31-08-2012, 03:05 PM
A MODERN MICROWAVE LIFE DETECTION SYSTEM FOR HUMAN BEING BURIED UNDER RUBBLE
[attachment=33021]
ABSTRACT
“Thousand of persons killed as a cause of earthquake”. The above words aren’t the headlines of the newspaper but such
news come after the disaster destroyed the field. The disaster in the New York City at ‘World Trade Center’ claimed lives of
more than 5000 people. It was said if survivors has been found and rescue earlier the numbers of victims have been lower.
There is no end to the number of lives lost as the result of such disasters as landslides, collapsed tunnels and avalanches.
The microwave life detection system is develope for the search and rescue of victims trapped under the rubble of collapsed
building during the earthquake or other disasters. The proposed system utilizes L-band frequency which is able to detect
respiratory and heart fluctuations. The operation principle is based on Doppler frequency shift of the electromagnetic wave
reflected from the buried victim. The schematic diagram of microwave Transmitting/Receiving (T/R) and clutter
cancellation subsystem are included in this report. In this report various parts of a microwave life detection system such as
antenna, directional coupler, and splitter has been discussed. By advent of this system the world death rate as a cause of an
earthquake may decrease to greater extent.
INTRODUCTION
Most of the victims of earthquake or other natural
disasters in the various parts of the worlds are trapped
under rubble of the collapsed buildings. A detection
of the victims can save his life. As in the radar
application, the phase of the incident wave can be
changed due the body vibrations. Depending upon
this fact “A Revolutionary System to Detect Human
Being Buried under the Rubble” used to trap the
buried victims under earthquake rubble or collapsed
buildings by the utilization of microwave radio
frequency has been design.
Principle of Working:
The principle of detection is firstly, microwave is
sent through rubble to detect vital signs of life.
Microwave is having the property to penetrate
through barriers and would reflect back from some
objects. These objects include humans. When the
beam hits the body, the signal reflected with an
additional modulation created by movement of heart
and lungs. So, the reception of modulated signals
shows the presence of alive human inside the rubble.
With the modulated signal there are some signal
(commonly known as clutter signal) which are
reflected from the immobile object such as rubble or
debris. Thus in order to maintain a high sensitivity
for this application, the clutter wave reflected from
the rubble or the surface of the ground has to be
cancelled as thoroughly as possible. For this an
automatic clutter cancellation system is used. A
microwave life detection system operated on the
radio frequency was proposed in the 1985 [3]. This
system detects the body oscillations occur due the
breathing and heartbeat fluctuations. The system
includes the additional subsystem to cancel the
unwanted signals receive from the motionless objects
such as rubble.
LITERATURE REVIEW
Images of events causing damage in which people
have been trapped or buried under rubble serve as
constant reminders of the vulnerability of the places
where we live and work. To conduct rapid rescue
operations, emergency forces all over the world need
timely information on the exact position of people
trapped or buried under rubble, information on the
risk of collapse of debris and standardized
intervention procedures as well as information on the
state of the victims’ health.
History
Collapse of man-made structures, such as buildings
and bridges, occur with varying frequency across the
world. In such a case, survived human beings are
often trapped in the cavities created by collapsed
building material. The concept of microwave life
detection system was emerged with the development
in the systems for rescue operation. Initial dogs were
used to detect presence of human then acoustic
detectors and robot radar come into existence. But
these systems are having major drawbacks.
Working of life detection system:
The circuit diagram of the microwave life-detection
system is shown in Fig. 2. A phase-locked oscillator
generates a very stable EM wave at 1150 MHz with
an output power of 400mW (25.6 dBm). This wave is
fed through a 10-dB directional coupler and a
circulator before reaching a radio-frequency (RF)
switch, which energized the dual antenna system
sequentially. The 10-dB directional coupler branches
out one-tenth of the wave (40 mW) which is then
divided equally by a 3-dB directional coupler. One
output of the 3-dB directional coupler (20 mW)
drives the clutter cancellation circuit and the other
output (20 mW) serves as a local reference signal for
the double-balanced mixer. The wave radiated by an
antenna penetrates the earthquake rubble to reach a
buried human subject.
CONCLUSION
A life-detection system with a microprocessor-based
automatic clutter cancellation subsystem can be
invented for special rescuing robots. This system can
operates at 2-G Hz and it will be used remotely to
detect the breathing and heartbeat signals of alive
subjects through rubble or some other barriers about
3ft in thickness. The microprocessor-based automatic
clutter- canceling increases the efficiency of system.
The clutter canceller uses an adjustable attenuator
and phase shifter to cancel the transmitting power
leakage from the circulator and background reflection
clutter to enhance the detecting sensitivity of the
weak vital signals.
We believe that through the development of similar
and related techniques for life detection system, it
will be possible to overcome the current fundamental
problems in detecting buried victims and save many
precious lives.
[attachment=33021]
ABSTRACT
“Thousand of persons killed as a cause of earthquake”. The above words aren’t the headlines of the newspaper but such
news come after the disaster destroyed the field. The disaster in the New York City at ‘World Trade Center’ claimed lives of
more than 5000 people. It was said if survivors has been found and rescue earlier the numbers of victims have been lower.
There is no end to the number of lives lost as the result of such disasters as landslides, collapsed tunnels and avalanches.
The microwave life detection system is develope for the search and rescue of victims trapped under the rubble of collapsed
building during the earthquake or other disasters. The proposed system utilizes L-band frequency which is able to detect
respiratory and heart fluctuations. The operation principle is based on Doppler frequency shift of the electromagnetic wave
reflected from the buried victim. The schematic diagram of microwave Transmitting/Receiving (T/R) and clutter
cancellation subsystem are included in this report. In this report various parts of a microwave life detection system such as
antenna, directional coupler, and splitter has been discussed. By advent of this system the world death rate as a cause of an
earthquake may decrease to greater extent.
INTRODUCTION
Most of the victims of earthquake or other natural
disasters in the various parts of the worlds are trapped
under rubble of the collapsed buildings. A detection
of the victims can save his life. As in the radar
application, the phase of the incident wave can be
changed due the body vibrations. Depending upon
this fact “A Revolutionary System to Detect Human
Being Buried under the Rubble” used to trap the
buried victims under earthquake rubble or collapsed
buildings by the utilization of microwave radio
frequency has been design.
Principle of Working:
The principle of detection is firstly, microwave is
sent through rubble to detect vital signs of life.
Microwave is having the property to penetrate
through barriers and would reflect back from some
objects. These objects include humans. When the
beam hits the body, the signal reflected with an
additional modulation created by movement of heart
and lungs. So, the reception of modulated signals
shows the presence of alive human inside the rubble.
With the modulated signal there are some signal
(commonly known as clutter signal) which are
reflected from the immobile object such as rubble or
debris. Thus in order to maintain a high sensitivity
for this application, the clutter wave reflected from
the rubble or the surface of the ground has to be
cancelled as thoroughly as possible. For this an
automatic clutter cancellation system is used. A
microwave life detection system operated on the
radio frequency was proposed in the 1985 [3]. This
system detects the body oscillations occur due the
breathing and heartbeat fluctuations. The system
includes the additional subsystem to cancel the
unwanted signals receive from the motionless objects
such as rubble.
LITERATURE REVIEW
Images of events causing damage in which people
have been trapped or buried under rubble serve as
constant reminders of the vulnerability of the places
where we live and work. To conduct rapid rescue
operations, emergency forces all over the world need
timely information on the exact position of people
trapped or buried under rubble, information on the
risk of collapse of debris and standardized
intervention procedures as well as information on the
state of the victims’ health.
History
Collapse of man-made structures, such as buildings
and bridges, occur with varying frequency across the
world. In such a case, survived human beings are
often trapped in the cavities created by collapsed
building material. The concept of microwave life
detection system was emerged with the development
in the systems for rescue operation. Initial dogs were
used to detect presence of human then acoustic
detectors and robot radar come into existence. But
these systems are having major drawbacks.
Working of life detection system:
The circuit diagram of the microwave life-detection
system is shown in Fig. 2. A phase-locked oscillator
generates a very stable EM wave at 1150 MHz with
an output power of 400mW (25.6 dBm). This wave is
fed through a 10-dB directional coupler and a
circulator before reaching a radio-frequency (RF)
switch, which energized the dual antenna system
sequentially. The 10-dB directional coupler branches
out one-tenth of the wave (40 mW) which is then
divided equally by a 3-dB directional coupler. One
output of the 3-dB directional coupler (20 mW)
drives the clutter cancellation circuit and the other
output (20 mW) serves as a local reference signal for
the double-balanced mixer. The wave radiated by an
antenna penetrates the earthquake rubble to reach a
buried human subject.
CONCLUSION
A life-detection system with a microprocessor-based
automatic clutter cancellation subsystem can be
invented for special rescuing robots. This system can
operates at 2-G Hz and it will be used remotely to
detect the breathing and heartbeat signals of alive
subjects through rubble or some other barriers about
3ft in thickness. The microprocessor-based automatic
clutter- canceling increases the efficiency of system.
The clutter canceller uses an adjustable attenuator
and phase shifter to cancel the transmitting power
leakage from the circulator and background reflection
clutter to enhance the detecting sensitivity of the
weak vital signals.
We believe that through the development of similar
and related techniques for life detection system, it
will be possible to overcome the current fundamental
problems in detecting buried victims and save many
precious lives.