Note: Descriptions are shown in the official language in which they were submitted.
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Description
Cable, method for producing a cable, and method for
locating a cable
Prior Art
Manufacturing data which is obtained during the
production of a cable has until now been stored in the
form of manufacturing documentation or in computers
separately from the cable. Manufacturing data such as
this includes, for example, the type of cable, the
number of individual fibers, the type of the individual
fibers or a unique identification for the cable or the
individual fibers.
Sequential meter lengths are normally applied to the
cable sheath, in particular during production of the
cable, by means of ink printers, hot-stamp film or
length strips composed of paper or plastic. The length
of the section of the cable arranged in between is
defined by two of the meter lengths. Once the cable has
been laid, the information about the meter length is no
longer accessible.
Since a cable that has been laid in the ground has a
corrugated profile, reliable association of the length
of a cable section laid between two points with a
distance between the two points, as determined by way
of example from a location plan, is not possible.
The document DE 198 14 540 Al proposes a cable and a
measurement apparatus for determination of the cable
length, with the cable being fitted at defined length
positions with data storage media, such as
transponders, a barcode or magnetic strips, which can
be read by a data reader. The advantage of a
transponder or a magnetic strip is that the contents of
these data storage media can be changed by writers.
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Other information can thus also be recorded, in
addition to length information.
When using transponder arrangements in a cable, care
must be taken to ensure that the transponder
arrangements are protected against external influences
on the cable, for example against mechanical loads, for
instance resulting from impacts, or against the ingress
of moisture. Furthermore, the transponder arrangements
must be arranged such that they are not directly
subjected to the high temperatures which occur, for
example, during an extrusion process, during cable
manufacture.
The object of the invention is to provide a cable in
which a transponder device is integrated in the cable
such that it is protected as well as possible against
influences during production of the cable and during
operation of the cable, in order to provide extensive
and accurate information about the cable at the
manufacturer's works, and to simplify access to this
information. A further object of the invention is to
provide a method for manufacturing a cable, in which a
transponder device is integrated in the cable such that
it is protected as well as possible against influences
during production of the cable and during operation of
the cable, in order to provide extensive and accurate
information about the cable at the manufacturer's
works, and to simplify access to this information. A
further object of the invention is to specify a method
for location of a point on a cable such as this.
The object is achieved by a cable having the features
of Claim 1, by a method for manufacturing a cable
having the features of Claim 16, and by a method for
location of a cable having the features of Claim 21.
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The cable has a transponder arrangement which has a
memory for storing digital data and has a transponder
for wire-free transmission of digital data, a cable
sheath, which surrounds the transponder arrangement, a
transmission element, which is surrounded by the cable
sheath with the transponder arrangement being arranged
between the transmission element and the cable sheath,
a braiding which surrounds the transmission element and
the transponder arrangement, holds the transponder
arrangement on the transmission element, and very
largely protects the transponder arrangement against
temperature influences.
A transponder arrangement such as this is normally
referred to by the expressions RFID Tag (Radio
Frequency Identification Tag), Smart Chip or Green Tag.
The transponder arrangement uses an antenna to receive,
for example, a radio pulse from a communication
appliance, in particular a reader or a writer, and
sends back fixed or variable information. The
transponder arrangement is integrated in the physical
structure of a cable or of a core during production
and, in a label, contains all of the functions which
are required for storage and for interchange of the
digital data. The cable or the core may contain
electrical or optical conductors and may be intended
for transmission of power or for transmission of
messages. Passive transponder arrangements which obtain
the electrical power required for their operation from
the signals from the communication appliance have a
virtually unlimited life and are insensitive to dirt,
grease and static charging. A typical memory volume for
a transponder arrangement such as this is, for example,
2 MB (megabytes) . The digital data may, for example,
include manufacturing information or information which
is dependent on the length of a cable section. The data
can be read from the memory, or written to the memory,
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without the use of wires and without a visual link, at
a high transmission rate. The data can be interchanged
irrespective of the location, that is to say without
the communication appliance and the transponder
arrangement being in a defined relative position with
respect to one another. However, the direction to the
transponder arrangement can also be found, and it can
also be located, by means of a suitably designed
communication appliance when it is necessary to
determine the position of the transponder arrangement
in order to determine the route of the cable or of the
conductor.
Storage of the information on the cable at the
manufacturer's works avoids difficulty in the
association between the cable and the information from
the manufacturer about the cable, such as those which
can occur when the data is stored separately from the
cable.
After manufacturing the cable, the cable sheath also
intrinsically provides the transponder arrangement with
more protection than the support element.
Introduction of the transponder arrangement into the
cable core which is surrounded by the cable sheath
ensures that the transponder arrangement is protected
against the temperatures which occur during extrusion
of the sheath.
Attachment of the transponder arrangement to a
transmission element makes it easier to introduce the
transponder arrangement into the sheath extruder.
The braiding separates the transponder arrangement from
the cable sheath, thus effectively protecting it
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against the temperatures which occur during extrusion
of the sheath.
The cable preferably comprises an elongated support
element in the form of a strip, to which the
transponder arrangement is attached, or in which it is
mounted.
The support element may be a plastic strip or may have
a round cross section. The transponder arrangement may
be encapsulated in the support element. This allows the
transponder arrangement to be protected against dirt,
grease and electrostatic charging even during
production of the cable.
The braiding preferably contains holding elements in
the form of threads.
The holding elements in the form of threads can be
extruded from a melt.
The holding elements in the form of threads preferably
contain Kevlar fibers or glass fibers.
The Kevlar fibers or glass fibers can also be used for
strain relief.
The transmission element preferably has an optical
waveguide, and the cable is preferably formed only from
dielectric materials in a surrounding area which
surrounds the transponder arrangement.
If no metal is arranged in the vicinity of the antenna
of the transponder arrangement, then digital data which
has been stored in the transponder arrangement can be
read over a relatively long distance by a communication
appliance.
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The transmission element preferably comprises a metal
line.
The disadvantageous influence of the metal line can be
partially compensated for by suitable orientation of
the antenna of the transponder arrangement.
The cable preferably has a cable sheath in which the
transponder arrangement is embedded. In this case, the
cable sheath is preferably composed of two layers,
which are produced by an extrusion process. The
transponder arrangement is fitted to a first sheath
layer. A second sheath layer is then extruded over it.
A transponder arrangement may be subject to
temperatures of about 200 C. Temperatures of about 85 C
occur during sheath extrusion. For example, the
transponder arrangement can thus be pushed into the
cable sheath while it is still hot.
The cable preferably has a transmission element which
has a sleeve, with the transponder arrangement being
surrounded by the sleeve.
A transponder arrangement could thus be arranged within
a transmission element. In this case, it would also be
feasible for a cable to contain a plurality of such
transmission elements, each having a corresponding
transponder arrangement. The internal configuration of
a cable is reflected by all of the information which
can be read from the cable.
The transponder arrangement preferably has a processor
to which electrical power and a system clock can be
supplied via the transponder and which is designed to
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read digital data from the memory, and to send the
digital data via the transponder.
The digital data received via the transponder can be
written to the memory preferably by the processor.
By way of example, the transponder arrangement memory
may be written to for the first time before, during or
after production. Furthermore, the digital data
contained in the memory can be updated after a cable
repair.
A length section of the cable has a length, and the
digital data in the memory preferably contains
information about the length of the length section.
The meter length of a cable can be read by a
communication appliance, without the use of wires. The
length of the section of cable arranged between two
different points can be determined by reading the meter
lengths at these two different points.
The digital data in the memory preferably contains a
first feature, a second feature is preferably defined
by further digital data received by the transponder,
and the digital data in the memory can preferably be
read from the memory only if the first feature and the
second feature match.
The first feature may, for example, be a security
feature which is stored in the transponder arrangement
at the manufacturer's works. A keyword which is
transmitted by a communication appliance is checked on
the basis of the security feature, and the stored data
is or is not transmitted as a function of the result of
the check. This allows the stored digital data to be
protected against access by unauthorized persons.
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The first feature preferably contains the information
about the length of the length section of the cable.
The first feature may include the meter length stored
in the transponder arrangement. The second feature may
include a test value. The transponder arrangement may
be designed to respond to a broadcast signal only if
the test value and the stored meter length match. This
makes it possible to implement an anti-collision
protocol in order to deliberately ensure a response
from one, and only one, of a plurality of transponder
arrangements which are located within a response range
of a communication appliance.
The transponder arrangement is preferably in the form
of a passive system. In this case, there is no need to
provide any power supply device on a chip which
contains the transponder arrangement. The power for
operation of the transponder arrangement is taken
directly from an electromagnetic field, for example the
field of the communication appliance.
In one development of the invention, the transponder
arrangement is in the form of an active system which
has its own supply device for provision of a power
supply for the transponder arrangement. The power
supply for the transponder arrangement is in this case
preferably provided by a rechargeable supply device.
According to a further feature of the invention, the
rechargeable supply device is a rechargeable battery.
The rechargeable supply device can preferably be
recharged by wire-free means.
The transponder arrangement therefore does not require
any exposed connections in order to supply electrical
power or in order to interchange digital data, can be
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introduced into the cable in a sealed form, is not
subject to any wear, and requires no maintenance.
Transponder arrangements having a rechargeable battery
can be used if the transponder is intended to have a
relatively long range or the cable contains
transmission elements with metal lines.
The use of a rechargeable battery ensures that the
functions of the transponder device are available to a
user without any time constraint. If the rechargeable
battery has been discharged or if, as a result of the
transponder already having been accessed a number of
times, a state of charge is reached at which it is no
longer possible to read or write information from or to
a memory in the transponder arrangement, the supply
device can be recharged in order to provide the power
supply for the transponder arrangement. Since the
charging process is preferably carried out via a radio
link without the use of wires, there is no need to
expose a cable that has been buried in the ground. If,
nevertheless, a non-rechargeable battery is used to
supply power, then the battery should be used only for
transmission, in order to ensure a long life.
The method for manufacturing a cable includes a step of
providing a transmission element which has at least one
optical waveguide, as well as a step of providing a
plurality of transponder arrangements, each having a
memory for storage of digital data. The transmission
element and the plurality of transponder arrangements
are supplied to a manufacturing unit. A braiding is
produced in the manufacturing unit, by means of which
the transponder arrangements are held on the
transmission element. A cable sheath is extruded around
the braiding, with the transponder arrangements being
very largely protected by the braiding against high
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temperatures which occur during extrusion of the cable
sheath.
For example, a plurality of transponder arrangements
can be supplied to a sheath extruder at regular
intervals during the production of the cable. The cable
sheath is then extruded around the plurality of
transponder arrangements in the sheath extruder, with a
temperature of about 85 C being reached in the sheath
material. Since a normal transponder arrangement may be
subject to a temperature of up to 200 C, the plurality
of transponder arrangements can also be pressed into
the sheath material, while it is still hot.
Normal braiding includes, for example, strain-relief
elements or expanding felts. Many of the normal
substances are also suitable for thermal insulation of
the transponder arrangements against the temperatures
which occur in the sheath material immediately after
sheath extrusion.
The step of producing the braiding preferably comprises
a step of supplying Kevlar fibers or glass fibers.
Kevlar or glass fibers are normally also used for
strain relief.
The method preferably includes a step of provision of a
writer for wire-free transmission of the digital data
to in each case one of the plurality of transponder
arrangements, and a step of writing of the digital data
to the memory of the respective one of the plurality of
transponder arrangements.
The transponder arrangements can be programmed before
or after being introduced into the cable. After being
introduced into the cable, one of the plurality of
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transponder arrangements can then be programmed only
via the transponder, so that it must be possible for
the processor to write to the memory. Before
introduction into the cable and in particular before
sealing of the transponder arrangement, it would also
be possible to program the memory with the transponder
or processor being bypassed. It would then be possible
to configure the memory such that it can be read only
for the processor.
The method preferably includes a step of supplying the
plurality of transponder arrangements with the aid of
an elongated support element in the form of a strip,
which is subdivided in the longitudinal direction into
a plurality of sections in or to which in each case one
of the plurality of transponder arrangements is
respectively mounted or attached.
By way of example, the support element could have a
round cross section and could be introduced into the
cable by means of a supply apparatus which is intended
for transmission elements or strain-relief elements.
The method preferably includes a step of twisting of
the support element with the transmission element.
Such twisting is, for example, worthwhile when the
mechanical characteristics of the support element and
of the transmission element are similar to one another.
However, a plurality of transmission elements can also
be twisted around the support element.
The method for location of a cable includes a step of
providing the cable according to the invention, a step
of storing digital data, from which the length of a
length section of the cable can be determined, in the
memory of the transponder arrangement, and a step of
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providing an instrument for production of a first
measurement signal which propagates along the cable,
for detecting a second measurement signal which arrives
via the cable, and for determining a delay time between
the first and the second measurement signal, on the
assumption that the second measurement signal is
produced by the reflection of the first measurement
signal at the point located along the cable. The
distance between the instrument and that point is
determined from the delay time.
Furthermore, the method includes a step of providing a
reader having a spatially restricted response range
which is dependent on the position of the reader, in
which case the digital data can be read by the reader
from the transponder arrangement when the transponder
arrangement is arranged within the response range, and
a step of reading of the digital data from the memory
and a step of determining the length of the length
section of the cable, and associating the length with
the position of the reader.
The position of that point can be determined by
comparison of the distance determined from the delay
time and the length read from the memory of the
transponder arrangement.
The length of a section of cable laid between two
points can be determined by reading the digital data.
The distance between the two points can be estimated
from the position of the reader and the dimensions of
the response range. This allows the position
coordinates for example of a meter marking on a cable
which has been laid in the ground to be estimated
relatively accurately.
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The length of the cable, measured from the measurement
position, to a line discontinuity can be determined by
measurement of the delay time of an electromagnetic
signal which has been reflected at that line
discontinuity. The route of the cable is then followed
and the length-dependent information is read from in
each case one of the plurality of transponder
arrangements. When a point is reached which corresponds
to the length determined from the measurement of the
delay time, the adjacent transponder arrangements are
located with the greatest possible accuracy by
narrowing the response range, and the location of the
line discontinuity is fixed by suitable interpolation.
The cable can then be exposed, and the line
discontinuity rectified.
The method preferably includes a step of reducing the
response range for more accurate bounding of the
location of the transponder arrangement.
A response range may, for example, initially have a
radius of about 30 m, and is then reduced in steps to,
for example, about 1 m in order to precisely locate one
of the plurality of transponder arrangements.
Brief Description of the Figures
Figure 1 illustrates, by way of example, the
interchange of signals between a cable according to the
present invention and a communication appliance.
Figure 2 shows one exemplary embodiment of a cable
according to the present invention.
Figure 3 shows a cross section through one exemplary
embodiment of a cable according to the present
invention.
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Figure 4 shows one exemplary embodiment of a method for
production of a cable according to the present
invention.
Figure 5 illustrates, by way of example, a method for
location of a cable, and the use of the method for
finding a line defect.
Figure 6 shows the circuit of the transponder
arrangement for a cable according to the present
invention.
Figure 7 illustrates, by way of example, the
electromagnetic coupling between a communication
appliance and the transponder arrangement for a cable
according to the present invention.
Explanation of Exemplary Embodiments of the Invention
Figure 1 shows an example of an arrangement having a
cable according to the present invention and having a
communication appliance 20. The cable 40 has a
plurality of transponder arrangements 10, which are
arranged at a distance from one another along the cable
40 and are integrated in the cable 40. The transponder
arrangements 10 are each designed to store digital data
1231, to receive a first signal 51 and to produce a
second signal 52. A section of the cable 40 is arranged
between each of the adjacent transponder arrangements
10. The communication appliance 20 is designed to
produce the first signal and to detect the second
signal 52. The first signal 51 is used for transmission
of electrical power 511 and of a clock control signal
512 from the communication appliance 20 to the
transponder arrangement 10. The second signal 52 is
used for transmission of the digital data 1231 from the
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transponder arrangement 10 to the communication
appliance 20. The first signal 51 can also be used for
transmission of the digital data 1231, or for
transmission of further digital data 1232. The
transponder arrangements 10 are each designed to store
the digital data 1231 transmitted with the first
signal.
Figure 2 shows one exemplary embodiment of a cable
according to the present invention. The cable 40
contains a plurality of transmission elements 400,
which are surrounded by a cable sheath 41 and extend in
the longitudinal direction of the cable. The
transmission elements 400 each have at least one
optical waveguide and/or metal wire which extends in
the longitudinal direction of the cable. The
illustrated section of the cable also contains one of
the transponder arrangements 10. One of the transponder
arrangements 10 in each case has an antenna 11, an
integrated circuit 12 and connecting contacts 13, with
the integrated circuit 12 being connected to the
antenna 11 via in each case one of the connecting
contacts 13. The integrated circuit 12 is designed to
receive the first signal 51 via the antenna 11, to
transmit the second signal 52 via the antenna 11, and
to store digital data 1231 transmitted with the first
signal 51. By way of example, the digital data 1231 may
include information about the length d of that length
section of the cable 40 which is arranged between the
reference position 0 and in each case one of the
transponder arrangements 10.
Figure 3 shows a cross section through a cable
according to the present invention. The cable 40
contains a cable sheath 41 and, in general, a plurality
of transmission elements 400 which are surrounded by
the cable sheath 41. One of the transmission elements
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400 contains a sleeve 401 and in general a plurality of
conductors 4000, for example optical waveguides and/or
electrical conductors, which each contain a centrally
arranged line area 4002, for example a glass fiber or a
metal wire, and an insulation area 4001 which surrounds
the line area 4002, for example a plastic layer. The
cable 40 may contain a braiding 43, which surrounds the
transmission elements 400. The braiding may contain
holding elements 431 in the form of threads, for
example carbon fibers or glass fibers. The holding
elements in the form of a threads may also be used for
strain relief. The cable has a plurality of transponder
arrangements 10, which are attached to a support
element 60 which extends in the longitudinal direction
of the cable 40. The support element 601 is preferably
a film composed of plastic, to which the transponder
arrangements 10 are attached or in which the
transponder arrangements 10 are mounted. The support
element 60 and the transponder arrangements 10 are, for
example, arranged between the transmission elements 400
and the holding elements 431 in the form of threads.
The support element 60 and the transponder arrangements
can also be arranged between the braiding 43 and the
cable sheath 41. The transponder arrangements 10 may
also be embedded individually in the cable sheath 41.
Figure 4 shows one exemplary embodiment of a method for
manufacturing a cable according to the present
invention. A production line for manufacturing the
cable 40 has a plurality of sleeve extruders 81, a
twisting and braiding apparatus 82, a sheath extruder
83 and a cooling section 84. An appropriate sleeve 401
is extruded, in each case one of the sleeve extruders
81, generally around a plurality of corresponding
conductors 4000, for example optical waveguides or
electrical conductors, thus in each case producing one
of the transmission elements 400. The sleeve extruders
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81 are for this purpose each supplied with the
appropriate conductors 4000 and a melt of a sleeving
material 811. In the twisting and braiding apparatus
82, the transmission elements 400 are first of all
twisted with one another and are then provided with a
braiding 43, in order in this way to form a cable core
42. The twisting and braiding apparatus 82 is for this
purpose supplied with the transmission elements 400 and
the holding elements 431 in the form of threads. The
holding elements 431 in the form of threads can also be
extruded from a melt of a braiding material. The cable
sheath 41 is extruded around the cable core 42 in a
sheath extruder 83, in order in this way to form the
cable 40. For this purpose, the sheath extruder 83 is
supplied with the cable core 42 and a melt of a liquid
sheath material 831. The cable 40 is cooled down along
a cooling section 84, and is wound up onto a cable
drum.
The production line also has a supply unit 85 for
introduction of the transponder arrangements 10 into
the cable 40. By way of example, the transponder
arrangements 10 are fitted by means of a mounting
apparatus 85 to or in an elongated support element 60
in the form of a strip, and are introduced into the
cable sheath 41. By way of example, the support element
60 is supplied together with the transmission elements
400 to the twisting and braiding apparatus 82. This
results in the braiding 43 surrounding the support
element 60 and the transponder arrangements 10.
The support element 60 can also be supplied to the
sheath extruder 83 together with the cable core 42.
This results in the transponder arrangements 10 being
arranged between the cable core 42 and the cable sheath
41.
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The production line also has a writer 201 for
programming of the transponder arrangement 10. The
transponder arrangements 10 can be programmed before or
after introduction into the cable 40. In this case, the
digital data 1231 and in particular information about
the length d of that section of the cable 40 which is
arranged between the respective one of the transponder
arrangements 10 and a reference position 70 are stored
in the memory 123 of in each case one of the
transponder arrangements 10.
Figure 5 shows one exemplary embodiment of a method for
location of a cable 40 and for finding a line defect. A
plurality of transponder arrangements 10 are arranged
in the cable 40. A longitudinal section of the cable 40
with an appropriate length d is arranged between in
each case one of the transponder arrangements 10 and a
measurement position 70. Length sections of the cable
40 with lengths of dl and d2 are in each case arranged
between a first and a second of the transponder
arrangements 10 and the reference position 70. One of
the lengths dl and d2 is in each case stored in in each
case one of the first and of the second of the
transponder arrangements 10. A line defect 71 has
occurred between the first and the second of the
transponder arrangements 10. The cable 40 is accessible
at the reference position 70. In order to find the line
defect 71, a signal is first of all produced with the
aid of a measurement apparatus 90, which is connected
to one of the conductors 4000 at the reference position
70, and this signal propagates along the cable 40. A
portion of the signal is reflected at the line defect
71, and is detected by the measurement apparatus 90.
The length Ls of that section of the cable 70 which is
arranged between the reference position 70 and the line
defect is determined from the delay time Ot of the
reflected portion of the signal. The first and the
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second of the transponder arrangements 10, between
which the line defect has occurred, are then located.
For this purpose, the reader 20 is moved along the
approximate route of the cable 40, starting from the
reference position 70, in the direction of the line
defect 71. During this process, the reader 20 emits a
first signal 51. One of the transponder arrangements 10
which is in each case located in the response range
2011 around the reader 20 receives electrical power and
a system clock via the first signal 51, and transmits
the digital data 1231 stored in it via the second
signal 52. This in each case results in the reader 20
reading the digital data 1231 from those transponder
arrangements 10 which are within the response range
2011. If no data is read, then none of the transponder
arrangements 10 are within the response range 2011. If
at least one of the transponder arrangements 10 is
within the response range 2011, then the length d of
that length section of the cable 40 which is arranged
between the at least one of the transponder
arrangements 10 and the reference position 70 can be
determined. At the same time, the position 2010 and the
response range 2012 of the reader are known. If, in
particular, the digital data 1231 from the first and
the second of the transponder arrangements 10 is read
by the reader 20 with the respectively stored value for
the lengths dl and d2, then the line defect 71 which is
arranged between the first and the second of the
transponder arrangements 10 is located within the
response range of the reader 20, and is thus located.
The accuracy of the described location process can be
improved by reducing the radius and/or the spatial
angle of the response range 2011, by decreasing the
transmission power and/or by using a directional
antenna.
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Figure 6 shows the circuit of the transponder
arrangement 10 for a cable 40 according to the present
invention. The circuit has a transmitter 124 and a
receiver 125, which are each connected to the antenna
11, a processor 122 which is connected to the
transmitter 124 and to the receiver 125, and a memory
123 which is connected to the processor 122. The
circuit also has a rectifier 120, which is connected to
the antenna 11, in order to supply the processor 122,
the transmitter 124 and the receiver 125 with a DC
voltage, and has a clock control 121, which is
connected to the antenna 11, for supplying the
processor 122 with a system clock C. A rechargeable
battery 126 is provided in order to supply a voltage V
to the rectifier 120. The rechargeable battery 126 can
in this case preferably be recharged without the use of
wires. This means that the transponder arrangement is
available at any time, after a short charging phase.
The use of a radio link to charge the rechargeable
battery avoids the need to dig up and expose the cable
and the transponder device. Instead of this, the
rechargeable battery can be charged by a user through
the surface of the earth.
It is, of course, also possible to use a purely passive
system. In this case, the rechargeable battery 126 in
figure 6 is not provided. In order to supply power
passively to the transponder arrangement, power is
taken from the electrical field which is emitted from
the reader to the antenna 11, and is used to operate
the transponder arrangement.
The receiver 125 receives digital input data I from the
first signal 51, which is received via the antenna 11,
and transmits this to the processor 122. The
transmitter 124 inserts digital output data 0, which
has been transmitted from the processor 122, into the
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second signal 52. The input data I is used by the
processor 122 for control purposes, or is stored in the
memory 123. The output data 0 is read by the processor
122 from the memory 123.
Figure 7 shows the electromagnetic coupling between the
reader 20 and one exemplary embodiment of the circuit
of the transponder arrangement 10 according to the
present invention. The antenna 11 of the transponder
arrangement 10 and the further antenna 21 of the reader
20 are each in the form of coils, which are inductively
coupled. The inductance of the antenna 11 and the input
capacitance 1251 form a parallel resonant circuit,
which is damped by the winding resistance 111 of the
antenna 11 and by the load resistance 1252, and whose
resonant frequency is tuned to the transmission
frequency of the reader 20.
A radio-frequency magnetic alternating field is
produced in the further antenna 21 of the reader 20 in
order to read the digital data 1231 which is stored in
the transponder arrangement 10. This results in a
radio-frequncy AC voltage being induced in the antenna
11 of the transponder arrangement 10. A DC voltage and
a clock frequency for the power supply and clock
control for the processor 122 are derived from the
radio-frequncy AC voltage.
A switch S is controlled by the output data 0 that is
transmitted from the processor 122 of the transponder
arrangement 10 to the transmitter 124. For example, a
high level corresponds to a closed state, and a low
level corresponds to an open state of the switch S.
When the switch S is closed, the further load
resistance 1253 is connected in parallel with the load
resistance 1252. The total load resistance on the
parallel resonant circuit is thus changed as a function
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of the state of the switch S. If the load resistance is
relatively low, a greater current flows in the antenna
11. A change in the total load resistance results in a
change in the current in the antenna 11 and, as a
consequence of the inductive coupling, also in an
additional voltage in the further antenna 21 of the
reader 20. The output data 0 can thus be transmitted
from the transponder arrangement 10 to the reader 20 by
means of this so-called transformer coupling.
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List of Reference Symbols
Transponder arrangement
11 Antenna
111 Antenna resistance
12 Integrated circuit
1251 Input capacitance, capacitor
1252 Input resistance
1253 Load resistance
1254 Controllable switch
120 Rectifier
121 Clock control
122 Processor
123 Memory
124 Transmitter
125 Receiver
13 Connecting contacts
Communication appliance
2010 Location of the communication appliance
2011 Response range
R Radius
8 Spatial angle
Further processor with control program
Cable
41 Cable sheath
42 Cable core
43 Braiding
400 Transmission element
401 Sleeve
4000 Optical waveguide or electrical conductor
4001 Fiber coating or wire insulation
4002 Glass fiber or metal wire
51 First signal
52 Second signal
511, P Electrical power
512, C System clock
1231 Digital data
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12311 First feature
1232 Further digital data
12321 Second feature
60 Support element
70 Reference position
71 Line defect
81 Sleeve extruder
811 Sleeve material
82 Twisting and braiding apparatus
83 Sheath extruder
831 Sheath material
84 Cooling path
85 Mounting apparatus
90 Instrument for measurement of a delay time
