MC Countermeasures Inc. - Operator Interface

Operator Interface / Data Recording

A real-time operator interface application is available (Microsoft Windows 2000/XP operating system required) that polls the status of the various PRED channels and displays the ranges of the PRI, Pulse Width, RF, Stagger position and frame time to the operator. In addition, information about the state of the emitters present is communicated to the operator through the use of colour coding. An operator can use this display to monitor the emitters that are present in the selected band or to actively assign emitters to an ECM channel (eg DRFM, SOR, VCO, etc) for appropriate countermeasures.

Although the PRED does not need any a priori emitter information in order to establish a track, any known emitter parameters can be used in order to make a signal identification. A built-in database that matches emitter parameters to emitter modes specified by the user makes it easier to categorize emitters; rather than simply displaying measured parametric values, the software can attempt an identification based on the information in the database and display an emitter name and mode. The database entry window below shows 6 emitter mode entries based on ranges of PRI, Pulse Width, RF and number of stagger positions. Using the database the operator is able to concentrate on the task at hand without having to refer to manual look-up approaches in order to identify signals. The database allows for the use of as little or as much information as is on hand. In this example, frame time and duty cycle are not used for identification.

Emitter Mode Database Window

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Using the “Predictor Control” window of the GUI shown below the operator is able to configure the PRED. This window allows the user to select:

which mode the PRED will be operated in (either “Emitter Select” or “Timeshare”),
what form of Adaptive Prediction will be used (none, Single (Adaptive) or Multiple (MAP)),
PRI and RF tracking tolerance,
RF Agility Bandwidth ,
RF Reject Filters,
Manual select modes for the output (jam) channels.

In normal operation the operator would not need to use this window but it does allow for adjusting PRED parameters if needed. It is more likely that this window would be used in a lab environment. It can also be used to de-interleave and send emitters to multiple ECM assets if they exist.

PRED Control Window

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Figure 14 shows the display when a 2 (output)-channel PRED is exposed to an environment consisting of 6 scanning emitters. Using this PRED architecture specific emitters can be assigned to a DRFM and others to a VCO or countermeasures architecture For example if the system has a DRFM and a VCO or second DRFM depending on the system architecture. The display consists of 3 main windows. The top window shows all of the emitters that are currently active but not being jammed. The 2 lower windows show the status of the 2 output (jam) channels. In this case, only Output Channel 1 is active and it is currently jamming an emitter which has been designated “st5 – Mode: 1”.

Colour coding is used to convey important information to the operator:

· RED – indicates a non-scanning emitter track. In this example emitter mode “st1 – Mode:1” is non-scanning emitter.

· Green – indicates an active scanning emitter track. In this example there are 2 active scanners; one is undefined while the other is emitter mode “st4 – Mode:1”. It should be noted that although a track may be undefined, the emitter is being tracked (without a priori information) and can be selected for ECM.

· YELLOW – indicates a new emitter track. Here “st0 – Mode:1” has just appeared.

· GREY – indicates an emitter than cannot be acquired but that can be jammed using adaptive predictive techniques. In this case, the PRED has been able to adaptively predict and identify emitter mode “st2 Mode:1”.

The ranges of the measured parameters (PRI, Pulse Width, RF, Number of Stagger Positions and Frame Time) as well as the emitter mode ID (including an estimate of the accuracy of the ID) is presented to the operator. The operator is free to turn off selected measurements in order to de-clutter the display.

When the measured parameters do not appear to match an emitter described in a database entry, the Emitter Name is presented as “(undefined)”. If the operator is able to identify this mode or if he would like to name it some way, he is able to add the emitter description to the database by clicking on the “(undefined)” name and selecting the “Add to Database” button. This causes a window to open which is populated with the measured parameters. This new entry can then be named and saved back into the database.

The real-time interface can serve 2 roles. It can be used simply to monitor the environment – essentially performing a situation awareness (SA) function or it can be used to actually assign emitters to the jammer for countermeasures through a simple point-and-click operation. If multiple emitter modes are selected for countermeasures, the software automatically calculates the ranges required for the selection process and programs the PRED accordingly. A manual over-ride provision allows the operator to set any other ranges he chooses. ECM output #1 has been configured to jam only emitter “st5 – Mode: 1”; however by simply changing the values in the PRI, RF, PW, Stagger and frame time registers, the operator is able to easily redefine the jam parameters if necessary. This allows the operator to discontinue jamming on one radar for instance and focus the jammer onto another specific emitter.

Real-time monitor window

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Operator Interface Features in Development

The information being displayed to the operator is being re-organized in order to simplify the display and at the same time provide additional useful information including:

the accuracy of predictions for each emitter mode being tracked.
the accuracy of prediction in the ADAPTIVE ACQUISITION channel when a full track cannot be initiated.
check boxes for selecting and de-selecting emitter modes for jamming.
check boxes to prevent certain emitter modes from being displayed.
check boxes to automatically assign RF Reject bands to certain emitter modes.
Indication of RF Agility in an emitter.
The ability to manually change ECM techniques in each jam channel.

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Instrumentation/Data Collection

The PRED Evaluation station is capable of recording many useful parameters to help instrument PRED operation. This instrumentation function can be used to ascertain what emitters are present, what emitters have been selected for jamming, etc.

The figure below shows some data that was captured from the PRED in the lab to show that it was identifying and properly locking onto a specific emitter. The full trace covers several minutes of data but in this view we have zoomed in on only a couple of seconds.

Sample Recorded Data

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The PCT was used to create an environment that consists of 6 emitters that are up simultaneously. The first trace (Gen Video) is the detected video being fed into the PRED from the jammer showing illuminations from the 6 scanning emitters. The following 6 traces (bit0 - bit5) come from the PCT and show the output from each of the 6 PCT generators that actually make up the Gen Video signal. They are only shown here to demonstrate that the PRED actually tracks the correct signal of interest. Of course in a normal operational environment you would not have access to these signals.

In this example the PRED has been programmed to respond only to Gen2 (which is a 5 element- 25 position stagger PRI pattern). We have programmed the PRED to respond with an emitter mode (EM_ID) of 8. Each time that the PRED locks onto this emitter we see that PRI Lock 1 goes HI and that EM_ID indicates mode 8 as desired. Cursors can be used to examine the scans to show that this is happening on each scan of the radar (1 scan - 2 illuminations are shown here). The second illumination is interesting here in that we can see that not only was Emitter2 active but so was Emitter1 and the PRED actually had to de-interleave each pulse in real-time.

Time stamps (the large numbers (21,755 to 56,882) above the traces) indicate when this data was captured. A GPS receiver will be integrated with the PRED in this application in order to time stamp the data with accurate UTC time.

Other information could be gathered if desired so that the analysis can be as simple or as complex as desired. Since the instrumented outputs are configured through a field programmable gate array, changes can be made quickly and easily. Data can be captured in 2 modes - a slow time mode (several hrs of recording) that attempt to instrument what emitters are present and what the jammer does in response to those emitters and a higher speed mode (several minutes of recording depending on pulse density) in which we capture data on a pulse to pulse basis for post-mission analysis (or even playback using the PCT in the Evaluation Station.