 105. Additionally, FIG. 1 depicts both the
bit detection signal output to the built-in test section
(continuous operation mode) and to the Test Connector 630 (as
depicted in FIGS. 6C and 8, in testing mode).
[0033] The elements of the HIRF Detector 100 can be powered from an
LRU power supply, if needed. For example, the RF Amplifier 110 can
be biased using the LRU power supply.
[0034] FIG. 2A illustrates an example of a Receiving Section 105A.
The Receiving Section 105A comprises the Receiving Elements 200,
such as an antenna array, coupling wire(s), antenna traces 310. The
Receiving Element(s) 200 can be one or more antenna wires mounted
or attached to the chassis, mounted along the chassis walls in a
three-dimensional orientation, a circuit trace embedded or etched
into a Printed Wire Board Layer 305 of a Printed Wire Board
(module) 300 or one or more of the coupling wires between two
Printed Wire Boards 300. FIG. 3 illustrates an example of Antenna
Trace 310 routed along side of internal wiring from the external
connectors to the mother board. One end of the Antenna Trace 310 is
coupled to the Summing Element 205 (Receiving Section 105A) or
Multiplexer 215 (Receiving Section 105B).
[0035] Additionally, if the Receiving Element(s) 200 is an antenna
wire mounted to the chassis, a plurality of metallic wires can be
used to create a 3-dimensional mapping to generate signals
representative of the fields in the x, y, and z directions. The
signals are then combined to detect the HIRF.
[0036] In an embodiment, antenna traces 310 can be added to each
Printed Wire Board 300 of an LRU. Therefore, even if the HIRF field
is uneven throughout the inside of the LRU, a HIRF level high
enough to cause a LRU response can be detected.
[0037] The Receiving Section 105 can be located in proximity to the
EMI filter pin connectors 625 (an example of the EMI filter pin
connectors are depicted in FIGS. 6C and 8). For example, in an
embodiment, the Receiving Section 105 can be an antenna trace 310
embedded in the closest Printed Wire Board 300. Additionally, the
Receiving Section 105 can be mounted on the chassis near the EMI
filter pin connectors. Alternatively, the Receiving Section 105 can
be located in proximity to sensitive circuit components to measure
the HIRF near the sensitive components such as analog circuits and
high gain circuits.
[0038] The Receiving Section 105A further comprises a summing
element (.SIGMA.) 205 for adding the signals received from each of
the Receiving Element(s) 200 and a Buffer 210 for buffering the
added signals. The Receiving Section 105A output is an added signal
to the RF Amplifier 110.
[0039] FIG. 2B illustrates an example of another Receiving Section
105B. The Receiving Section 105B comprises the same Receiving
Elements 200, however, instead of adding all of the received
signals, the received signals are selected one at a time by a
Multiplexer 215. Each selected signal is successively buffered by
Buffer 210. The Multiplexer 215 repeatedly outputs one selected
signal at a time to the Buffer 210. Each signal received from the
Receiving Elements 200 is selectively output for each cycle. The
Receiving Section 105B outputs the currently selected signal to the
RF Amplifier 110. Receiving Section 105B allows for each signal to
be examined by the Processing Section 125.
[0040] FIG. 4 illustrates a block diagram depicting an example of
the Processing Section 125. In the example of the Processing
Section 125 depicted in FIG. 4, the Processing Section 125
comprises a Comparator 400, a Sampler 405 and a Persistence
Detector 410. In an embodiment, the Processing Section 125 includes
a storage device (not shown) for storing at least one detection
threshold. Since each LRU reacts differently to a HIRF, the
detection threshold varies based on the type of LRU and the
electronic components mounted to the print wire boards 300.
Therefore the detection threshold can be application specific. The
detection threshold also can be remotely adjusted after assembly,
as necessary. In this embodiment, the storage device may also
include a threshold adjustment for performing the functionality
described herein.
[0041] The Processing Section 125 receives the output of the RF
Detector/Filter 120 (showing in FIG. 4 as input) and the Comparator
400 compares this input with the detection threshold. If the
received output is higher than the detection threshold, the
Comparator 400 outputs a signal indicating a positive detection to
the Sampler 405. For example, the Comparator 400 can output a
"high" signal value. If the input is less than the detection
threshold, the Comparator 400 outputs a signal indicating a
negative detection to the Sampler 405. For example, the Comparator
400 can output a "low" signal value.
[0042] The Sampler 405 periodically samples the output of the
Comparator 400. The sample rate is preset. The sample rate can be
every 30 seconds. However, the sample rate can be application
specific. Furthermore, in an embodiment, the sample rate can be
remotely adjusted after assembly, as necessary. In this embodiment,
the storage device (not shown) may also include a sample rate
adjustment for performing the functionality described herein. If
the Sampler 405 receives a positive detection signal during the
sample period, e.g., a "high" signal, the Sampler 405 outputs a
positive detection signal to the Persistence Detector 410. If the
Sampler 405 receives a negative detection signal during the sample
period, e.g., a "low" signal, the Sampler 405 outputs a negative
detection signal to the Persistence Detector 410.
[0043] The Persistence Detector 410 is configured to determine if
the positive detection signal received from the Sampler 405 occurs
for a period of time where the HIRF signal can cause damage. In an
embodiment, the Persistence Detector 410 counts the number of
consecutive positive detection signals received from the Sampler
405 and compares the counted number with a threshold. If the
counted number is greater than the threshold, the Persistence
Detector 410 outputs a positive detection bit to the built-in test
section (in continuous operation mode) or to the Test Connector 630
(in testing mode). The built-in test section can be mounted on the
same Printed Wire Board 300. In another embodiment, the Persistence
Detector 410 counts the number of positive detection signals
received from the Sampler 405 within a preset period of time. If
the counted number is greater than the threshold, the Persistence
Detector 410 outputs a positive detection bit to the built-in test
section or the Test Connector 630. In another embodiment, the
Persistence Detector 410 tracks the number of positive detection
signals received in a period of time and the number of negative
detection signals received within the same period of time. The
Persistence Detector 410 separately adds the number of positive
detection signals and the negative detection signals and then
subtracts the total number of negative detection signals from the
total number of positive detection signals to obtain a net positive
detection value. If the net positive detection value is greater
than the threshold, the Persistence Detector 410 outputs a positive
detection bit to the built-in test section (or the Test Connector
630).
[0044] While FIG. 4 depicts the Comparator 400, Sampler 405 and the
Persistence Detector 410 separately, these components can be
integrated into a single processor. The processor can be a
microprocessor or a CPU. Additionally, the functionality of the
Comparator 400, Sampler 405 and persistence detection 410 can be
implemented using a Programmable Array Logic (PAL), Programmable
Logic Device (PLD), Field Programmable Array Logic (FPGA) or an
Application Specific Integrated Circuit (ASIC).
[0045] The Processing Section 125 is powered from the LRU Power
Supply (not shown).
[0046] The HIRF Detector 100 can be used during initial testing,
such as acceptance testing, during continuous operation and during
maintenance procedure such as continued airworthiness (CAW)
tests.
[0047] FIG. 5A illustrates a schematic diagram of an example of
HIRF Detector 100. FIG. 5B depicts simulated and measured test
results for this detector. A signal having a known signal strength
was input. The output voltage was measured using a voltmeter. The
simulated results substantially correlate with the measure
voltages. As can be seen from FIG. 5B, the frequency response for
the detector is relatively flat over measured frequency range.
[0048] FIG. 6A illustrates an external view of an example of an LRU
600. FIG. 6A depicts the external chassis shielding 605. FIG. 6B
illustrates an external exploded view of the same LRU 600. The
external view illustrates multiple Printed Wire Boards 300. The
front panel 610 and rear panel assembly 615 and the side panels 620
form a housing for the Printed Wire Boards 300. The front panel
610, rear panel assembly 615, and side panels 620 collectively form
the chassis shielding 605. The Printed Wire Boards 300 attached to
slots in the rear panel assembly 615.
[0049] FIG. 6C illustrates an external view of a second example of
an LRU 600A. A panel comprises a plurality of EMI filter pin
connectors 625 and a Test Connector 630. During testing, the Test
Connector 630 is covered with a metallic cover 635.
[0050] The HIRF Detector 100 is sensitive to higher than normal
intruding EMI fields from external sources. Each LRU 600 also
includes a built-in test section (not shown).
[0051] Each Printed Wire Board 300 has electronic component mounted
thereto. These electronic components are configured to perform the
functionality of the LRU, e.g., LRU 600. Additionally, according to
certain aspects of the invention, one or more of the Printed Wire
Boards 300 also includes electronic components that are dedicated
to detect HIRF and output a signal to a built-in test section. If a
HIRF is detected, there is a high likelihood that either one of the
EMI filter pin connectors 625 and/or the chassis shielding 605 have
failed. The HIRF Detector 100 provides a closed-box testing.
[0052] A typical LRU, e.g., LRU 600, is tested using an extensive
qualification and acceptance testing that exposes the units and a
model of their interconnections cabling to high amounts of
electromagnetic energy (RF energy), representative of a real world
exposures that the units can and will be exposed during service.
The tests use various test equipment to evaluate the levels of
energy and the response of the unit.
[0053] The test implements an Acceptance Test Procedure
(ATP)/Continuous Airworthiness Procedure. The tests are required to
be performed with the LRUs 600 closed and in a ready-for-delivery
configuration. The HIRF Detector 100 is used to determine the
integrity of the LRU 600 related to an exposure of the RF
energy.
[0054] FIGS. 7 and 8 illustrate the testing procedure and test
setup, respectively.
[0055] The test setup 800 comprises an external test RF Signal
Generator 805, a Connector Switch 810, a plurality of External Test
Cables 815.sub.N and a Test Connector 630. The Connector Switch 810
comprises a plurality of switching positions and will selectively
couple the test signal generated by the RF Signal Generator 805 to
each of the External Test Cable 815 and the Test Connector 630 via
the connector testing cable 631. As depicted in FIG. 8, the
Connector Switch 810 has four switch positions (illustrates by the
dots). Three of the switching positions are used to couple the
three External Test Cables 815 (three EMI filter pin connectors
625.sub.N) to the RF Signal Generator 805. One of the switching
positions is used to couple the Test Connector 630 to the RF Signal
Generator 805. The Connector Switch 810 will need to have one more
switching position than the number of EMI filter pin connectors
625.sub.N. Each EMI filter pin connector 625 has a corresponding
External Test Cable 815 coupled to it. As depicted, there are three
EMI filter pin connectors 625.sub.1-3 and three external test
cables 815.sub.1-3. FIG. 8 illustrates a portion of the External
Test Cable being exposed to show the internal test cable wires and
the coupling resistors (test cable wires 816). The External Test
Cables 815.sub.1-3 have LRU connectors at one end and at the other
end each wire in the cable is terminated in a coupling resistor.
The other terminal of each of the isolation resistors associated
with a given cable is connected together and connected to the
output amplifier. Each external test cable 815 is similarly
fitted.
[0056] The Test Connector 630 is coupled to the internal HIRF
Detector 100. The Test Connector 630 is not fitted with EMI
filters. When not in use, the area where the Test Connector 630 is
located is capped with the metallic cover 635 for EMI shielding.
The Test Connector 630 is capped during testing to present the test
frequency signal being leaked into the LRU, e.g., 600A.
[0057] The output of the internal HIRF Detector 100 is sent to a
test equipment computer (the computer is not shown in FIG. 8).
However, the output of the internal HIRF Detector 100 is
illustrated as Detection Signal 830.
[0058] As depicted in FIG. 8, the LRU under test, e.g., LRU 600A,
comprises three internal circuit modules (wire boards 300.sub.1-3),
three EMI filter pin connectors 625.sub.1-3 and a rear panel
assembly 615. The EMI filter pin connectors 625.sub.1-3 are coupled
to the rear panel assembly 615 via cables 817.sub.1-3.
[0059] FIG. 7 illustrates a flow chart of an example of a testing
method. The testing method will be described in conjunction with
the test setup depicted in FIG. 8. However, the testing method is
not limited to the test setup 800 depicted in FIG. 8 and can be
conducted using other testing setups.
[0060] At step 700, the Connector Switch 810 is set to the Test
Connector 630, which couples the RF Signal Generator 805 to the
Test Connector 630. At step 705, the LRU, e.g., 600A having the
internal HIRF Detector 100, is excited with the test frequency
signal the internal HIRF Detector can be on one or more of the
Internal Circuit Modules 300.sub.1-3 (Printed Wire Board). The
power level of the test frequency signal is predetermined and
controlled. The RF Signal Generator 805 is set to the predetermined
frequency and amplitude for the Test Connector input. At step 710,
the Processing Section 125 compares the output of RF
Filter/Detector 120 with the preset threshold. The Processing
Section 125 compares a digital value of the test frequency signal
with the preset threshold. The digital value is generated from the
received test frequency signal. The HIRF Detector 100 should
indicate that HIRF has been detected. At step 715, a determination
is made if the HIRF Detector 100 detected the HIRF by evaluating
the Detection Signal 830 on the test equipment computer. If the
HIRF Detector 100 detected the HIRF, then the testing proceeds ("Y"
at step 715). This test validates that the HIRF Detector 100
functions properly.
[0061] At step 720, the Connector Switch 810 is set to one of the
External Test Cables, e.g., 815.sub.1, which couples the RF Signal
Generator 805 to the external test cables 815.sub.1. For each
external test cable 815, the LRU with the internal HIRF Detector
100 is excited with the test frequency signal at step 725. At step
730, the Processing Section 125 compares the output of RF
Filter/Detector 120 with the preset threshold. At step 730, the
Processing Section 125 outputs the Detection Signal 830. At step
735, a determination is made if the HIRF Detector 100 detected the
HIRF by evaluating the Detection Signal 830 on the test equipment
computer. If all of the EMI filter pin connectors 625 are
functioning properly no response from the HIRF Detector 100 is
expected ("N" at step 735). If the HIRF Detector 100 registers a
HIRF intrusion, the EMI filter pin connector 625 is faulty ("Y" at
step 735) and must be replaced or repaired (step 737).
[0062] Steps 720-735 are repeated for each EMI filter pin
connection 625. After step 735, a determination is made if there
are any untested EMI filter pin connectors 625 (step 740). If there
are untested EMI filter pin connectors ("Y" at step 440), the
process returns to step 720. If not, ("N" at step 740), the process
is done and all of the EMI filter pin connectors 625 are
functioning properly (step 742).
[0063] If at step 715, the test signal is not detected by the HIRF
Detector 100, the HIRF Detector 100 is faulty ("N" at step 715) and
should be examined for further evaluation (step 717).
[0064] Various aspects of the present disclosure may be embodied as
a program, software, or computer instructions embodied or stored in
a computer or machine usable or readable medium, which causes the
computer or machine to perform the method when executed on the
computer, processor, and/or machine. A computer readable medium,
tangibly embodying a program of instructions executable by the
machine to perform various functionalities and methods described in
the present disclosure is also provided.
[0065] The computer readable medium could be a computer readable
storage medium or a computer readable signal medium. Regarding a
computer readable storage medium, it may be, for example, a
magnetic, optical, electronic, electromagnetic, infrared, or
semiconductor system, apparatus, or device, or any suitable
combination of the foregoing; however, the computer readable
storage medium is not limited to these examples. Additional
particular examples of the computer readable storage medium can
include: a portable computer diskette, a hard disk, a magnetic
storage device, a portable Compact Disc Read-Only Memory (CD-ROM),
a Random Access Memory (RAM), a Read-Only Memory (ROM), an Erasable
Programmable Read-Only Memory (EPROM or Flash memory), an
electrical connection having one or more wires, an optical fiber,
an optical storage device, or any appropriate combination of the
foregoing; however, the computer readable storage medium is also
not limited to these examples. Any tangible medium that can
contain, or store a program for use by or in connection with an
instruction execution system, apparatus, or device could be a
computer readable storage medium.
[0066] The computer instructions may be provided to a processor of
a general purpose computer, special purpose computer, or other
programmable data processing apparatus to produce a machine, such
that the instructions, which execute via the processor of the
computer or other programmable data processing apparatus, create
means, devices, units, or sections for implementing the
functionality specified.
[0067] The Detector may be any type of known or will be known
systems such as, but not limited to, a virtual computer system and
may typically include a processor, memory device, a storage device,
input/output devices, internal buses, and/or a communications
interface for communicating with other computer systems in
conjunction with communication hardware and software, etc.
[0068] The terms "element", "interface", "section", "device" or
"unit" as may be used in the present disclosure may include a
variety of combinations of fixed and/or portable computer hardware,
software, peripherals, and storage devices. The Detector or system
may include a plurality of individual components that are networked
or otherwise linked to perform collaboratively, or may include one
or more stand-alone components.
[0069] The function(s) described herein may occur out of the order
noted in the figures or text including in the reverse order or
concurrently (or substantially concurrently) depending upon the
functionality involved.
[0070] The embodiments described above are illustrative examples
and it should not be construed that the present invention is
limited to these particular embodiments. Thus, various changes and
modifications may be effected by one skilled in the art without
departing from the spirit or scope of the invention as defined in
the appended claims.
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