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Radar A radar device is a device that emits electromagnetic waves and evaluates the reflected “echo” for various criteria's. For a better understanding, it can be compared with light beams. A flashlight produces a light cone and the eye detects light that is reflected from objects. Unlike the eye, however, a radar antenna can´t recognize an image, but only slices. For this reason, radar antennas rotate at the airport and then puts together many slices to a complete picture. RADAR = Radio Detection and Ranging

Radar

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Page 1: Radar

Radar

A radar device is a device that emits electromagnetic waves and evaluates the reflected “echo” for various criteria's.

For a better understanding, it can be compared with light beams.A flashlight produces a light cone and the eye detects light that is reflected from objects.

Unlike the eye, however, a radar antenna can´t recognize an image, but only slices. For this reason, radar antennas rotate at the airport and then puts together many slices to a complete picture.

RADAR = Radio Detection and Ranging

Page 2: Radar

BioRadar

The BioRadar was specially developed for detecting minimal alternating signals in moderate depths.

Much effort is made to filter out the static reflections and evaluate only the altering reflections.

Compared with light all objects in the room are ignored and only the altering reflections are visible. If there is no moving object in the room, nothing is visible. If something moves, it lights up suddenly.

Page 3: Radar

BioRadar

Unlike in geology the BioRadar does not search for static objects such as faults and caverns but for signals of living organisms.

Heartbeat and respiration are the difference between a victim and other objects.

Due to the Doppler effect any movement causes the reflected wave to experiences a slight change in its frequency.

Compared with light we search for objects, that slightly vary in color of its reflection.

Page 4: Radar

BioRadar

In a second stage, the moving reflections are evaluated with regard to biometric pattern.A broken water pipe will be shown due to its movement.But the movement pattern does not correspond to a heartbeat or respiration.

In the software you can set how long the pattern must match biometric criteria to activate the "Live possible“ message.

Page 5: Radar

application

The BioRadar does not produced a visual image. A depth determination is not implemented.

The electromagnetic waves can be greatly reflected.The military tries to develop materials with low radar signature at great expense.An echo captured by the radar antenna can have performed a veritable rollercoaster ride. The echo can come back via multiple reflections by objects and layers.

If we could transform the BioRadar signal into an image, then that would be as reliable as what we see in a mirror cabinet. Only if the positions and angles of all reflecting surfaces are known, we could determine where the object actually is located.

It is essential to practice with the BioRadar and to be able to read the site."Reading" skills and practice are main keys for success.

Page 6: Radar

Location of live patterns

Necessary conditions:

reflection

motion:Chaotic (limbs, body) Occurrence : indefiniteduration: Indeterminate intensity: undefined?

Periodical (breathing, heartbeat) Occurrence: Always Duration: 3 to 6 seconds breathing Heartbeat 0.5 to 1 second

Intensity: determined by the size of the reflecting surfacePenetrable obstacleDistance law, the energy per unit area decreases with r ² With reflection on the way back?Damping absorption law - exponentially - frequency dependent

The antenna emits a 55° cone

Page 7: Radar

Initial measurement:Can I see anything because of the physics here?I can already tell from the outside whether the signals are reflected?Where could be a victim?Is there any hind of other search techniques? (Mobile phone tracking, viewing, search dogs ...)

Signals found:What pattern do the signals show? (chaotic, periodic)Could it be self-reflection?Can a measurement from another angle confirm the signals? No signals:To massive obstacles?Distance to large?

Location of live patterns

Page 8: Radar

Diplay

Display of the received echo.Compared with acoustics, this would equal the volume. A selection of pitch or even rhythms is not yet done.

The two curves are different viewing angle to the echo coming back polarized due to the reflection. Depending on the polarization the wave may even appear as a flat line.

neither the overlay nor the volume are important.

Page 9: Radar

Display

In this diagram the echo is decomposed into its frequencies (low frequency bottom, high frequency top)The brightness indicates how strong the echo of a certain frequency is.In addition, the response over time is shown.The "amount" of echoes of a frequency over time is the chart on the next slide.

The grey lines show the areas where the software recognizes signal patterns corresponding to biometric conditions.The information in the diagram indicates that a significant signal with a frequency of 0.42 Hz was recognized.The signal was seen in total for 44 seconds and uninterrupted for 27 seconds.

Page 10: Radar

Display

Here, the received echo is decomposed into its frequencies.But the height of the peaks does not correspond to the effective “volume ", but as a sum over the time.

Page 11: Radar

Display

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Page 12: Radar

Energie

100 50 25 12,5 6,25 3,125 1,5625 0,78125

25% return

0,01% return

0,0001% returnbig damping by distance

low power by out of center

Power Spread of powermax. in center, less at edge

of cone

50% reflection

3,125% reflection