Method and locating system for identifying a marker

Abstract

The present disclosure relates to a method and a locating system for identifying a marker, in particular in a locating environment of a locating device. The method comprises several method steps. In a first step, a pulsed alternating magnetic field is generated by the locating device in order to excite a marker resonant circuit of the marker, in particular an L-C resonant circuit. Furthermore, electrical energy is obtained from the excited marker resonant circuit in order to supply an electronic circuit in the marker. In addition, the dying-away of the marker resonant circuit is modulated with a marker-specific identifier. Subsequently, a modulated output signal having the marker-specific identifier is transmitted from the marker to the locating device, and the marker is identified by extracting the marker-specific identifier in the locating device by demodulating the transmitted output signal.

Description

[0001] P609788PC00

[0002] Method and location system for identifying a marker

[0003] DESCRIPTION

[0004] The present disclosure relates to methods for identifying a marker in a tracking environment of a tracking device and / or a tracking system for identifying a marker in a tracking environment of a tracking device. Furthermore, the present disclosure relates to a tracking device and an identifiable marker.

[0005] State of the art

[0006] Tracking systems typically consist of an active locator (tracking device) and a passive marker. The locator generates a pulsed alternating magnetic field tuned to the marker's resonant frequency range. The marker contains an LC resonant circuit with a typical resonant frequency of approximately 100 kHz, depending on the application (e.g., telecommunications, gas).

[0007] When the locator approaches a marker and excites the magnetic field, the marker resonates. When the locator switches off the field, the marker emits an electromagnetic field due to the decay of the resonant circuit, which is received by the locator. The intensity of the received signal decreases proportionally to the cube of the distance. This mechanism enables the localization of a marker. However, systems known in the prior art have several disadvantages.

[0008] One of the key problems is that all prior art markers are based on the principle of the separately excited resonant circuit and are therefore not individually identifiable. In practice, this means that while the locator can detect that a marker is nearby, it cannot distinguish between multiple markers. This limitation is particularly problematic in applications such as locating specific objects, e.g., a fiber optic cable.

[0009] This presents an obstacle, as additional technologies or procedures are required for unambiguous identification.

[0010] Against the background of this prior art, the purpose of the present disclosure is to specify methods and a locating system, as well as a locating device and an identifiable marker, each of which is suitable to enrich the prior art.

[0011] The problem is solved by the features of the independent claims. The dependent and subordinate claims each contain optional further developments of the disclosure.

[0012] The task is then solved, according to a first aspect, by a method for identifying a marker in a localization environment of a localization device.

[0013] For the purposes of this disclosure, identification refers to a technical process in which a marker is recognized in a tracking environment by the unambiguous recognition of its specific identifier. The marker is a passive element containing a marker resonant circuit and is excited by an external alternating magnetic field. It can receive and re-emit electromagnetic signals. The process is based on the analysis of a modulated output signal emitted by the marker. The output signal is generated by modulating the oscillation of the marker resonant circuit and contains the identifier relevant for identification. For this purpose, the tracking device receives the modulated signal and processes it further. The frequency and / or phase information of the signal is evaluated to extract the identifier.The tracking device uses a demodulation technique, such as frequency-shift keying (FSK), for example a frequency discriminator, to read the encoded data contained in the signal. The extracted specific identifier serves as a unique identifier for the marker, thus preventing confusion with other markers. P609788PC00.

[0014] For the purposes of this disclosure, the tracking device is an active device capable of generating an alternating magnetic field and receiving and demodulating modulated signals from markers. The tracking environment of the tracking device refers to the spatial and physical area in which the tracking device and the marker interact. It encompasses all environmental factors that can influence both the generation and propagation of the alternating magnetic field and the transmission and reception of the modulated output signal. Within the tracking environment, the tracking device generates a pulsed alternating magnetic field that can induce resonance in the marker's resonant circuit. Spatial proximity between the marker and the tracking device is crucial, as the field strength of the alternating magnetic field decreases with increasing distance.This decrease in signal strength is proportional to the cube of the distance, meaning that the detection range is limited to a few meters. Within this range, the signal strength must be sufficiently high to reliably activate the marker.

[0015] The method can comprise several steps. In a first step, a pulsed alternating magnetic field is generated by the locating device to excite a marker resonant circuit. An LC resonant circuit can be used as the marker resonant circuit and is excited by the locating device. The LC resonant circuit represents a specific type of marker resonant circuit, consisting of an inductor L and a capacitor C, which together are used to determine the resonant frequency.

[0016] Pulsed operation of the magnetic field of the tracking device enables efficient marker excitation while simultaneously reducing the device's energy consumption. The marker's resonant circuit is brought into resonance, generating a stable electromagnetic field that forms the basis for subsequent process steps. The resonant circuit's resonance can be frequency-specific and tuned to typical values ​​of approximately 100 kHz, depending on the application. This allows for a precise and application-specific excitation process. P609788PC00

[0017] In a further process step, electrical energy is extracted from the excited marker resonant circuit to power an electronic circuit within the marker. Extracting electrical energy involves converting the energy stored in the marker resonant circuit into an electrical supply voltage that can be used for control and / or modulation within the marker. Specifically, the electronic circuit and its electronic components can be powered. Rectifying the voltage in the resonant circuit yields the necessary electrical energy, designed to support the subsequent functions of the marker. The use of energy-efficient technologies such as CMOS circuits reduces energy consumption to a minimum, ensuring reliable operation of the electronic circuit even at low voltage levels.This ensures the marker's self-sufficiency.

[0018] In a further step, the decay of the marker resonant circuit is modulated with a marker-specific identifier. This modulation is achieved by adjusting the resonant circuit's capacitance to encode frequency changes. This enables data transmission without significant energy loss. The specific identifier can be encoded using a shift register that provides bits sequentially. The technical benefit lies in the precise and energy-efficient data transmission, which allows for the unique identification of the marker. For the purposes of this disclosure, the marker-specific identifier represents a unique code used to identify a marker. This identifier can be a serial number or another format-dependent pattern.

[0019] One possible implementation of the marker-specific identifier is through modulation of the marker's resonant circuit's decay. Here, the marker-specific identifier is provided as a digital sequence of bits and integrated into the output signal. The data required for encoding is generated by a chained shift register, which sequentially outputs bits that control the modulation in real time. This modulation is preferably achieved using frequency shift keying (FSL).

[0020] (FSK) is implemented, in which a logical "0" is encoded by shifting the resonant frequency and a logical "1" by maintaining the resonance. The frequency change is controlled by switching on or off resonant circuit capacitances, which ensures continuous oscillation of the marker resonant circuit.

[0021] Programming the specific identifier can be performed during the marker's manufacturing process. The serial number can be implemented using closed or open programming bridges at the shift register inputs. In one embodiment, these bridges are closed by default after manufacturing and are selectively opened with a laser to define the desired bit pattern for the serial number. This method represents a robust and cost-effective approach, as no complex electronic control is required at runtime.

[0022] This enables the use of a passive marker powered by the energy of the excited resonant circuit, allowing for completely autonomous operation without an external power source. This reduces maintenance costs and extends the marker's lifespan. Furthermore, the continuous oscillation of the resonant circuit ensures stable energy transmission and signal strength despite modulation, improving communication range and reliability. Frequency modulation minimizes energy loss, as the oscillation system itself experiences only minimal damping.

[0023] Subsequently, a modulated output signal containing the marker's specific identifier is transmitted from the marker to the tracking device. This modulated output signal is an electromagnetic signal generated by modulating the oscillation of the marker's resonant circuit and includes the marker's specific identifier. Specifically, the modulated signal is generated by the oscillations of the excited resonant circuit and transmitted to the tracking device. The continuous oscillation in the marker ensures stable signal transmission, minimizing interference from multiple signal repetitions.

[0024] This approach can provide reliable communication between the marker and the tracking device.

[0025] In a further process step, the marker is identified by extracting its marker-specific identifier within the tracking device through demodulation of the transmitted output signal. Demodulation is the process within the tracking device in which the received modulated output signal is analyzed and / or evaluated to extract the specific identifier it contains. The tracking device receives the modulated signal (output signal) and analyzes it, for example, using FSK demodulation. The marker-specific identifier is then extracted and used for identification. Synchronization can be achieved using a monostable multivibrator (monoflop), which controls the identifier blocks, thus enabling error-free signal processing. This allows for robust and reliable marker identification even under challenging environmental conditions.

[0026] The previously described method and the tracking system described below offer several advantages. Exciting the marker's resonant circuit with a pulsed alternating magnetic field allows for effective and targeted activation of the marker, resulting in high energy efficiency. Energy harvested from the excited resonant circuit means the marker operates without external power sources, making it low-maintenance and sustainable. Modulating the decay signal with a specific identifier ensures unambiguous identification, preventing confusion between multiple markers. This increases the reliability and precision of the tracking system, especially in complex environments with multiple markers. The modulated output signal enables robust data transmission that remains stable even under external influences such as interference or weak coupling.Furthermore, the demodulation and extraction of the specific identifier in the tracking device ensures consistent and error-free data processing, enabling the tracking system and consequently the method to reliably and unambiguously identify the marker even under difficult conditions. P609788PC00.

[0027] The method for identifying a marker may be a computer-implemented method, meaning that one, several, or all steps of the method may be at least partially performed by a computer or data processing device. Where practical and / or technically feasible, the steps may be performed in a different order than described and / or claimed above.

[0028] Possible further developments of the aspect of disclosure described above are explained in detail below. Each of the further developments mentioned below can, separately and in combination, further develop and specify the procedure described above.

[0029] It can be implemented that the modulation is achieved by controlling resonant circuit capacitors via a switch. The marker resonant circuit is modulated by switching these capacitors on or off. These capacitors are part of the marker resonant circuit and influence its resonant frequency. Modulation is achieved by adjusting this resonant frequency, particularly in the form of frequency-shift keying (FSK), where different frequencies are used to represent digital states such as "0" and "1". The resonant circuit capacitors can be arranged in parallel with the main capacitor of the resonant circuit to allow for targeted changes in the overall capacitance. This configuration ensures that the oscillation remains continuous and that no significant damping of the system occurs, thereby minimizing energy losses.

[0030] The switch used can be of various designs. It can be an electronic switch, such as a transistor. This switch is controlled by the marker's electronic circuitry and allows for the targeted activation or deactivation of the additional capacitances. The electronic switch is energy-efficient and, due to its low power consumption, is suitable for operation in a passive marker powered by the energy of the excited resonant circuit. Alternatively, mechanical switches (P609788PC00) can also be used.

[0031] It should be provided for, with electronic switches being preferred due to their fast switching times and precise controllability.

[0032] The modulation method ensures reliable transmission of the marker's specific characteristic and can improve signal quality by maintaining a low-loss and stable oscillation in the marker's resonant circuit. This can contribute to greater range and improved interference immunity.

[0033] Furthermore, it may be provided that at least one of the following modulation methods is used for modulation: FSK, ASK, PSK, or CPM. The disclosed method can be implemented using various modulation methods that enable both precise and energy-efficient data transmission. Frequency-shift keying (FSK) is preferred because it maintains a constant oscillation amplitude in the marker resonant circuit, thus avoiding energy losses. Alternatively, amplitude-shift keying (ASK), phase-shift keying (PSK), or continuous phase modulation (CPM) can also be used, depending on the application requirements. Each of these methods offers different advantages with regard to data rate, noise immunity, and energy efficiency, and the choice of modulation method can depend on the environment and the technical conditions.

[0034] The marker-specific identifier can include a marker serial number provided by a shift register with programmable bridges. This marker-specific identifier can be represented by a serial number, which can be implemented using various technical methods. The serial number can be a fixed sequence programmed during manufacturing, or alternatively, a flexibly programmable sequence that can be adjusted after production. The serial number can be provided by a shift register that sequentially supplies the individual bits for modulating the resonant circuit.

[0035] The shift register is a digital circuit comprising a series of interconnected memory cells which store data in a defined sequence. P609788PC00

[0036] The register structure can be parallel or serial and allows data to be read either bitwise or block-wise. In the present implementation of the marker, the shift register is chained, meaning it comprises several register units connected in series, which together form the entire serial number. This design ensures that the serial number bits are provided precisely and sequentially for modulating the output signal.

[0037] The serial number can be programmed using programmable bridges that act as switching points between the inputs of the shift register. These bridges can be electrically conductive or open and serve to define the desired bit pattern. During manufacturing, all these bridges can initially be closed. A laser can be used to selectively cut individual bridges, thereby creating a permanent switching state.

[0038] Alternatively, electrically programmable bridges can be used, which can be switched to conductive or non-conductive states by an external controller. This allows for subsequent adjustment of the serial number, which can be particularly advantageous for markers intended for use in different application scenarios.

[0039] An alternative design involves using ROM (Read-Only Memory) to store the serial number. In this case, the number is test-coded in non-volatile memory during manufacturing. Another design uses EEPROM (Electrically Erasable Programmable Read-Only Memory), which allows the serial number to be changed electrically after production. These memory options offer flexibility in marker configuration and can facilitate adaptation to specific requirements.

[0040] This allows for a combination of stability, flexibility, and reliability. Laser-programmable bridges offer a robust and tamper-proof method for setting the serial number, which remains stable even under harsh environmental conditions. Electrically programmable bridges and EEPROM modules, on the other hand, allow for dynamic adjustment, which is why the P609788PC00

[0041] Inventory management is simplified and the application range of the markers is expanded. Sequential output of the bits from the shift register enables precise control of the resonant circuit's modulation, thus ensuring error-free data transmission. This modular and adaptable architecture is particularly advantageous in complex technical environments where unambiguous and reliable marker identification is required.

[0042] The electronic circuitry can be implemented using CMOS technology. The marker's electronic circuitry is based on CMOS technology, which is characterized by high energy efficiency and low power consumption. CMOS circuits can operate at supply voltages below 2 volts and require only very low currents in the microampere range. This allows the marker to operate autonomously using the energy generated in the resonant circuit and extends the lifespan of the tracking system, as no external power supply is required.

[0043] It can be provided that the output signal is transmitted synchronously. Synchronized transmission of the output signal means that the data, in particular the marker-specific identifier, is sent in a precisely defined temporal sequence. Synchronization ensures that all bits of the specific identifier are transmitted to the tracking device in a consistent sequence and at regular intervals. Furthermore, synchronization ensures that the marker and the tracking device recognize the same bit as the beginning of a multi-bit identifier. This ensures that the tracking device can correctly detect and interpret the signal, even in the presence of external interference such as electromagnetic disturbances or fluctuating signal strengths.Without synchronization, data misinterpretation could occur, as bits might be incorrectly assigned or detected with a time delay. Furthermore, implementing a fixed transmission interval improves coupling between the marker and the tracking device, thereby increasing the overall reliability of the tracking system. P609788PC00

[0044] Synchronized transmission can utilize various data structuring methods, including block transmissions, where the specific identifier is sent in clearly defined data packets. Synchronized pauses or control bits can be inserted between these blocks to allow the tracking device to precisely time the received data. This reduces the risk of individual bits being misinterpreted due to signal loss and improves data integrity.

[0045] The transmission synchronization can be achieved using a monostable multivibrator (monostable flip-flop), which controls the cycle of transmitting a complete marker-specific identifier. A monostable multivibrator generates a defined electrical signal for a specified time period after an external trigger. In the context of the invention, the monostable multivibrator serves as a precise timer that controls the synchronization of the output signal transmission. This circuit ensures that the entire cycle for transmitting the marker-specific identifier is precisely defined and that no timing deviations occur.

[0046] The monostable multivibrator (monofloop) is activated as soon as the license plate transmission begins and controls the bit sequence as well as the pauses between individual data blocks. This functionality ensures that the tracking device can reliably detect the start, duration, and end of each transmission cycle.

[0047] Furthermore, precise timing can reduce the likelihood of synchronization errors, especially when processing multiple consecutive data packets. This is advantageous for ensuring correct and continuous data transmission even in noisy environments.

[0048] Another advantage of the monostable multivibrator (monostable multivibrator) is its high stability and low sensitivity to external influences, since the time constant is determined by internal electronic parameters (such as capacitances and resistances). This stability enables reliable long-term control of the transmission and minimizes deviations in the transmission rate. P609788PC00

[0049] The marker's resonant circuit may include an antenna, specifically a ferrite antenna. This ferrite antenna is optimized for excitation and transmission of electromagnetic signals due to its high Q factor and pronounced directivity. Ferrite antennas are particularly compact and, due to their small size, are well-suited for use in passive markers. Their resonance-specific properties contribute to precise signal transmission and stable coupling with the locating device.

[0050] It may be provided that the transmitted output signal is transmitted and / or evaluated at least twice in succession and the marker-specific identifier is extracted in order to detect and compensate for transmission errors caused by interference.

[0051] Multiple transmissions of the output signal enable robust and reliable data transmission. Transmitting the signal at least twice in succession allows for the detection of transmission errors that can arise from brief disturbances or fluctuating signal strengths. A single signal can be corrupted in an interference-prone environment by external influences such as electromagnetic interference and / or obstacles. However, if the signal is transmitted repeatedly, there is a significantly higher probability that at least one of the transmissions will be received without errors. This increases the likelihood of correct data acquisition.

[0052] Evaluating the signal two or more times offers additional advantages in error detection and compensation. By comparing the multiple received signals, the locating device can detect inconsistencies and thus identify faulty data. For example, if a bit in one of the signals has been corrupted by noise, evaluating another signal in which the corresponding bit was transmitted correctly can enable reliable error correction. This approach can reduce reliance on a single P609788PC00

[0053] Reduces signal transmission and improves data integrity, especially in noisy environments.

[0054] Extracting the marker-specific identifier is a crucial component of accurate marker identification. This approach involves demodulating and analyzing the transmitted signal to read the bit sequence representing the specific identifier. Repeated transmission and evaluation ensure the accuracy of the extracted sequence, even if individual bits are corrupted during transmission. This redundancy allows the tracking device to detect and compensate for even the smallest errors in the data stream by comparing the results of multiple transmissions. This minimizes the probability of misidentification and significantly increases the overall system reliability.

[0055] Furthermore, according to another aspect of the disclosure, the task is solved by the tracking system. The tracking system is designed to identify the marker within the tracking environment of a tracking device. The tracking system includes the tracking device. Furthermore, the tracking system includes the marker to be identified.

[0056] The tracking device is an active device used to uniquely identify a marker in a tracking environment. It is equipped with several functional means that perform specific tasks within the tracking process.

[0057] The means for generating a pulsed alternating magnetic field can be formed by an excitation unit comprising a coil or a combination of several coils. These coils are connected to an electronic circuit that generates periodic electrical pulses, which build up the magnetic field. The frequency of the alternating magnetic field can be tuned to the resonant frequency of the Marker resonant circuit, preferably in the range of approximately 100 kHz. An alternative implementation could be achieved using a P609788PC00

[0058] Inductively coupled multi-frequency sources are used, which make it possible to excite several markers with different resonant frequencies in parallel.

[0059] The means for receiving a modulated output signal can consist of one or more receiving antennas. In one embodiment, a configuration comprising three orthogonally arranged antennas can be used to improve the signal strength's independence from orientation. The received signals can be further processed by amplifiers and filters to improve signal quality and suppress interference. In an extended embodiment, digital signal processors (DSPs) can be used to perform noise reduction and signal extraction in real time.

[0060] The means for demodulating the received output signal are designed to extract the marker's specific characteristic from the received signal. These means can be implemented using digital demodulation circuits that analyze frequency or amplitude changes, depending on the modulation technique used (e.g., FSK or ASK). A microcontroller or a specialized demodulator chip can be used to control and evaluate the entire process. The demodulation is synchronized, ensuring that the marker's data packets are correctly assigned and processed.

[0061] The marker is a passive element designed to enable unique identification within the detection environment of the tracking device. The marker comprises various functional units that are interconnected to ensure the modulation and transmission of the output signal.

[0062] The Marker resonant circuit, particularly in its LC configuration, consists of at least one inductor and at least one capacitor, which together define a resonant frequency. The inductor can be implemented as a ferrite antenna, which, due to its high Q factor and directivity, provides efficient excitation and oscillation. The resonant circuit's capacitances can be provided by fixed capacitors and / or switchable resonant circuit capacitors, which are used for modulating the decay. P609788PC00

[0063] The electronic circuitry within the marker is designed to utilize the electrical energy generated by its oscillation behavior to modulate a specific identifier in the output signal. This circuitry can be implemented as a CMOS circuit, which offers high energy efficiency and operates at low voltages and currents. A cascaded shift register provides the bit sequence of the specific identifier sequentially, while a switch controls the modulation by enabling or disabling capacitors.

[0064] The means for transmitting the output signal consist of the antenna of the resonant circuit, which radiates the modulated signal. The continuous oscillation of the circuit ensures that the signal can be transmitted stably and with minimal loss. Alternatively, additional amplifiers can be incorporated to increase the signal's range. Redundancy measures, such as repeated signal transmission, minimize transmission errors and increase the reliability of communication between the marker and the tracking device.

[0065] The tracking system offers a variety of technical advantages resulting from the targeted combination of the marker and tracking device, as well as the synchronization and modulation of the signal.

[0066] A significant advantage is that the marker can be operated completely passively and therefore maintenance-free. The energy to power the electronic circuitry is derived from the marker's oscillating circuit, eliminating the need for external power sources such as batteries or cables. This reduces maintenance and operating costs and increases the marker's service life.

[0067] By using a specific identifier stored in the marker, unique identification is enabled. This function is particularly important in complex infrastructure applications where numerous markers may be present and targeted assignment is required. The P609788PC00 can be used with the modulated output signal.

[0068] Markers can be reliably detected by the tracking device, even if external influences such as electromagnetic interference or weak signal strengths occur.

[0069] Synchronized transmission and processing of the output signal ensures error-free data extraction. The transmission cycle is precisely controlled using a monostable multivibrator (monostable multivibrator), guaranteeing the synchronization of data packets. Multiple transmissions and evaluations of the signals enable additional error detection and compensation. This enhances data security and ensures reliable identification even under challenging conditions.

[0070] Another advantage of the tracking system lies in the position-independent nature of the signal transmission. The tracking device can be equipped with multiple, orthogonally arranged antennas, allowing the signal to be received regardless of the marker's orientation in space. This significantly improves the range and reliability of the tracking, especially in situations where markers are difficult to access or awkwardly positioned.

[0071] The locating device may include means for synchronizing the transmission of the output signal with a cycle of a monostable multivibrator of the marker.

[0072] The means for synchronization can consist of an electronic circuit integrated into the tracking device, operating in conjunction with a monostable multivibrator (monoflop) in the marker. A monostable multivibrator generates a precise time interval when activated. This time interval controls the transmission cycles of the output signal. Using a synchronized clock signal, the tracking device can detect when the next data packet is received and adjust its processing accordingly. Alternatively, a digital control unit can be used to generate synchronized pulses.

[0073] Implementing this function can provide precise and interference-resistant data transmission, as synchronization errors are avoided. P609788PC00

[0074] This allows the tracking device to reliably extract the specific marker identifier even under difficult conditions, as the data packets are correctly assigned and processed in the correct order.

[0075] The locating device may be configured to receive and evaluate the modulated output signal at least twice in order to detect and compensate for transmission errors. The locating device can perform multiple reception cycles for the same output signal. The received data packets are analyzed using a comparator circuit or a digital signal processor. In the event of discrepancies between the received packets, erroneous data can be corrected by comparing the redundant transmissions.

[0076] This function contributes to improved reliability by detecting and compensating for transmission errors caused by interference such as electromagnetic fields or signal shielding. This enhances data integrity and ensures that the specific marker identifier is correctly read even with weak signals. Multiple evaluations enable continuous monitoring of signal quality and real-time adjustment of reception conditions.

[0077] The tracking device may include a tracking module that determines the marker's position information and links this information to a database to store the marker's unique identifier and location. The tracking module may be a GPS module or another GNSS (Global Navigation Satellite System) module. This module enables the tracking device to determine its current position at the time of marker identification. The acquired position data, along with the marker's unique identifier, can be stored in a database. This database may be hosted locally on the tracking device and / or in a cloud environment, allowing for centralized management and storage of the information.

[0078] This function allows the tracking system to not only identify markers by their identifier but also to document their geographic position. This is particularly important in infrastructure monitoring applications, such as the laying and maintenance of cables or pipes. Storing the data in a database ensures efficient tracking and retrieval of the marker. Furthermore, access to the position information enables quick orientation and navigation during on-site maintenance work.

[0079] The marker may include a ferrite antenna, which is integrated into the marker's resonant circuit. The ferrite antenna has a core made of magnetically conductive material, increasing the inductance of the resonant circuit and ensuring high Q-factor. The ferrite antenna is capable of efficiently receiving and transmitting electromagnetic oscillations. Due to its compact design, it is particularly well-suited for marker applications where space and energy efficiency are critical factors.

[0080] This feature enables stable coupling between the marker and the tracking device, even in weak alternating magnetic fields. Furthermore, the ferrite antenna reduces energy losses and improves signal quality, which can increase the range and reliability of the tracking system.

[0081] It may be possible to include means for compensating for the influence of the marker's antenna orientation in space on the strength of the received signal. These compensating means can consist of multiple antennas arranged orthogonally to one another. This antenna configuration makes it possible to maximize the signal strength regardless of the marker's orientation in space. Alternatively, electronic signal processing circuits can be used that combine the received signals from multiple antennas and determine the optimal reception conditions.

[0082] This function minimizes the signal's positional dependence. This ensures that the marker is reliably detected even when the antennas of the P609788PC00 are in an unusual orientation.

[0083] The tracking device and the marker are not optimally aligned with each other.

[0084] This significantly improves the functionality of the tracking system in environments with difficult reception conditions.

[0085] The disclosure also includes further developments of the previously described tracking system, which exhibit characteristics already described in connection with the further developments of the disclosed method. For this reason, the corresponding further developments of the disclosed method are not described again here, and what was described above with regard to the method also applies analogously to the tracking system and vice versa.

[0086] One aspect of the present disclosure relates to a further method for identifying a marker in a tracking environment of a tracking device. The method can be executed by the tracking device. The method can be a computer-implemented method, i.e., one, several, or all steps of the method can be executed, at least partially, by a computer or a device of the tracking device configured for data processing. Where practical and / or technically feasible, it may be provided that the steps are executed in a different order than described and / or claimed above. The method can comprise several process steps.

[0087] It can be provided that a pulsed alternating magnetic field is generated by the tracking device. The excitation of the marker resonant circuit is initiated by a series of electrical pulses that generate a magnetic field with periodic interruptions. These pulse signals are designed to be tuned to the resonant frequency of the marker resonant circuit. Alternatively, the pulse generation can also be variable to cover different marker frequencies within a tracking system.

[0088] This allows the marker resonant circuit to be set into oscillation efficiently, thereby optimizing energy transfer. The periodic interruptions also result in better differentiation between the excitation signal and the P609788PC00.

[0089] The marker's response signal enables this. This increases the precision of identification and reduces the risk of interference from continuous fields.

[0090] The tracking device can be configured to receive a modulated output signal from the marker in response to the pulsed alternating magnetic field. The receiving unit of the tracking device is equipped with antennas and signal processing circuitry specifically designed to receive modulated signals with minimal distortion and interference. Multiple receiving antennas can be used to ensure signal quality even when the marker's orientation varies. This enables reliable signal acquisition, even under challenging environmental conditions. As a result, the tracking device can precisely analyze the modulation and identify the marker's unique identifier with minimal signal loss. Furthermore, the parallel use of multiple antennas improves the range and stability of the communication.

[0091] The received output signal may be processed, with demodulation performed to extract the marker-specific identifier for marker identification. The tracking device's processing unit performs digital or analog demodulation, depending on the modulation method used (e.g., FSK or ASK). An integrated microcontroller or a specialized signal processor analyzes the received data, filtering out interference and signal distortion. This function contributes to robust and error-free data extraction. Demodulation enables precise and reliable identification of the marker's specific identifier. This reduces the risk of misidentifications, even with multiple data transmissions or weak signal strength.The combination of optimized signal processing and synchronized data analysis increases the efficiency of the entire identification process.

[0092] Furthermore, it may be provided that the processing of the received output signal includes at least two detection and evaluation steps to identify and compensate for transmission errors. This can improve the reliability and accuracy of P609788PC00

[0093] Data transmission efficiency is increased. By repeatedly detecting and evaluating the received signal, temporary disturbances, such as electromagnetic interference, can be identified. Faulty data bits that occur during a single transmission can be reliably corrected by comparing them with redundant signals. This ensures data integrity even in interference-prone environments. The tracking system becomes more robust against interference and guarantees continuous, error-free marker identification.

[0094] Furthermore, the modulated output signal can be received by a receiver unit designed to reduce the positional dependence of the output signal strength. The receiver unit can include a multi-antenna configuration with antennas arranged orthogonally to each other. This arrangement maximizes the signal strength regardless of the marker's spatial orientation within the detection environment. Alternatively, signal processing circuits can be used to combine incoming signals from multiple reception paths to ensure optimal reception quality. This allows the marker to be reliably detected even with an unfavorable spatial orientation. The receiver unit automatically compensates for fluctuations in signal strength that may be caused by different antenna positions and / or obstacles.This improves the stability of the signal transmission and increases the range of the tracking system, as the reception quality no longer depends solely on the optimal coupling between the antennas.

[0095] Furthermore, the received output signal can be synchronized with a cycle of a monostable multivibrator (monoflop) in the marker to synchronize the processing. Synchronizing the processing with a monostable multivibrator cycle ensures that the data packets of the output signal are received and processed in the correct temporal sequence. The monostable multivibrator generates precise time intervals that control the transmission and reception cycles. The locating device can detect these intervals and adjust the data processing accordingly. Stable and synchronized data transmission can be achieved. Errors caused by timing shifts of the P609788PC00

[0096] Potential data packet errors can be avoided. The tracking device can reliably identify synchronization points in the signal and thus extract the data accurately. This contributes to increased overall system efficiency by eliminating synchronization errors and ensuring continuous data processing.

[0097] One aspect of the present disclosure relates to the tracking device. The tracking device is designed to identify a marker.

[0098] The tracking device may include an excitation unit with means designed to generate a pulsed alternating magnetic field. These means may comprise a coil or a combination of several coils, which are periodically supplied with current pulses by an electronic circuit. Control is achieved by a digital or analog generator that produces precise time intervals and pulse shapes for field generation. An alternative implementation may include a multi-channel control unit covering different frequency bands to excite various markers in a tracking system simultaneously.

[0099] The locating device functions by selectively activating the marker's resonant circuit through resonance excitation. The pulsed field also allows for better separation between the excitation field and the output signal generated by the marker's modulation, resulting in higher detection accuracy.

[0100] The tracking device may include a receiver unit designed to receive a modulated output signal from the marker. The receiver unit may consist of multiple receiving antennas arranged orthogonally to maximize signal reception regardless of the marker's spatial orientation. Amplifier and filter elements may also be integrated to amplify the received signals and suppress unwanted interference. Another implementation option is P609788PC00.

[0101] This consists of the use of digital signal processors (DSPs) that enable real-time signal processing and noise reduction.

[0102] This ensures stable and reliable acquisition of the output signal. The receiver unit's ability to compensate for signal interference and maximize the quality of the received signal can improve the range and precision of the tracking device.

[0103] The tracking device may include a processor unit configured to process the received output signal and extract a marker-specific identifier by demodulation. This unit may consist of a microcontroller or a specialized processor optimized for analyzing and processing modulated signals. The processor may execute the previously disclosed method. The demodulation logic may support various modulation techniques, including frequency-shift keying (FSK), amplitude-shift keying (ASK), or phase-shift keying (PSK). The processor unit performs time-synchronized data extraction, compensating for disturbances and errors through redundant signal processing. This enables precise and reliable marker identification.Synchronized data processing minimizes the risk of misinterpretations and improves the efficiency of the tracking device, as received data packets can be evaluated quickly and accurately. This ensures continuous and stable operation even under challenging conditions.

[0104] The excitation unit can be configured to generate a pulsed alternating magnetic field. By generating a pulsed alternating magnetic field, the energy transfer to the marker can be precisely controlled by effectively exciting the resonance of the marker's resonant circuit. The pulsed structure allows the locating device to clearly distinguish between the excitation and reception phases of the modulated signal. This contributes to higher signal selectivity and more precise data transmission, especially in environments with interference. P609788PC00

[0105] The receiver unit may include means for synchronizing reception with a marker cycle. Synchronizing reception with the marker cycle results in time-aligned processing of the received data packets. This ensures that the tracking device correctly identifies and reliably evaluates the start and end points of the transmitted signal. This synchronization minimizes the probability of signal interference and misinterpretations, thereby improving data integrity.

[0106] The receiver unit may have at least one antenna, preferably three, arranged orthogonally to one another. Using three orthogonally arranged antennas enables the receiver unit to achieve an optimal received signal regardless of the marker's spatial orientation. This reduces the dependence of the reception quality on the antennas' orientation relative to each other and ensures consistent signal acquisition. This increases the reliability of data transmission, even if the marker position is difficult to access or constantly changing.

[0107] The receiver unit can be designed to reduce the positional dependence of the received signal through signal processing. By combining and analyzing the signals from multiple receiving channels, the dependence of the received signal strength on the relative position of the marker can be compensated for. This improves the receiving performance, as even weak or time-varying signals can be stabilized. This can lead to consistently high data transmission quality, even in dynamic or challenging localization environments.

[0108] The processor unit may be designed to analyze the modulated output signal multiple times in order to detect and compensate for transmission errors. Through multiple analyses of the modulated output signal, transmission errors can be detected and corrected via redundant evaluation. By comparing several received signals, deviations can be identified and corrected.

[0109] Faulty data bits are cleaned up. This improves the reliability of data extraction and ensures error-free marker identification.

[0110] The processor unit can be configured to analyze a redundant code of marker-specific identifiers. Analyzing a redundant code provides an additional layer of security for error detection and correction. A redundant code can identify disturbances in the data stream by verifying the consistency of the data structure. This enables the tracking device to perform reliable data extractions even in the event of sporadic disturbances or signal interruptions, thereby increasing the robustness of the tracking device.

[0111] The processor unit may be configured to perform synchronization with the sequence of the marker-specific identifier. Synchronization with this sequence ensures that the processor unit receives and processes data packets in the correct order, thus preventing timing errors such as misplaced or transposed data packets. This improves data extraction efficiency and ensures that the complete and unaltered sequence of the specific identifier is reliably recognized.

[0112] The tracking device and the method for using the tracking device can also be further specified by features of the first aspect of the disclosure and / or by features of the tracking system, and vice versa.

[0113] A further aspect of the present disclosure relates to a method for identifying a marker in a tracking environment of a tracking device. The method comprises several procedural steps. The method relates to the operation of an identifiable marker.

[0114] As a first step, a supply voltage can be obtained by rectifying the voltage of a marker resonant circuit. This voltage is generated by the P609788PC00 produced in the resonant circuit.

[0115] Resonant oscillation occurs after excitation by the locating device. Rectification is achieved using one or more diodes that convert the alternating current (AC) into a direct current (DC). Another implementation option involves the use of a rectifier IC, which ensures more stable and efficient DC operation. This provides a self-sufficient power supply for the electronic circuitry within the marker, eliminating the need for external power sources. This enables maintenance-free operation of the marker over extended periods and reduces the overall operating costs of the system.

[0116] It may be possible to provide a marker-specific identifier. This identifier can be output by a shift register in the form of a unique bit sequence. The bit sequence represents, for example, a serial number programmed during the marker's manufacturing process.

[0117] Alternatively, the identifier can be generated by electrically programmable memory chips, allowing for subsequent adjustment of the encoding. This enables unique identification of the marker. Providing a specific identifier ensures that the tracking device can reliably distinguish the marker from other markers, which is particularly important in applications with multiple markers in a tracking environment.

[0118] It can be provided that the decay of the marker resonant circuit is modulated into an output signal using the marker-specific identifier. This modulation is achieved by controlling the resonant circuit's capacitances or inductances, thereby selectively altering the resonant frequency. A switch, such as a transistor, can control the modulation process in real time. The output signal contains the modulating bit sequence and is radiated by the marker's antenna. Thus, the marker's specific identifier can be integrated into the output signal, ensuring reliable data transmission to the tracking device. Continuous modulation conserves energy in the resonant circuit, improving the stability and range of the signal transmission. P609788PC00

[0119] It can be provided that the output signal is used to identify the marker. The marker's antenna serves as the transmitter and transmits the modulated signal to the tracking device. The transmission is synchronized with the excitation of the resonant circuit, enabling the tracking device to receive and demodulate the signal without errors.

[0120] This ensures the complete transmission of the specific marker information. Providing the output signal in a coordinated manner helps minimize transmission errors and improves the overall efficiency of the identification process. This allows the tracking device to precisely evaluate the received signal and extract the data it contains.

[0121] It can be implemented that the marker-specific identifier is provided by a chained shift register with programmable bridges. The shift register enables the sequential output of the marker-specific identifier bits, allowing for precise modulation of the output signal. The use of programmable bridges provides a flexible and reliable method for configuring the identifier during marker manufacturing. These bridges can be selectively opened or closed to define the desired bit pattern. Permanent programming through physical separation of the bridges ensures that the identifier remains stable and unchanging even under demanding environmental conditions. This guarantees the unique and tamper-proof identification of the marker.

[0122] It can be provided that the marker-specific identifier is synchronized by cyclically reloading the linked shift register. This cyclical reloading ensures that the marker-specific identifier is output regularly and in the correct sequence. This improves synchronization between transmission in the marker and data processing in the locating device. At the same time, this function reduces the risk of synchronization errors, especially when the output signal is transmitted multiple times. The cyclic structure allows the locating device to access the correct identifier at any given time, increasing system reliability and improving error-free data extraction. P609788PC00

[0123] It can be implemented that the frequency shift is generated by switching on resonant circuit capacitances using a switch. Switching on resonant circuit capacitances enables fast and precise modulation of the marker resonant circuit's resonant frequency. The frequency shift can be controlled by an electronic switch that affects the capacitance in the resonant circuit. This implementation allows for continuous oscillation of the circuit, minimizing energy losses and improving the stability of the output signal. Since the modulation is purely capacitive, the resonant circuit amplitude remains nearly constant, which enhances signal quality and improves the system's range. Simultaneously, the use of electronic switches offers high switching speed and precise controllability, allowing for dynamic control of the modulation even in real time.

[0124] Another aspect of the present disclosure relates to an identifiable marker. The marker may include a marker resonant circuit, particularly in the form of an LC resonant circuit. The resonant circuit may consist of an inductor and a capacitor, which together define a resonant frequency. This frequency is tuned to the excitation frequency of the locating device in order to achieve maximum oscillation amplitude upon excitation by the alternating magnetic field. The inductor may be implemented as a ferrite antenna, while the capacitors may consist of fixed or switchable capacitors. The resonant circuit can provide efficient energy harvesting and signal processing. Through resonance, the signal strength is maximized, enabling both energy harvesting and signal modulation to be stable and reliable.

[0125] It may be provided that means are available to obtain a supply voltage by rectifying the voltage of the marker resonant circuit. These means may consist of one or more diodes that convert the AC voltage of the resonant circuit into a DC voltage. Alternatively, a rectifier IC may be used, which allows for more precise and stable voltage regulation. The resulting DC voltage is used to supply the electronic circuitry in P609788PC00.

[0126] A marker is used. This allows for autonomous operation of the marker, as the energy is derived directly from the oscillation of the excited resonant circuit. This eliminates the need for external power sources, increasing the marker's maintenance-free operation and service life.

[0127] The marker may include an electronic circuit configured to sequentially provide a marker-specific identifier. This circuit may contain a chained shift register that outputs the bit sequence of the specific identifier one after the other. The identifier is programmed during marker manufacturing by setting specific inputs of the shift register using programmable jumpers. Alternatively, non-volatile memory (EEPROM) may be used to store the identifier. This enables precise and unambiguous identification of the marker. The sequential provision of the identifier ensures that the data is output correctly and in the appropriate format for modulation.

[0128] It can be implemented that the oscillation of the marker resonant circuit is modulated into an output signal by adding resonant circuit capacitors with the marker-specific characteristic. Modulation is achieved by changing the resonant frequency of the circuit through the addition of these capacitors. An electronic switch, such as a transistor, controls this process in real time based on the data from the electronic circuit. The marker's specific characteristic can be integrated into the output signal. Frequency modulation ensures stable and continuous signal transmission because the circuit's oscillation is maintained despite the modulation. This significantly improves signal quality and the range of communication with the tracking device.

[0129] The marker resonant circuit may include a ferrite antenna. Due to its magnetically conductive material, the ferrite antenna enables high inductance and resonance quality in the resonant circuit. This allows for efficient energy absorption and radiation during excitation by the alternating magnetic field of the locating device. The compact design of the ferrite antenna P609788PC00

[0130] It also reduces the marker's space requirements and weight. The increased signal strength and improved coupling between the marker and the tracking device enhance the range and reliability of the signal transmission.

[0131] The electronic circuit can be configured to sequentially provide a marker-specific identifier using a monostable multivibrator (monostable multivibrator) and a chained shift register. The chained shift register enables the sequentially controlled output of the marker's bit sequence, thus precisely controlling the modulation of the output signal. The monostable multivibrator acts as a clock, ensuring that the bits are output evenly and synchronously. This structure guarantees that the data is provided in the correct order and with consistent timing. This can improve data integrity and facilitates the correct extraction of the identifier by the tracking device.

[0132] The electronic circuit may include a monostable multivibrator (monostable multivibrator) that controls the synchronization of the marker-specific identifier. The monostable multivibrator generates a precise, time-limited output signal that serves as a reference clock for synchronizing the transmission process. This control ensures that the time intervals between data packets and the sequence of transmitted bits are precisely maintained. As a result, the tracking device can correctly interpret the received signals and avoid timing errors such as shifted or incomplete data packets. This contributes to error-free and stable data transmission.

[0133] The electronic circuitry may be designed using CMOS technology to minimize power consumption. CMOS circuits can exhibit high energy efficiency because they only consume power during switching operations. This allows the marker to operate stably even at minimal supply voltages. CMOS technology supports voltages below 2 volts and reduces current requirements to the microampere level, which is particularly advantageous in passive systems that draw their power directly from the P609788PC00.

[0134] Relying circuit. This extends the operating time of the marker and ensures sustainable, autonomous operation.

[0135] The identifiable marker and the method for using the marker can also be further specified by features of the first aspect of the disclosure and / or by features of the tracking system and / or by features of the tracking device and the method for the tracking device, and vice versa.

[0136] The above can be summarized in other words and in a possible more concrete elaboration of the revelation as described below, whereby the following description is to be interpreted as not being restrictive for the revelation.

[0137] The idea is to use the energy from the excitation of the marker's resonant circuit to modulate the marker's response with an identifying code (serial number). The following functionalities are necessary for this:

[0138] • Extraction of the energy required for the operation of an electronic circuit from the excited oscillation of the marker resonant circuit.

[0139] • Modulation of the decay after excitation with the code.

[0140] • Sequence control - sequential provision of the code bits for modulation, identification of the start of the code.

[0141] • Error protection - Protection of the transmission against random bit corruption.

[0142] The required supply voltage is obtained by rectifying the voltage at the resonant circuit. The damping must be kept low and the quality factor high. Therefore, only a small portion of the resonant circuit's energy can be used to operate the circuit.

[0143] Two key aspects are

[0144] • minimizing the minimum operating voltage of the circuit,

[0145] • the lowest possible power consumption.

[0146] Both requirements are best met by using digital gate circuits in CMOS technology. These operate at less than 2 V and require supply currents in the microampere range. P609788PC00

[0147] According to the disclosure, modulation must influence a characteristic of the response signal sent by the marker without losing too much energy. For example, in the case of amplitude modulation (ASK), suppressing the response at zero would lead to a loss of energy.

[0148] One solution is the use of frequency modulation (FSK). Here, a 0 is encoded by shifting the nominal frequency in one direction, and a 1 by no shift. The shift can be easily achieved by adding capacitors to the resonant circuit. Due to the continuous oscillation, the energy in the resonant circuit remains constant regardless of the modulation.

[0149] The sequential provision of the bits to be modulated is achieved using a chained shift register. Each new excitation of the marker resonant circuit by the locator triggers a shift operation. In this way, all bits are read and modulated sequentially. The actual encoding of the serial number is accomplished by closed or open bridges at the inputs of the shift registers. In this implementation, the bridges are closed during manufacturing and are selectively opened by lasers. Block synchronization—reloading the shift registers after sending a complete serial number and a pause between two serial numbers to synchronize to the beginning—is performed by a monostable multivibrator (monofloop).

[0150] Interference can corrupt individual bits of the serial number during transmission. Two measures are in place to protect against this:

[0151] • Some (two to three) of the 24 bits are not used to encode the serial number, but as checkpoints. This allows a certain number of errors to be detected.

[0152] • The serial number is not read just once, but multiple times in succession. Multiple identical results would require bit errors occurring at the same position, which – especially in combination with the aforementioned measure – is extremely unlikely.

[0153] The search device (locating device) mirrors the functionalities of the marker:

[0154] • Pulsed excitation with alternating phases of excitation and reception P609788PC00

[0155] • FSK demodulation during the receive phase

[0156] • Synchronization at the serial number block level by evaluating the sequence enforced by the monostable multivibrator.

[0157] • Fault detection

[0158] The ferrite antenna used in the marker has a pronounced directional characteristic (dipole pattern). Depending on its relative orientation to the marker's search antenna, the coupling can vary from optimal (both antennas aligned parallel) to negligible (both antennas aligned perpendicular to each other). Consequently, the received signal strength depends not only on the distance but also significantly on the relative positions of the antennas.

[0159] In the prior art, a solution exists that uses a floating mount to ensure the marker's antenna remains horizontal at all times. This has several disadvantages:

[0160] • Floating bearings require fluid and therefore a correspondingly robust design of the housing and electronics.

[0161] • The concept requires two rotational degrees of freedom for the antenna and therefore a spherical housing. The space requirement is considerably greater than with the cylindrical shape of a fixed antenna.

[0162] The solution involves using three orthogonally aligned antennas in the locator. During the initial search phase, these antennas are alternately excited and used for reception. The antenna best aligned with the marker will receive the signal first. As the locator approaches the marker, the other antennas will also receive the signal. Depending on the field line pattern, the antenna with the best reception may change as the locator approaches. The dependence of the measured received field strength on the position of the marker antenna in space can be eliminated by creating a linear combination of the received field strengths of the three search antennas.

[0163] The range of the search technology is very limited due to the sharp decrease in magnetic field strength with distance (cube). To enable a first rough approximation of the position when searching for a specific marker, P609788PC00

[0164] The search device has an integrated GNSS module that is used during the placement and search for the marker:

[0165] Relocation:

[0166] • Laying markers

[0167] • Locate marker with search device; search device reads marker serial number

[0168] • Search device determines its own GNSS position

[0169] • The search device transmits its position and serial number to the cloud.

[0170] Search:

[0171] • Enter the serial number of the marker to be searched for

[0172] • The search device reads the marker's GNSS position from the cloud.

[0173] • The search device guides the user to the vicinity of the marker within the limits of GNSS accuracy. • Precise searching is performed using magnetic field strength.

[0174] • The search device ensures that the correct marker is located by reading the serial number during the search.

[0175] Furthermore, a computer program is provided, comprising instructions that, when executed by a computer, cause it to at least partially execute the procedure described above. The program code of the computer program can be in any form, in particular in a form suitable for tracking devices and / or markers. The above descriptions relating to tracking devices, tracking systems, and markers apply analogously to the computer program and vice versa.

[0176] The disclosure also includes combinations of features of the described embodiments. The disclosure therefore also includes realizations that each exhibit a combination of features from several of the described embodiments, provided that the embodiments have not been described as mutually exclusive.

[0177] The following are examples of the disclosure's implementation. This is illustrated by:

[0178] Fig. 1 schematically shows an embodiment of a location system according to disclosure 200;P609788PC00

[0179] Fig. 2 schematically shows an embodiment of a locating device 40 according to the disclosure;

[0180] Fig. 3 schematically shows an embodiment of a marker 1 according to the disclosure;

[0181] Fig. 4 schematically shows a flowchart of an embodiment of the method 100 as disclosed;

[0182] Fig. 5 schematically shows a flowchart of an embodiment of the method 300 according to the disclosure;

[0183] Fig. 6 schematically shows a flowchart of an embodiment of the method 400 according to the disclosure;

[0184] Fig. 7 schematically shows an oscillating circuit, an embodiment of a marker 1 according to the disclosure;

[0185] Fig. 8 schematically shows a shift register, an embodiment of a marker 1 according to the disclosure; and

[0186] Fig. 9 schematically shows a monoflop of an embodiment of a marker 1 according to the disclosure.

[0187] The exemplary embodiments described below are preferred embodiments of the disclosure. In these exemplary embodiments, the described components each represent individual features of the disclosure, which are to be considered independently of one another and which further develop the disclosure independently of one another. Therefore, the disclosure is intended to include combinations of features of the embodiments other than those shown. Furthermore, the described embodiments can also be supplemented by further features of the disclosure already described. P609788PC00

[0188] In the figures, identical reference symbols denote functionally equivalent elements.

[0189] The tracking system 200, shown only schematically in Figure 1, comprises a tracking device 20 and a plurality of identifiable markers 1. The number of markers 1 shown in Figure 1 is not to be interpreted as limiting for the purposes of the disclosure. The tracking system 200 can be configured to carry out the method 100 shown in Figure 4.

[0190] Figure 1 shows the tracking system 200 for identifying a marker 1 in a tracking environment of the tracking device 20. The tracking system 200 comprises the tracking device 20 and several markers 1 arranged along a cable 30. The markers 1 are intended to identify the individual cables 30 and / or determine their position. The cables 30 can also be other objects whose position is to be identified or determined. The tracking device 20 has means for generating a pulsed alternating magnetic field. These means can include an excitation unit 40. This excitation unit 40 generates the alternating magnetic field (downward-pointing arrow) that serves to excite the marker resonant circuit 3 of the markers 1. The marker resonant circuit can be designed as an LC resonant circuit.

[0191] Marker 1 contains an electronic circuit 2 designed to extract energy from the excited marker resonant circuit 3 by rectifying the voltage. This power supply allows Marker 1 to operate without an external power source. The electronic circuit 2 modulates the decay of the marker resonant circuit 3 with a marker-specific characteristic, which is transmitted via the output signal. The modulation is achieved by switching resonant circuit capacitors on or off, with the specific characteristic being provided sequentially. A monostable multivibrator (monoflop) can be used for this purpose to control the synchronization of the sequence. To minimize power consumption, the electronic circuit 2 can be implemented using CMOS technology. P609788PC00

[0192] The tracking device 20 comprises means for receiving the output signal modulated by modulation (arrow pointing upwards). These means can include a receiver unit 22, which comprises at least one antenna, preferably three antennas arranged orthogonally to each other. This arrangement serves to reduce the positional dependence of the received signal and enables the tracking device 20 to receive a stable signal regardless of the orientation of the marker 1.

[0193] After receiving the output signal "00", demodulation is performed in the tracking device 20 by a processor unit 23. This processor unit 23 is configured to process the received signal and extract the marker l-specific identifier from the signal. The tracking system 200 can ensure synchronization of the reception with the cycle of the monostable multivibrator of marker 1. Furthermore, transmission errors can be detected and compensated for by multiple evaluations of the signal. The analysis of redundant codes can further increase fault tolerance.

[0194] Advantages of the disclosed location system 200 include the fact that Marker 1 can be uniquely identified by their specific characteristics. This reduces the risk of confusion when searching for specific Marker 1 (and assigned objects (cables)), especially in complex environments with multiple Marker 1. Furthermore, the use of a passive Marker 1 with a self-sufficient power supply enables maintenance-free and sustainable operation. Precise modulation and synchronization improve the reliability of signal transmission, even under disruptive environmental conditions.

[0195] The tracking device 20 can also include a tracking module (e.g., GPS) that determines the position information of the markers 1 and stores it in a database. The database can be stored in a computer system and / or a cloud system. For this purpose, a communication link can be provided between the tracking system and / or the tracking device and the computer system and / or the cloud system for data transfer. The tracking system and / or the tracking device have corresponding interfaces.

[0196] and communication protocols. This information can be used to guide the user towards a desired marker 1. This enables a combination of coarse and precise location tracking.

[0197] Figure 2 shows a schematic representation of the locating device 20 for identifying a marker 1. The locating device comprises an excitation unit 21, a receiver unit 22, and a processor unit 23, which are arranged within a housing 40. The locating device 20 is also configured to perform the method 300 shown in Figure 5.

[0198] The excitation unit 21 includes means for generating a pulsed alternating magnetic field, which serves to excite a marker resonant circuit. This magnetic field is generated in regular pulses and tuned to the resonant frequency of the marker resonant circuit. The pulsed operation allows a clear separation between excitation and reception phases, which improves signal separation and offers energy savings.

[0199] The receiver unit 22 is configured to receive modulated output signals from the marker 1. The receiver unit 22 can include at least one receiving antenna, preferably three antennas arranged orthogonally to each other to reduce the positional dependence of the signal strength. The received signals are processed by the receiver unit 22 synchronously with the transmission cycle of the marker 1. This synchronization is achieved by a controller that is tuned to a monostable multivibrator in the marker 1.

[0200] Processor unit 23 is designed to process the received output signal. It is configured to extract marker 1-specific characteristics through demodulation. Demodulation is performed using the modulated signal, whereby the specific characteristic is recognized as the unique identifier of marker 1. Processor unit 23 can analyze the signal multiple times to detect transmission errors and compensate for them by comparing redundant signal segments. Furthermore, redundant code analysis methods can be employed, enabling additional error detection and correction. P609788PC00

[0201] Furthermore, the processor unit 23 can perform synchronization with the sequence of the marker l-specific identifier, thereby ensuring reliable data extraction. This is particularly advantageous in error-prone environments, as synchronization errors are avoided and data processing is stabilized.

[0202] This combination of excitation, reception, and processing ensures that markers can be reliably identified even in complex environments. Measures to reduce positional dependency and for synchronization improve the range and stability of signal transmission. The use of multiple antennas and redundancy analysis help to minimize interference and data loss.

[0203] Figure 3 shows a schematic representation of an identifiable marker 1. The marker 1 comprises a marker resonant circuit 3, which can be implemented, in particular, as an LC resonant circuit. This marker resonant circuit 3 is excited by an externally generated alternating magnetic field and serves for energy storage and signal modulation. In one embodiment, the marker resonant circuit 3 can include a ferrite antenna, which, due to its high resonance quality, enables efficient coupling with the alternating field of the locating device.

[0204] To power marker 1, means 4 are provided for generating a supply voltage. These means 4 generate the electrical energy by rectifying the voltage induced in the marker's resonant circuit 3. The generated voltage is used to power an electronic circuit 2 integrated into marker 1. This circuit 2 modulates the decay of the marker's resonant circuit 3 with a specific characteristic of marker 1 and provides the modulated output signal for identifying marker 1.

[0205] The electronic circuit 2 is configured to sequentially provide marker l-specific identifiers. A chained shift register P609788PC00 can be used for this purpose.

[0206] A device is used that outputs the bit sequence of the license plate number sequentially. Synchronization of the output is achieved by a monostable multivibrator (monostable multivibrator) that serves as a clock for the sequence. Electronic circuit 2 ensures that the data is provided in the correct order and with consistent timing.

[0207] To minimize power consumption, electronic circuit 2 is implemented using CMOS technology. This technology enables the circuit to operate even at low supply voltages and reduces energy consumption to the microampere level. This ensures autonomous and maintenance-free operation of the marker.

[0208] The decay modulation is achieved by selectively adding resonant circuit capacitances, which alter the resonant frequency of marker resonant circuit 3. This frequency modulation ensures that the marker 1's characteristic is reliably and stably integrated into the output signal. This continuous modulation contributes to maintaining signal strength and improving transmission range.

[0209] Figure 4 shows the method 100 for identifying a marker 1 in a tracking environment of a tracking device 20. In a first step 110 of the method 100, the tracking device generates a pulsed alternating magnetic field that excites the marker's resonant circuit 3. The marker's resonant circuit, which can be implemented as an LC resonant circuit, resonates upon excitation. In a further step 120, the marker 1 derives electrical energy from this resonance, which is used to power an electronic circuit 2. The energy is provided by rectifying the voltage in the resonant circuit, enabling the marker 1 to operate autonomously without an external power source.

[0210] After energy generation, the decay of the marker resonant circuit is modulated in a further step 130. In this step 140, a marker-specific identifier, such as a serial number, is integrated into the output signal. This modulation can be controlled by switching P609788PC00 on or off.

[0211] The resonant circuit capacitances are controlled by a switch. Various methods can be used to control the modulation process, such as frequency-shift keying (FSK), amplitude-shift keying (ASK), phase-shift keying (PSK), or continuous phase modulation (CPM). The specific identifier is provided by an electronic circuit in marker 1, which includes a shift register with programmable bridges. The synchronization of the modulation process is controlled by a monostable multivibrator (monostable multivibrator) that regulates the sequence of data cycles.

[0212] The modulated output signal is then transmitted from marker 1 to the tracking device 20 in a further step 140. The transmission is synchronized to ensure correct detection and processing of the data in the tracking device 20. After receiving the signal, the tracking device 20 extracts the marker 1-specific identifier by demodulation in a further step 150. To avoid transmission errors, the processor unit of the tracking device 20 analyzes the signal multiple times. If necessary, redundant data structures in the identifier are used to detect and correct erroneous transmissions. In extended implementations, the output signal is transmitted and evaluated at least twice to compensate for disturbances during data transmission.

[0213] In one embodiment, the marker resonant circuit can include a ferrite antenna with a high resonance quality. This antenna improves coupling with the magnetic field of the locating device and contributes to stable and efficient signal transmission, even over long distances or in weak field strengths.

[0214] Figure 5 shows the method 300 for identifying a marker 1 in a tracking environment of a tracking device 20. In a first step 310, a pulsed alternating magnetic field is generated by the tracking device 20. This field is tuned to the resonant frequency of the marker resonant circuit and excites the marker resonant circuit in the vicinity of the tracking device 20. The pulsed generation of the alternating field enables efficient control of the P609788PC00

[0215] Energy consumption of the tracking device and improves the separation between excitation and reception.

[0216] Following excitation, the tracking device 20 receives a modulated output signal in a further step 320, which is emitted by the marker 1 in response to the alternating magnetic field. The received signal contains a marker 1-specific identifier that serves to identify the marker 1. The receiving unit of the tracking device 20 is designed to reduce the positional dependence of the signal strength. This allows the tracking device 20 to receive a stable signal even when the marker 1 is oriented differently in space. The use of multiple receiving antennas or signal processing methods also contributes to improving the reception quality.

[0217] In a further step, the received output signal is processed. This includes demodulation, during which the marker l-specific characteristic is extracted. The signal processing is synchronized with the cycle of a monostable multivibrator located at marker 1. This synchronization ensures that the signal's data packets are processed in the correct temporal sequence, thus preventing errors due to timing shifts. To further increase the reliability of the data transmission, the received signal is detected and evaluated at least twice. By comparing the multiple received data, transmission errors can be detected and, if necessary, compensated for, which is particularly advantageous in environments with external interference.

[0218] The method ensures precise and error-free identification of marker 1, even under difficult reception conditions. The combination of synchronized signal processing, multiple evaluation, and reduction of position dependency improves the robustness and range of the tracking system 20.

[0219] Figure 6 shows the method 400 for identifying a marker 1 in a tracking environment of a tracking device 20. The method 600 begins in a first step 410 with obtaining a supply voltage through the P609788PC00

[0220] Rectification of the voltage in the marker resonant circuit 3. The marker resonant circuit 3 is first excited by a pulsed alternating magnetic field, which generates an alternating voltage within it. This voltage can then be rectified. The rectified voltage is used to power the electronic circuit 2 of marker 1, thus enabling the marker 1 to operate independently.

[0221] After the supply voltage is obtained, the electronic circuit 420 provides a marker-specific identifier in a further step. This identifier can, for example, include a serial number and is generated by a chained shift register with programmable bridges. The bridges define the bit pattern of the identifier, which is set during the creation of marker 1. The identifier is output cyclically, with continuous reloading of the shift register ensuring precise synchronization.

[0222] In the next step, 430, the decay of the marker resonant circuit is modulated with the marker's specific identifier. This modulation is achieved through a targeted frequency shift, controlled by switching resonant circuit capacitors on or off. An electronic switch handles the control, influencing the resonant frequency of the circuit according to the coded bit sequence of the identifier. This modulation method ensures stable and energy-efficient data transmission.

[0223] Finally, in a further step 440, the modulated output signal containing the marker l-specific identifier is provided. The continuous modulation ensures that the signal strength and transmission quality are maintained even at weak field strengths. The output signal is sent to the locating device 20, which can extract the identifier by demodulation to uniquely identify marker 1.

[0224] Method 400 ensures reliable signal modulation and data transmission, with synchronization optimized by cyclic reloading of the shift register. This is achieved through the use of resonant circuit capacitors and P609788PC00

[0225] An energy-efficient circuit technology enables stable and interference-free communication between marker 1 and locating device 20 of the locating system 200.

[0226] Figure 7 shows a circuit arrangement of the marker resonant circuit 3, which is used to identify the marker 1 in a tracking environment. On the left is a ferrite antenna FA1, which serves as part of the marker resonant circuit 3 and receives an external pulsed alternating magnetic field. The antenna generates an alternating voltage through resonance in the marker resonant circuit 3, which is used to power the circuit. This voltage is stabilized by the capacitors CI and C2 and influences the resonant frequency of the marker resonant circuit 3.

[0227] To modulate the decay, an additional capacitor C3 is switched on via transistor Q1, which acts as an electronic switch. Modulation is achieved using frequency-shift keying (FSK), in which the specific marker signal is encoded by frequency changes. A logical "0" is represented by shifting the resonant frequency in a specific direction, while a logical "1" is encoded by maintaining the original frequency. This frequency shift is achieved by selectively switching capacitor C3 on or off.

[0228] Frequency modulation offers the advantage that the energy in the resonant circuit remains constant regardless of the modulation. Unlike amplitude modulation (AM), where energy losses can occur due to signal suppression, frequency modulation keeps the resonant circuit amplitude constant. This contributes to stable and efficient data transmission.

[0229] Diodes D1 and D2 protect the circuit and stabilize the voltage in the resonant circuit against overvoltages. Resistor R2 controls the DC voltage (VDC) used to power the marker's electronic circuitry. An additional resistor, R5, regulates the current flow through transistor Q1 to ensure precise modulation control. Circuit P609788PC00

[0230] is designed to achieve minimal energy consumption, allowing the marker to operate maintenance-free for extended periods.

[0231] Overall, this circuit of Figure 7 enables precise modulation and reliable identification of marker 1, while maximizing energy efficiency through continuous oscillation in the resonant circuit.

[0232] Figure 8 shows a circuit arrangement with three cascaded 8-bit shift registers used to provide a marker-specific identifier. This arrangement allows the encoding of a serial number with a total of 24 bits. Each of the three shift registers has eight data inputs, DO to D7, at which the bits of the specific identifier are read.

[0233] The serial number is programmed via programming bridges LP1 to LP24, located at the inputs of the shift registers. After marker 1 is created, all bridges are initially closed. To set the serial number, one of the two conductor paths in each bridge is selectively cut using a laser. This method creates a permanent and tamper-proof bit pattern that enables the unique identification of marker 1.

[0234] The shift operation is triggered with each new excitation of the marker resonant circuit. The bits are read from the shift registers one after the other and modulated. This sequential output ensures that the data is provided in the correct order for modulating the output signal.

[0235] A monostable multivibrator (monoflop) controls block synchronization for data transmission. After a complete serial number is transmitted, the shift register is reloaded, and a short pause is observed to cleanly separate the transmission cycles. This synchronization prevents timing discrepancies and ensures that the tracking device can correctly receive and process the data. P609788PC00

[0236] The circuit's supply voltage is provided via the VDC connection. Capacitors in the circuit, such as the C-components connected to the VDC, stabilize the voltage supply and ensure the reliable operation of the shift registers. This energy-efficient circuit design enables maintenance-free and long-lasting operation of Marker 1, as no external power consumer such as a microcontroller is required.

[0237] The combination of programmable shift registers, laser-based bit programming, and monostable multivibrator-controlled synchronization ensures precise and reliable delivery of the encoded serial number. This architecture improves the efficiency and stability of data transmission and supports the unique identification of marker 1 in the tracking environment.

[0238] Figure 9 shows the circuit of a monostable multivibrator (monostable multivibrator) that controls the overall cycle of transmitting a complete serial number in marker 1. This circuit ensures the synchronization of the process by inserting a defined pause after each complete transmission of the marker 1-specific identifier and then reloading the shift register. This guarantees that the data is provided continuously and in the correct sequence.

[0239] The monostable multivibrator (monoflop) consists of components U1A and U1B, which are implemented as monostable multivibrators (monoflops) in the circuit shown. These components generate a precise time interval that controls the data transmission cycle. As soon as the output signal of a complete license plate has been sent, the monoflop is activated by a control voltage. Capacitors C9 and CIO stabilize the monoflop's time constant and ensure consistent clock control.

[0240] The shift register U2 is connected to the monostable multivibrator and receives a signal via the "load" line, which synchronizes the shifting process. The programming bridges LP1 to LP8 of the shift register determine the bit pattern of the marker, which is set during the marker's manufacturing process. Once a cycle is complete, the shift register is reloaded to store the next sequence of bits for the P609788PC00.

[0241] To provide modulation. The control signals "clk" and "load" ensure that the data output occurs in the correct order.

[0242] The VDC voltage supplies both the shift register and the monostable multivibrator circuit. Resistor R8 regulates the voltage at the monostable multivibrator, while additional components such as the filter capacitors stabilize the supply voltage. This configuration ensures precise and energy-efficient operation.

[0243] The monostable multivibrator (monoflop) plays a central role in the synchronization process, as it enables a clear separation between individual data cycles. This prevents timing overlaps or errors in signal processing within the tracking device. Synchronization improves the reliability of data transmission and minimizes the risk of serial number misinterpretations.

[0244] This circuit achieves stable and precise control of the data flow, which supports error-free identification of marker 1 even under difficult conditions.

[0245] Overall, the examples show how a tracking system can be deployed. P609788PC00

[0246] REFERENCE MARK LIST

[0247] 1 Marker

[0248] 2 electronic circuit

[0249] 3 Marker Oscillation Circle

[0250] 4 Means of generating a supply voltage 20 Locating device

[0251] 21 pathogen unit

[0252] 22 receiver unit

[0253] 23 processor units

[0254] 30 cables

[0255] 100 methods for identifying a marker; 110-150 procedural steps

[0256] 200 tracking system

[0257] 300 methods for identifying a marker 310-340 process steps

[0258] 400 Methods for identifying a marker 410-430 Procedure steps

Claims

P609788PC00 PATENT CLAIMS 1. Method (100) for identifying a marker (1) in a location environment of a location device (20), comprising: - Generating (110) a pulsed alternating magnetic field by the locating device (20) to excite a marker resonant circuit (3) of the marker (1), in particular an LC resonant circuit; - Gaining (120) electrical energy from the excited marker resonant circuit (3) to supply an electronic circuit (2) in the marker (1); - Modulating (130) the decay of the marker resonant circuit (3) with a marker (1) specific characteristic; - Transmitting (140) a modulated output signal with the marker (1) - specific characteristics from the marker (1) to the locating device (20), and - Identifying (150) the marker (1) by extracting the marker (1) specific identifier in the locating device (20) by demodulating the transmitted output signal.

2. Method (100) according to the immediately preceding claim, wherein the modulation is formed by controlling resonant circuit capacitances by means of a switch.

3. Method according to one of the preceding claims, wherein at least one of the following modulation methods comprising: FSK, ASK, PSK, CPM, is provided for the modulation.

4. Method (100) according to any one of the preceding claims, wherein the marker (1)-specific identifier includes a serial number of the marker (1) provided by a shift register with programmable bridges. P609788PC00 5. Method (100) according to one of the preceding claims, wherein the electronic circuit (2) is implemented in CMOS technology.

6. Method (100) according to one of the preceding claims, wherein the transmission of the output signal is carried out in a synchronized manner, and wherein the synchronization of the transmission is performed by a monostable multivibrator that controls the cycle of transmitting a complete marker (1)-specific identifier.

7. Method according to one of the preceding claims, wherein the marker resonant circuit (3) of the marker (1) has an antenna, and wherein the antenna is designed as a ferrite antenna.

8. Method according to one of the preceding claims, wherein the transmitted output signal is transmitted and / or evaluated at least twice in succession and the marker (1)-specific characteristic is extracted to detect and compensate for transmission errors caused by disturbances.

9. Method according to one of the preceding claims, wherein the marker (1) - specific identifier is provided with a redundant code.

10. Locating system (200) for identifying a marker (1) in a locating environment of a locating device (20), comprising: - a locating device (20) with: - Means for generating a pulsed alternating magnetic field; - Means for receiving a modulated output signal from a marker (1), and - Means for demodulating the received output signal to identify the marker (1); - a marker (1) with: - a marker resonant circuit. (3), in particular an LC resonant circuit, designed to be excited by the alternating magnetic field to P609788PC00 to obtain electrical energy to supply an electronic circuit (2); - the electronic circuit (2) designed to modulate a oscillation of the marker resonant circuit (3) with a marker (1) specific characteristic into the output signal, and - means for transmitting the output signal.

11. A tracking system (200) according to the immediately preceding claim, wherein the tracking device (20) comprises means for synchronizing the transmission of the output signal with a cycle of a monostable multivibrator of the marker (1).

12. A tracking system (200) according to any one of the preceding claims 10 and 11, wherein the tracking device (20) is configured to receive and evaluate the modulated output signal at least twice in order to detect and compensate for transmission errors.

13. Tracking system (200) according to any one of the preceding claims 10 to 12, wherein the tracking device (20) comprises a tracking module that determines position information of the marker (1) and wherein position information is linked in a database to store the marker (1) specific identifier and the position of the marker (1).

14. Locating system (200) according to any one of the preceding claims 8 to 12, wherein the marker (1) comprises a ferrite antenna which is formed as part of the marker resonant circuit (3).

15. Locating system (200) according to the immediately preceding claim, wherein means are provided for compensating the influence of the orientation of the antenna of the marker (1) in space on the strength of the received signal.

16. Method (300) for identifying a marker (1) in a location environment of a location device (20), comprising: - Generating (310) a pulsed alternating magnetic field; P609788PC00 - Receiving (320) a modulated output signal in response to the pulsed alternating magnetic field, and - Processing (330) the received output signal, comprising performing demodulation to extract a marker (1)-specific identifier for identification of the marker (1) from the received output signal.

17. Method (300) according to the immediately preceding claim, wherein the processing (330) of the received output signal comprises at least two detection and evaluation steps to detect and compensate for transmission errors.

18. Method (300) according to one of the preceding claims 16 and 17, wherein the reception (320) of the modulated output signal is carried out by means of a receiving unit designed to reduce the position dependence of the signal strength of the output signal.

19. Method (300) according to one of the preceding claims 16 and 118, wherein the received output signal is synchronized with a cycle of a monostable multivibrator in the marker (1) for synchronization of the processing.

20. Locating device (20) for identifying a marker (1), comprising: - an excitation unit (21) with means designed to generate a pulsed alternating magnetic field; - a receiver unit (22) configured to receive a modulated output signal; and - a processor unit (23) configured to process the received output signal in order to extract marker (1)-specific characteristics for identification of the marker (1) by demodulation.

21. Locating device (20) according to the immediately preceding claim, wherein the excitation unit (21) is configured to generate a pulsed alternating magnetic field. P609788PC00 22. Locating device (20) according to one of the preceding claims 20 and 21, wherein the receiver unit (22) comprises means for synchronizing the reception with a cycle of the marker (1).

23. Locating device (20) according to one of the preceding claims 20 to 22, wherein the receiver unit (22) has at least one antenna, preferably three antennas, and wherein the three antennas are arranged orthogonally to each other.

24. Locating device (20) according to one of the preceding claims 20 to 23, wherein the receiver unit (22) is configured to reduce the position dependence of the received signal by signal processing.

25. Locating device (20) according to any one of the preceding claims 20 to 24, wherein the processor unit (23) is configured to analyze the modulated output signal multiple times in order to detect and compensate for transmission errors.

26. Locating device (20) according to the immediately preceding claim, wherein the processor unit (23) is configured to analyze a redundant code of the marker (1)-specific identifier.

27. Locating device (20) according to any one of the preceding claims 20 to 26, wherein the processor unit (23) is configured to perform a synchronization with the sequence of the marker (1) specific identifier.

28. Method (400) for identifying a marker (1) in a location environment of a location device (20), comprising: - Gaining (410) a supply voltage by rectifying the voltage of a marker resonant circuit (3) of the marker (1); - Providing (420) a marker (1) -specific identifier; - Modulating (430) a decay of the marker resonant circuit (3) with the marker (1) specific characteristic into an output signal; P609788PC00 - Providing (440) the output signal for identifying the marker (1).

29. Method (400) according to the immediately preceding claim, wherein the provision (420) of the marker (1)-specific identifier is carried out by a chained shift register with programmable bridges.

30. Method (400) according to the immediately preceding claim, wherein the marker (1)-specific identifier is synchronized by a cyclic reloading of the linked shift register.

31. Method (400) according to any one of the preceding claims 28 to 30, wherein the frequency shift is generated by switching on resonant circuit capacitances by means of a switch.

32. Identifiable marker (1), comprising: - a marker resonant circuit (3), in particular an LC resonant circuit; - Means (4) for obtaining a supply voltage by rectifying the voltage of the marker resonant circuit (3), - an electronic circuit (2) designed to: - to provide a marker (1) specific identifier sequentially; - to modulate the oscillation of the marker resonant circuit (3) into an output signal by adding resonant circuit capacitances with marker (1) specific characteristics, and - to provide the output signal for identifying the marker (1).

33. Identifiable marker (1) according to the immediately preceding claim, wherein the marker resonant circuit (3) comprises a ferrite antenna.

34. Identifiable marker (1) according to one of the preceding claims 32 and 33, wherein the electronic circuit (2) is configured to sequentially generate a marker (1)-specific identifier by means of a monostable multivibrator and a P609788PC00 to provide a linked shift register.

35. Identifiable marker (1) according to any one of the preceding claims 32 to 34, wherein the electronic circuit (2) comprises a monostable multivibrator that controls a synchronization of the marker (1)-specific identifier.

36. Identifiable marker (1) according to any one of the preceding claims 32 to 35, wherein the electronic circuit (2) is implemented in CMOS technology to minimize power consumption.

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