Description
VERMIN REPELLENT ARRANGEMENT AND METHOD FOR REPELLING AT
LEAST ONE TYPE OF VERMIN
The invention is related to a vermin repellent arrangement
and to a method for repelling a vermin, particularly a speci
fied type of vermin.
While in middle or northern European countries vermin and
pests are often considered as annoyance only, in many other
countries vermin are a vector for spreading diseases, causing
significant loss on human lives and severe damage to economy.
For example, malaria, which is a mosquito-borne infectious
disease of humans, remains a scourge in tropical and sub
tropical regions, including much of sub-Saharan Africa, Asia
and Americas killing around one million people each year. The
disease itself is spread by a mosquito and in particularly by
the bites of female mosquitoes feeding on the blood of human
beings. Although vaccine is currently tested, it may be unre
liable and/or too expensive for many people to afford, par
ticularly in those regions most affected by the disease.
Tsetse flies on the other hand are considered to be a vector
for the human African trypanosomiasis, the so-called sleeping
sickness .
Up to this date, current prevention techniques have not been
able to eradicate or significantly control the spreading of
the diseases by reducing the number of mosquitoes. Recent
controlled studies conducted to date by independent investi
gators found that vermin being a vector of disease agents
comprised merely a few percentage of the daily catch or an
entire season. Therefore, an area wide and indifferent dis
persion or disposition of repellent may be ineffective and/or
harm also useful insects. As such, there is still a need for
arrangement and methods providing improved repellent capabilities
to reduce the risk for humans to be bitten.
This and other objects are solved by the presently independ
ent apparatus and method claims. Embodiments and further as
pects are subject matter of the dependent claims. In this respect
the term "vermin" reflects any type of pest or more
general any type of insect, particularly but not limited to
flying insects.
The vermin repellent arrangement proposes detection means for
detecting a specific pre-defined type of vermin in a first
area. Particularly, the detection means comprise means for
acoustically detecting a vermin in said first area and pro
viding a first detection signal in the response thereto.
Evaluation means coupled to the detection means are adapted
to receive the first detection signal and provide a repellent
control signal in response to an evaluation. For instance,
these means may evaluate the first detection signal and a
reference signal, wherein the reference signal is assigned to
at least one pre-defined type of vermin. If a concurrence or
correlation is determined between the first detection signal
provided by the detection means and the reference signal, the
pre-defined type of vermin is considered to be positively
identified and a dosage of a repellent compound is released
into the area the vermin is currently staying in.
The detection of a specific pre-defined type of vermin in a
specified area reduces the overall amount of repellent dosage
to be vaporized and prevents or at least reduces killing of
useful insects.
In a further embodiment a low power scent system may be used
to provide a concentrated scent of human sweat, carbon diox
ide or blood vapor to attract a pre-defined type of vermin,
for instance female mosquitoes to a pre-ordained area. Alter
natively a different compound may be used to attract a type
of vermin. Once within the area, the attracted vermin may be
identified by the detection and evaluation means. For this
purpose, the detection means may comprise a microphone, par
ticularly a stereo microphone arranged to detect the sound of
the wing beats of vermin in the pre-ordained area. The use of
a stereo microphone allows obtaining direction or distance of
the detected vermin. In this respect, the term "sound" re
flects any acoustic information generated by at least one
type of vermin.
The evaluation means may evaluate this sound and compare the
detected sound with a pre-defined sound, for instance with a
wing beat sound of a specific type of vermin. The evaluation
means may comprise a filter having a passband characteristics
corresponding to a wing beat sound of the at least one pre
defined type of vermin. The evaluation means make use of the
fact that each type of vermin may comprise a different spec
tral characteristic of its wing beat sound. Even female and
male vermin may comprise different characteristics and as
such they can be identified by their wing beat sound charac
teristic .
In an embodiment the evaluation means are adapted to compare
at least a portion of a frequency spectrum of the detection
signal with a frequency spectrum of a wing beat sound of the
at least one pre-defined type of vermin. In another embodi
ment the evaluation means may comprise a comparator to pro
vide the repellent control signal in response to a comparison
of the processed and preferably filtered detection signal and
the reference signal. The reference signal may be a reference
frequency spectrum. If the processed and filtered detection
signal exceeds the reference signal, the detected type of
vermin corresponds to the pre-defined type and is further
considered to be at a distance in reach of the repellent dosage.
The repellent dosage may be vaporized into a preferred direc
tion within the pre-ordained area covered by the detection
means. In this respect the term "vaporizer" means every device
or apparatus capable and adapted for releasing an amount
of compound into an area. It may comprise a nozzle, sprayer,
atomizer and the like driven by mechanical, electrical, elec
tro-mechanical or other means.
To attract the pre-defined type of vermin, the arrangement
may comprise a storage coupled to a second vaporizer to pro
vide a vapor of a compound attractive to the at least one
pre-defined type of vermin. A small dosage may be vaporized
to attract the pre-defined type of vermin in response to an
attraction control signal. Said attraction control signal may
be provided within a pre-defined time period or in response
to a general detection of vermin within the pre-ordained
area .
In a further embodiment, the arrangement may comprise addi
tional detection means, particularly optical or acoustical
detection means to detect vermin in a second area. Said sec
ond area may at least comprise a portion of the pre-ordained
area. A second detection signal is provided in response
thereto. The attraction control signal may now be provided by
the evaluation means in response to the second detection sig
nal .
A method for repelling at least one type of vermin comprises
detecting sound generated by a vermin in a pre-ordained area
and providing a recorded signal thereof. In particular, the
sound may be the wing beat sound or any sound generated by
wings or its elytron. The recorded signal is evaluated and
may be compared with a reference signal, wherein the refer
ence signal is assigned to at least one pre-defined type of a
vermin. Upon correlation or consistency between the recorded
signal and the reference signal a repellent dosage is vaporized
within the pre-ordained area.
In a further aspect detecting sound of the vermin comprises
detecting the wing beat sound of the vermin in a pre-ordained
area and in response thereto vaporizing a dosage of a compound
attractive to the at least one pre-defined type of ver
min .
Detecting the vermin comprise an optical detection or an
acoustical detection.
As an alternative or in addition to vaporizing a dosage of a
repellent compound, the identified vermin could be eliminated
by use of a small laser or the proboscis of the vermin could
be sealed as the vermin tries to draw a fluid from a trap.
For this purpose, a membrane could be used which clocks the
proboscis of the vermin.
The present invention is now explained in greater detail with
a reference to the accompanying drawings, in which:
Figure 1 illustrates a first exemplary embodiment of a vermin
repellent arrangement,
Figure 2 shows an embodiment of the evaluation means accord
ing to the embodiment of figure 1 ,
Figure 3 illustrates a second embodiment of the arrangement
according to the proposed principle,
Figure 4 shows an embodiment of the processor according to
the embodiment of figure 3 ,
Figure 5 shows another embodiment of the vermin repellent ar
rangement,
Figure 6 illustrate yet another embodiment of a vermin repel
lent arrangement,
Figure 7 illustrates a first embodiment of a method for re
pelling at least one type of vermin and,
Figure 8 shows a second embodiment of a method for repelling
at least one type of vermin.
The following examples and embodiments are illustrated models
and do not reflect correct dimensions or specific arrange
ments unless otherwise stated. The different aspects of the
embodiments can be combined with each other by a person
skilled in the art. For example the evaluation means shown in
the figures are not restricted to the respective embodiment.
Rather, they or their features can be combined by person
skilled in the art. It should be noted that elements or fea
tures with similar functions bear similar or same reference
signs .
Figure 1 illustrates an embodiment of a vermin repellent ap
paratus according to the present invention. The apparatus 1
comprises two storage containers 11 and 12, wherein the first
storage container 11 comprises a vermin repellent compound.
In this example, the vermin repellent compound may be chosen
to specifically repel a pre-defined type of vermin. As such,
the compound may be vermin specific. The second storage 12
comprises a compound, which is attractive to the pre-defined
type of vermin. For example storage container 12 may comprise
a chemical compound similar to human sweat, carbon dioxide
and blood. If vaporized via a vaporizer 7 said chemical com
position may attract an insect, for example a female mosquito
to shield arrangement 5 and the area covered by the arrange
ment. The attractant area may contain an artificial face or
other body part, where the vermin can hover and/or land.
Shield arrangement 5 also comprises vaporizer 6 , which is
coupled to the first storage container 11. Shield 5 also com
prises on one side a stereo microphone 8 , which is coupled to
a processor 10. Processor 10 evaluates signals from stereo
microphone 8 . Microphone 8 is particularly sensitive in a
frequency range, which comprises frequency portions of a
sound, e.g. a wing beat sound of a specified type of vermin
to be repelled. Stereo microphone 8 allows not only to identify
the type of vermin via recordation of the wing beat
sound, but also to evaluate direction and distance to vapor
izers 6 and 7 . For this purpose, processor 10 receives the
signal of microphone 8 at input terminal 100. Processor 10
evaluates the signal received by stereo microphone 8 and com
pares the received signal with one or more reference signals.
Those reference signals correspond to sounds of the pre
defined type of vermin. For example, the reference signals
may be a reference frequency spectrum.
For instance, stereo microphone 8 records the wing beat of a
vermin, particularly a mosquito. Likewise processor 10 pro
vides a reference signal corresponding to the wing beat sound
of the mosquito. Upon comparison of the recorded signal and
the reference signal processor 10 evaluates and identifies
the type of vermin within the area covered by stereo micro
phone 8 and vaporizers 7 and 6 . If the recorded wing beat
corresponds to the pre-defined type of vermin, processor 10
will send an attraction control signal to storage 12 to re
lease a further dosage of attractive compound. If successful,
the vermin closes the distance to vaporizer 7 , which may
cause an increased level of the wing beat sound recorded by
stereo microphone 8 or any other pre-defined change. Processor
10 evaluates via recorded signal again and upon evalua
tion, for instance upon evaluating direction and distance
processor 10 provides a repellant control signal at output
106 to storage 11. In response thereto storage 11 releases a
repellent compound via vaporizer 6 .
Processor 10 as well as all other electrical devices are sup
plied by a battery 13 coupled to supply terminal 105. Instead
of a battery 13, any other energy storage or power supply may
be used. For example, a solar cell could be used to charge a
battery pack for use of the arrangement during night time.
By acoustically identifying the predetermined type of vermin,
for example a female mosquito or a tsetse fly or any other
vermin potentially causing harm to human beings or spreading
diseases, the overall amount of repellent dosage can be re
duced significantly. Particularly, the repellent dosage will
be vaporized only at a time, at which the identified vermin
is close to vaporizer 6 . For attracting the respective type
of vermin the second vaporizer 7 with the second storage 12
is used.
Figure 2 shows an example of processor 10 which is capable of
identifying several different types of vermin. Processor 10
comprises a first input terminal 100 which is coupled to the
stereo microphone to receive an acoustic detection signal.
Said detection signal is applied to a filter 210 having a
passband characteristic. The passband is selected to be in a
range also comprising the sounds, e.g. the wing beat sounds
of the types of vermin to be repelled. The filtered signal is
applied to an analog to digital converter 250 to obtain a
digital signal thereof. The digital signal is applied to an
FFT to obtain the frequency portions of the recorded and filtered
signal. The output of the FFT 240 is coupled to a com
parator 230. A second input terminal of comparator 230 is
connected to storage 220. The memory storage comprises stored
data representing one or more reference frequency spectrum of
pre-defined types of vermin to be repelled. For instance memory
220 may comprise data representing the frequency spectral
characteristic of a female mosquito or a tsetse fly and the
like. It may also comprise spectral characteristics of other
types of vermin for statistical purposes. Any characteristic
can be stored in memory 220 via interface 110.
In response to a comparison of the frequency characteristic
of the recorded signal with the stored signal in memory 220,
processor 10 provides a control signal at terminal 106 to re
lease or spray a respective dosage of the repellent compound.
Memory 220 is also coupled to terminal 107 for releasing an
attractive compound within pre-defined time periods.
Figure 3 shows an alternative embodiment of a vermin repel
lent arrangement according to the proposed principle. The ar
rangement comprises a shield 5 with an open area 51 and a releasable
container 50. Container 50 comprises any elimi
nated/dead vermin after operation of the arrangement. Close
to container 50, at the back side 52 of shield 5 , the vapor
izer 7 is arranged. Vaporizer 7 is coupled to controllable
valve 70 for releasing and spraying an attractive compound
stored in storage 12.
Second vaporizer 6a is arranged vis-a-vis container 50 and
directed into an area of shield 50 above container 50. Vapor
izer 6a is connected to controllable valve 60 for releasing a
small amount of a repellent dosage from storage 11. A vermin
within the area is directly sprayed and eliminated and drops
into container 50.
A first microphone 8a is arranged close to area 51 and the
open end of shield 5 . Microphone 8a is connected to input
terminal 100a of processor 10. A second microphone 8b is ar
ranged close to area 53 and coupled to a second input termi
nal 100b of processor 10. Processor 10 and the microphones as
well as all other electrical devices are supplied by a battery
13, which also includes a solar cell for recharging the
battery .
In operation of the arrangement, the wing beat sound of a
vermin close to area 51 is recorded via microphone 8a and re
ceived by processor 10. Processor 10 evaluates this signal
and evaluates whether the recorded sound corresponds to a respective
wing beat of a predetermined type of vermin. If so
it activates valve 70 via a respective control signal through
terminal 107 to release a small amount of attractive dosage
into area 53 of shield 5 . The vermin in area 51 is now at
tracted by said attractive compound into area 53. Upon moving
from area 51 to area 53, the level of the recorded wing beat
is decreasing at microphone 8a while at the same time in
creasing at microphone 8b.
The wing beat sound may be identified again by processor 10
and upon exceeding a pre-defined threshold, processor 10 pro
vides a control signal at terminal 106 to open valve 60. A
small amount of repellent dosage is released and sprayed into
area 53, the area which now presumably contains the vermin.
The sprayed vermin is eliminated and drops into container 50.
In this respect, figure 4 illustrates an embodiment of proc
essor 10 which provides an identification circuitry for a
specific type of vermin. As mentioned before, a pre-defined
type of vermin can be identified by a specific characteristic
of its sound, e.g. its wing beat sound. Such wing beat sound
may comprise a characteristic fundamental frequency and har
monics. For example, wing beat sound of a female mosquito is
different from a wing beat sound of a male mosquito or other
vermin. To identify such wing beat, processor 10 comprises
two filters 310 and 311, each of them having a bandpass char
acteristic. Filter 310 is coupled to terminal 100b to filter
the recorded signal of microphone 8b, while filter 311 is
connected to input terminal 100a.
The passband of each filter corresponds to the frequency
spectrum of the sound of a female mosquito. The output termi
nal of filter 311 is connected to a first input terminal of a
first comparator 313. A second input terminal of the first
comparator 313 is coupled to a reference signal source 314.
First comparator 313 is connected to output terminal 107 for
providing the control signal to release a small dosage of at
tractive compound. The output of the first comparator 313 is
also coupled to a delay line 317 and to a logic OR gate 316.
The output of filter 310 is connected to a first input termi
nal of a second comparator 312. A second input terminal of
the second comparator 312 is coupled to the reference signal
source 314. The output of the second comparator is connected
to an input of logic AND gate 315 the output of that logic
gate providing the control signal for releasing an amount of
the repellent compound.
In operation, a signal recorded by microphone 8a is applied
to input terminal 100a and filtered via bandpass filter 311.
Comparator 313 provides a respective output signal upon com
parison of the filtered signal with a first reference signal
Vref 1 . If the filtered signal exceeds the threshold of reference
signal Vrefl, comparator 313 provides a control signal
at terminal 107 to release the attractive compound via vapor
izer 7 into area 53. Further, the signal is applied to logic
OR gate 316 and to delay unit 317. The delay unit 317 is used
to take the time period into account, which is required for
the chemical compound to dispense within area 53 and to at
tract the vermin located close to area 51 into area 53.
When flying or generally moving from area 51 to area 53, the
signal level recorded by microphone 8a decreases and the sig
nal level may drop below the threshold of Vrefl. However,
logic gate 316 will still provide a logic high signal at its
output due to the delay unit 317 indicating a vermin is in
proximity .
At the same time, the level of the recorded signal at termi
nal 100b increases and is filtered by filter 310. The filtered
signal is now compared at comparator 312 with a second
threshold reference signal Vref 2 . Upon exceeding the second
reference signal Vref2, comparator 312 provides a respective
output signal to logic AND gate 315. If both input signals at
gate 315 are considered high, gate 315 generates the control
signal to spray a repellent dosage into area 53, thereby
eliminating any vermin within the area.
The use of two microphones 8a and 8b provides the possibility
to obtain direction and movement information of a predetermined
type of vermin. Of course, instead of two different mi
crophones 8a and 8b also a stereo microphone can be used as
well .
Further, it is also possible to replace microphone 8a with
any other kind of identification and detection means. For ex
ample, microphone 8a could be replaced by an optical detec
tion means for detecting any type of the vermin within area
51. To this extent, the passband characteristic of filter 311
could be implemented in a more general and not vermin type
specific way to generally detect plurality types of vermin.
Figure 5 illustrates another embodiment of the present inven
tion, in which shield 5 has the shape of a hollow cylinder
with an opening area 51a facing downwards. Close to opening
area 51a one or more optical detectors 9 are arranged for op
tical detection of a vermin. In the side wall of the hollow
cylinder a stereo microphone 8b is arranged close to an area
covered by a vaporizer 6a. The stereo microphone may detect
not only any sound itself, but also direction. Optionally, a
second vaporizer 7a for spraying an attractive compound into
that area is inserted vis-a-vis stereo microphone 8b.
Processor 10 of this arrangement comprises a first input ter
minal 100b for signals recorded by stereo microphone 8b and a
second input terminal 100c for receiving detection signals
from optical sensors 9 . Processor and evaluation means 10
further comprise an amplifier 420 coupled to input terminal
100c for amplifying an optical detection signal. Amplifier
420 is connected upstream to low pass filter 421 for filter
ing and identifying the vermin within area 51a. Filter 421
provides a signal to a comparator 422 which compares the op
tical detection signal with a reference signal. Upon exceeding
the threshold comparator 422 provides a control signal to
switch 418, said switch connected to terminal 100b. Option
ally, it provides a control signal to valve 70 for releasing
a dosage of an attractive compound into the hollow cylinder.
Upon providing the control signal by comparator 422, filter
410 and comparator 412 are activated. Further, switch 418 is
closed thereby coupling terminal 100b to filter 410. Filter
410 is a bandpass filter filtering the signal of the recorded
wing beat of the vermin and compares the filtered signal in
comparator 412 with a reference signal. In response to the
comparison valve 60 and a vaporizer 6a is activated releasing
a dosage of a repellent compound.
The control signal outputted by comparator 422 reduces the
overall power consumption, as the microphone 8b as well as
other portions of evaluation means 10 are activated only upon
detecting a vermin within area 51a by means of comparator
422. Hence a battery life can be extended.
In this embodiment, two optical sensors 9 are used to detect
a vermin within area 51a. Of course, the optical sensors can
be replaced by an acoustical sensor, for instance a microphone
or any other means to detect movement or a vermin
within area 51a.
In addition to the chemical attraction means with vaporizer
7a, valve 70 and storage 12, other attraction means like optical
attraction means can be used as well. For instance, an
infrared source can be arranged onto the side wall providing
an infrared signal similar to the human emitted infrared
spectrum.
Figure 6 illustrates an alternative for vermin repellent ar
rangement. In this embodiment, screen 5 with an open area 51
facing downwards comprises one or two microphones 8 , 8a ar
ranged such that they are able to record any sound signals
generated by vermin within area 51.
At the upper end of area 51, a membrane 9a is arranged form
ing a capacitive element with upper layer 91. For this pur
pose, membrane 9a is coupled to terminal 100c of evaluation
means 10b. In addition, vaporizer 7a for releasing an attractive
compound is coupled to storage 12b and to evaluation
means 10b for receiving a respective release control signal.
A further vaporizer or spraying element 6b is arranged close
to membrane 9a and connected to storage 11a. That storage
comprises a compound which may also include components at
tractive to the pre-defined type of vermin, like for instance
the female mosquito. However, the compound also comprises a
material potentially sealing the proboscis of the vermin.
If microphones together with processor 10 detect and posi
tively identify a vermin, and more specifically a predeter
mined type of vermin, evaluation means 10b generate an at
traction control signal releasing a small dosage of an attractive
compound from storage 12a via vaporizer 7a. At the
same time, membrane 9a and facing upper layer 91 are applied
with a respective voltage. If the vermin now tries to reach
the potential food source, it may land on membrane 9a stick
ing its proboscis through membrane 9a. The vermin on the surface
and the proboscis may cause the change in the capaci
tance between membrane 9a and plate 91, which can be detected
by evaluation means 10b. Upon such detection, the evaluation
means generate a control signal for releasing a small amount
of a compound from storage 11a via vaporizer 6b. The compound
is drawn by the vermin potentially sealing its proboscis. For
this purpose, the compound may comprise an adhesive or any
other material clocking the proboscis while the vermin tries
to draw food or blood through membrane 9a.
Figure 7 illustrates an embodiment of the method for repel
ling a vermin.
Often preparation of the apparatus in respective area, for
example in a human' s dormitory, sleeping room or any other
kind of closed space is done in step SI before activating the
apparatus. The battery or energy storage is fully loaded and
the device activated.
The apparatus releases in step S2 a small amount of attractant
dosage into the air attracting any vermin for which the
attractant compound is assigned to. After spraying the attractant
into the area, the microphone is activated. The microphone
listens and records any signal and particularly po
tential sound, for example a wing beat of vermin entering a
pre-ordained area, substantially defined by the microphone's
sensitivity. If after some time in step S4 no sound was re
corded, a further small amount of attractive compound would
be released.
If, however, a wing beat sound is recorded, the method will
proceed with step S5 by identifying the sound and comparing
the recorded signal with one or more reference signals. Those
reference signals are assigned to sounds generated by prede
termined types of vermin, for instance the wing beat sound of
a female mosquito. For example, the one or more reference
signals may be reference frequency spectrums .
If the comparison proves unsuccessful, the vermin is consid
ered not to be of the pre-defined type and the method contin
ues with step S8. Waiting for some time might be useful to
reduce the probability of faulty or incorrect measurements
and decrease the amount of a sprayed attractant compound.
If a pre-detected type of vermin is identified in step S6 the
repellent compound is sprayed into the area thereby eliminat
ing the vermin in step S7. After some time in step S8, a new
small amount of attractant compound is sprayed and the method
is repeated with step S2 .
In this embodiment, the attractant compound is released peri
odically to attract specific types of vermin into pre-defined
area covered by the repellent means. A repellent compound is
only sprayed into the area after a predetermined type of ver
min is identified to be in that area. Nevertheless, the
amount of attractant compound used can be reduced.
To this extent, Figure 8 shows a respective example. After
preparation of the arrangement, a solar power cell charges in
step S10 a battery pack and stores solar energy for later use
and particular during night time. The apparatus is activated
with use of a light sensor and the microphone records sound
in step Sll. Said recorded sound is compared with a reference
signal, for instance corresponding to a reference sound,
which may in turn correspond to a vermin's wing beat. If the
comparison shows no correlation in step S12, a new sound is
recorded and step Sll repeated.
If a recorded sound corresponds to vermin wing beat, the
method continues with step S13 releasing a small dosage of an
attractant compound. The compound is selected to be attractive
to a specific type of vermin to be repelled. After the
release of the attractant compound in step S13, some time is
passed and then any sound is recorded again. The recorded
sound is compared with a signal representing a predetermined
sound, for example a wing beat generated by the predetermined
type of vermin.
If a comparison proves successful, repellent means in step
S16 are activated to repel the vermin. For example, a small
amount of repellent compound may be released in the area in
which the vermin is located, an optical sensor may be used to
eliminate the vermin using a small laser or any other repel
lent or elimination method may be used.
After step S16, some time is waited in step S17 and then the
method is repeated starting again with step Sll. If the com
parison in step S15 shows no correlation, meaning that the
recorded sound does not seem to be generated by the predetermined
type of the vermin, there is no need to activate the
repellent means. Therefore, the method continues with step
Sll after a predetermined time period has passed in step S17.
The present invention provides a possible solution to prevent
an arbitrary killing of beneficial insects. It cannot only be
used to repel vermin potentially dangerous for humans but re
pel any type of sound producing vermin or pests. Further, the
presented apparatus and method can attract vermin away from
humans in the area they may be sleeping.
The small amount of insecticide or repellent compound reduces
the contamination and exposure to humans or beneficial in
sects. Further, specific repellent or attractive compounds
can be used which may be suitable for children or particularly
sensitive persons. The small current source needed for
the arrangement provides access to locations without regular
power supply.
Claims
1 . Vermin repellent arrangement, comprising
a repellent storage (11) coupled to a first vaporizer (6,
6a) adapted to provide a repellent dosage into a first
area (51, 53) in response to a repellent control signal;
means for acoustically detecting a vermin in said first
area (51, 53) and providing a first detection signal in
response thereto;
evaluation means (10, 10b) adapted to receive said first
detection signal and comprising a comparator (312, 412) to
provide the repellent control signal in response to a com
parison of at least a portion of a frequency spectrum of
the first detection signal with a reference frequency
spectrum of sound caused by at least one pre-defined type
of vermin.
2 . The arrangement according to claim 1 , wherein the means
for acoustically detecting comprise a microphone (8, 8a,
8b) , particularly a stereo-microphone arranged close to
the first vaporizer (6) .
3 . The arrangement according to any of claims 1 to 2 , wherein
the evaluation means comprise filter means (310, 311, 410)
having a passband characteristic corresponding to sound,
particularly a wing beat sound caused by the at least one
pre-defined type of vermin, the filter means (310, 311,
410) being arranged upstream to the comparator (312, 412) .
4 . The arrangement according to any of claims 1 to 3 , wherein
the vaporizer (6a) is adapted to vaporize the repellent
dosage into preferred direction within the area (53) .
The arrangement according to any of claims 1 to 4 , further
comprising :
an attraction storage (12) coupled to a second vaporizer
(7) to provide a vapour of a compound attractive to the at
least one pre-defined type of vermin in response to an at
traction control signal provided by the evaluation means.
The arrangement according to any of claims 1 to 5 , further
comprising detection means (8a, 9), particularly optical
or acoustical detection means to detect a vermin in a sec
ond area (51), said second area at least comprising a por
tion of the first area (53) and to provide a second detec
tion signal in response thereto.
The arrangement according to claim 5 or 6 , wherein the
evaluation means is adapted to provide the attraction con
trol signal in response to the first or the second detec
tion signal.
The arrangement according to any of claims 1 to 7 , wherein
a gender of the at least one pre-defined type of vermin is
female .
Method for repelling at least one type of vermin, compris
ing :
detecting sound caused by a vermin in a pre-ordained area
and providing a recorded signal thereof;
performing a Fourier transformation on the recorded signal
to obtain at least a portion of the frequency spectrum of
the recorded signal.
comparing the portion of the frequency spectrum with a
reference signal, said reference signal being a reference
frequency spectrum and being assigned to at least one pre
defined type of vermin; and
releasing a dosage of repellent into the pre-ordained area
in response to the comparison.
10. The method of claim 9 , wherein the recorded signal is
filtered prior to the Fourier transformation with a filter
having a passband characteristic corresponding to sound
caused by the at least one type of vermin.
11. The method of claim 9 or 10, wherein comparing comprises
comparing a level of the portion of the frequency spectrum
with a reference level.
12. The method of any of claims 9 to 11, wherein detecting
sound comprises detecting a wing beat sound caused by the
vermin .
13. The method of any of claims 9 to 12, further comprising:
releasing a compound into an area covering at least partly
the pre-ordained area, said compound being attractive to
the at least one type of vermin.
14. The method of claim 13, further comprising:
detecting vermin, particularly detecting vermin by optical
or acoustical means before releasing the compound in re
sponse thereof.