METHOD AND DEVICE FOR DETERMINING THE POSITION OF OBJECTS

Abstract

Method for determining the position of objects, wherein objects with at least one linear and / or nonlinear material and / or structural property are introduced into a medium with linear and / or nonlinear properties, wherein the nonlinear material and / or structural properties of the medium do not match the nonlinear material and / or structural properties of the object, and - either a code-modulated signal is sent from a component to the object with at least one linear and / or non-linear material and / or structural property, and the signal is converted by the object into another signal modulated with a different code and sent by the object to at least one component, - or a non-code modulated signal is sent from at least one component to the object with at least one non-linear material and / or structural property, and the signal is converted by the object into a code-modulated signal and sent by the object to at least one component, wherein the at least one component is located outside the medium, and the noise component of the signal is removed from the code-modulated signals arriving at the at least one component, and the position of the object in one-, two- or three-dimensional directions is determined with the signal(s) thus corrected with a resolution of < 0.1 mm.

Description

[0001] The invention relates to the field of microelectronics and concerns a method for determining the position of objects, with which the position of objects from the micrometer scale can be determined under various environmental conditions with improved resolution, such as objects in gas lines or in plant, animal or human fluid circuits, as well as a device for implementing the method.

[0002] Various techniques for magnetic resonance imaging (MRI) are known. Magnetic resonance imaging is an imaging technique used primarily in medical diagnostics to visualize the structure and function of tissues and organs in the body. Physically, it is based on the principles of nuclear magnetic resonance (NMR) (Wikipedia, keyword "Magnetic Resonance Imaging").

[0003] US Pat. No. 5,402,786 A discloses a device for imaging magnetoacoustic resonances of bodies. It uses an ultrasound detector in combination with a weak magnetic field and a pulsed radiofrequency generator. A patient's body is partially exposed to a magnetic field and exposed to low-frequency acoustic pulses, generating low-frequency waves within the patient, which in turn cause magnetic resonances. The device allows the magnetoacoustic resonances to be easily located and measured.

[0004] A disadvantage of the state-of-the-art solutions is that, in particular, the localization of objects on the micro- to nanometer scale in various media is still inaccurate and thus neither desired locations can be localized accurately enough within the examination time nor can the localization and / or transport of objects to desired locations be realized within the examination time.

[0005] The object of the present invention is to provide a method for determining the position of objects, in particular objects on the micrometer to nanometer scale, in a medium, with which the position of the objects is determined with high accuracy and at least within the investigation period, and the object is further to provide a simple and cost-effective device for implementing the method.

[0006] The object is achieved by the invention defined in the claims. Advantageous embodiments are the subject of the dependent claims, whereby the invention also includes combinations of the individual dependent claims in the sense of an AND connection, as long as they are not mutually exclusive.

[0007] The solution according to the invention makes it possible for the first time to provide a method for determining the position of objects, particularly objects on the micrometer to nanometer scale, in a medium, with which the position of the objects can be determined with high accuracy and at least within the examination period. Likewise, a simple and cost-effective device for implementing this method is known for the first time.

[0008] This is achieved by a method for determining the position of objects, in which objects with at least one linear and / or non-linear material and / or structural property are introduced into a medium with linear and / or non-linear properties, whereby the non-linear material and / or structural properties of the medium do not match the non-linear material and / or structural properties of the object.

[0009] Furthermore, at least one component is arranged outside the medium.

[0010] Depending on the respective linear and / or non-linear material and / or structural properties of the object and the medium surrounding the object, the invention provides three variants for sending signals to and from the object and for processing them.

[0011] In case a signal modulated with a code is sent from a component to the object with at least one linear and / or non-linear material and / or structural property, the signal is converted by the object into another signal modulated with a different code and subsequently sent from the object to at least one component.

[0012] In case a non-code-modulated signal is sent from at least one component to the object with at least one non-linear material and / or structural property, the signal is converted by the object into a code-modulated signal and sent from the object to at least one component.

[0013] Finally, in case an object with linear and / or non-linear material and / or structural properties generates a signal modulated with a code, this signal is sent to at least one component.

[0014] As soon as a code-modulated signal has arrived at at least one component, the noise component of the signal is removed and the position of the object in one, two or three-dimensional direction is determined with the thus corrected signal with a resolution of < 0.1 mm.

[0015] The processing of the code-modulated signal in the component can also be referred to as correlation in signal processing, in which a relationship is established between two or more temporal or spatial functions (Wikipedia, keyword correlation (signal processing)).

[0016] Objects can be located as gaseous, liquid or solid objects that are located in a gaseous, liquid or solid medium.

[0017] For example, the objects according to the invention can be 2D or 3D structures, such as atoms, molecules, droplets or solid particles located in a liquid or in a gas stream, as well as gas bubbles in a liquid, or cancer cells in a human or a drug in the bloodstream of a human or animal, or like mesoscopic robots or like components of all kinds. The objects must be capable of producing and / or modulating and receiving and / or transmitting complex signals.

[0018] The objects according to the invention are in any case located in a medium.

[0019] According to the invention, it is necessary that at least one component is arranged in the desired dimensional direction relative to the object to determine a one-dimensional position of an object, at least two components are arranged in the desired dimensional direction relative to the object to determine a two-dimensional position of an object, and at least three components are arranged in the desired dimensional direction relative to the object to determine a three-dimensional position of an object, wherein the components are each arranged outside the medium.

[0020] All objects according to the invention have dimensions in the micro- to nanometer scale and can either not be localized with prior art solutions or not with sufficient accuracy and speed.

[0021] The inventive localization of the objects refers to the localization in one-, two- and / or three-dimensional directions.

[0022] In the context of the present invention, nonlinear material and structural properties are understood to mean that an external excitation, such as a magnetic or acoustic field, causes a response in an object, such as temperature changes in the object, expansion of the object's material, changes in the object's magnetic properties, or structural changes. These changes in the properties of the object's material and / or structure can be one of the nonlinear functions of the external excitation, such as a polynomial function, a polyline function, or a saturation function, or combinations thereof. These functions can exhibit hysteresis.

[0023] Also of particular importance according to the invention is that, according to the invention, the objects are located in a medium with linear and / or non-linear properties, the material and structural properties of which do not correspond to the non-linear material and / or structural properties of the object.

[0024] In the context of this invention, linear properties are to be understood as the opposite of non-linear properties, i.e. that no response is elicited in an object in response to an external stimulus, or a response is elicited in the object which shows no response to an external stimulus, or a proportional response with a constant proportionality factor in the range of the amplitude of the external stimulus.

[0025] An advantageous solution according to the invention is when the position of objects with exclusively non-linear material and / or structural properties is determined and / or the position of objects in media with exclusively linear material and / or structural properties is determined.

[0026] Furthermore, it is necessary according to the invention that the objects receive, modulate and transmit and / or generate and transmit signals, advantageously electromagnetic, acoustic, mechanical or optical signals or waves.

[0027] In the case of code-modulated or non-code-modulated signals received by the object, it is of particular importance according to the invention that these are converted by the object into other code-modulated signals.

[0028] For example, received code-modulated or non-code-modulated magnetic signals from the object can be converted into acoustic signals, or received code-modulated or non-code-modulated acoustic signals from the object can be converted into optical signals.

[0029] It is advantageous to have a medium that transmits the signals to and from the object.

[0030] According to the invention, the signals received and transmitted by the objects have been transmitted and / or are received by at least one component. Any technical element that transmits and / or receives signals, advantageously electromagnetic, acoustic, mechanical, or optical signals or waves, can be used as a component.

[0031] With just one component, the position of the object can be determined in a one-dimensional direction. With two or three or more components, the position of the object can be determined in a two- or three-dimensional direction, whereby, of course, the components must also be arranged in the corresponding spatial directions.

[0032] After code-modulated signals from the objects have arrived at the component, they are correlated there by removing the noise component of the signals and using the thus corrected signals to determine the position of the object in one, two or three-dimensional directions with a resolution of < 0.1 mm in each case.

[0033] According to the invention, the removal of noise from the received code-modulated signals is necessary in order to be able to extract information about the position of the object from the code-modulated signals emitted by the objects.

[0034] At the same time, the accuracy of object positioning can be further improved by longer signal recording or due to a special form of the signal, such as a phase shift.

[0035] For example, the code correlation with the removal of noise from the signals received at the components is carried out as follows.

[0036] The code-modulated signal emitted by the object exhibits a specific shape or other characteristics due to the code modulation. For example, the code-modulated signal is modulated with a quasi-random noise sequence code. One such quasi-random noise sequence code is the Gold code, which is characterized by a strong autocorrelation coefficient. The cross-correlation coefficient between such Gold codes is also large. The length of the Gold code in bits, the strong autocorrelation coefficient, its uniqueness, and the transmission speed (bit / s or chips / s) of the code determine the phase resolution, which, in turn, determines the position of the object as a function of the signal propagation speed in the medium.

[0037] The stronger the code's autocorrelation coefficient, the higher the cross-correlation value between the code-modulated signal emitted by the component and the code-modulated signal received back by the object. A higher cross-correlation value between the code-modulated signal emitted and the code-modulated signal received back by the object relative to the signal noise results in greater signal noise, allowing a larger gain coefficient to be determined, thus allowing the object's position to be determined more accurately.

[0038] The code for the correlation of the signals should be modulated and compressed in such a way that a modulation technique such as phase shift keying (PSK), amplitude shift keying (ASK), quadrature amplitude modulation (QAM), frequency modulation (FSK) by, for example, orthogonal frequency division multiplexing (OFDM) or non-orthogonal frequency division multiplexing (NOFDM) can be applied.

[0039] Such modulation will transmit one or more codes at transmission speeds across a number of carrier frequencies with bandwidths. This is particularly advantageous, even for ultrasound techniques, for example, since phase resolution can be achieved in the sub-signal wavelength range, independent of the signal length.

[0040] However, the resolution can be further improved by applying additional digitization in the region of the correlation peak. The higher the autocorrelation coefficient (the height of the peak), the higher the correlation signal of the noise, and the more digitization of the peak is possible.

[0041] In such a case, the resolution can be improved to sub-bit or sub-chip levels after demodulation and data processing. Further improvements can be achieved through correlation and phase determination of the frequency carriers.

[0042] If the signal is in the form of a quasi-random noise sequence, the influence of the noise caused by the transmission channel will disappear and / or can be eliminated by an appropriate code correlation with an appropriate length and with a sufficiently strong autocorrelation coefficient.

[0043] However, the code can be designed in such a way that the same signal can have different resolutions at the same time.

[0044] This is useful for determining the phase shift of an object using code detection methods, which can improve the speed of the positioning process. However, the required code(s) can be introduced into the signal (sent by the object or generated by the object) during the nonlinear process associated with interactions of the external excitation (which does not carry the initial code) with the material or structure of the object.

[0045] Furthermore, the object is achieved according to the invention by a device for determining the position of objects, wherein the device consists of an object in a medium and of at least one component arranged outside the medium and of a device for processing code-modulated signals to remove the noise component of the signal and to determine the position of the object in one-, two- or three-dimensional direction from the corrected signal with a resolution of < 0.1 mm.

[0046] If only one component is present, the position of the object can be determined in a one-dimensional direction only. If two or more components are present in the respective directions, the position of the object can also be determined in a two- or three-dimensional direction.

[0047] With this device according to the invention, the method according to the invention can be carried out with all its advantageous embodiments.

[0048] The present invention differs from all prior art solutions in particular in that the signal source is the object whose position is to be determined and which is located within a medium, and its position cannot obviously be determined in a simpler other way.

[0049] According to the state of the art, the position of objects on the micrometer to nanometer scale within a medium can only be determined up to a local resolution of > 0.1 mm. The signal source is located outside the medium. With this type of signal recording, the signal emitted by a signal source outside the medium and the signal reflected by the object within the medium have the same shape, but not the same phase and amplitude. At the same time, unwanted reflections or adsorptions in the medium surrounding the object influence the incoming signal in the same way, further reducing the resolution of the object's location.

[0050] According to the invention, the object is now, for the first time, the signal source for a code-modulated signal, so that neither phase shifts nor unwanted reflections or adsorptions occur or need to be taken into account. According to the invention, the signal source can also be located outside the medium; however, even in these cases, the signals received by the object are modulated and converted, advantageously code-modulated, and then, according to the invention, have a different form than the signals emitted by the signal source.

[0051] In case the object itself emits a signal, knowledge of the shape of the signal is not necessary for further processing.

[0052] For example, according to the invention, the signal emitted by a transmitter is transmitted to the object using a magnetic field. The object then modulates the received magnetic signal and converts it into an acoustic signal, which then leaves the medium and is received by one or more components, analyzed, and correlated. In this way, the undesirable effects of the medium on the transmitted and received signal can be eliminated.

[0053] By generating different signals with different shapes (harmonic, pulsed, noise-like) independent of the shape of the emitted signal, the invention allows, on the one hand, to avoid undesirable effects of the medium on the signal emitted by the object and, on the other hand, to improve the resolution of the sub-signal length accuracy to even 1 µm or less. The inventive method makes it possible to determine the position of objects on the micrometer to nanometer scale in media with significantly improved accuracy and speed.

[0054] The invention is explained in more detail below using several exemplary embodiments. Example 1

[0055] The object is made of a magnetostrictive material and has a specially designed hysteresis BH loop as a magnetic linear property.

[0056] The object is located in an aqueous solution as a medium with nonlinear properties for the transmission of acoustic waves.

[0057] A component that is both a transmitter for magnetic signals and a receiver for acoustic signals sends a harmonic magnetic excitation signal from outside the medium to the object, which is modulated with a broadband code.

[0058] The object receives the broadband magnetic signal and modulates / converts the broadband magnetic signal into a complex broadband acoustic signal with a gold code modulated signal as a response and sends it to the device outside the medium.

[0059] Since the highly unique acoustic signature of the Gold Code is known, this signature can be recognized by the receiver component, and the phase of the signal modulated with the Gold Code can be determined by the receiver component after the cross-correlation demodulation procedure. By knowing the phase of the Gold Code, the signal can be determined very precisely, and the noise in the signal is removed using known mathematical relationships.

[0060] Due to the presence of a component outside the medium, the position of the object in one direction can be determined very precisely with a high resolution of 0.025 mm from the signal after removing the noise. Example 2

[0061] An object made of a composite of different metallic materials exhibits a magnetoacoustic nonlinear property characterized by a specially formed hysteresis BH loop.

[0062] The object is located in a gas stream that has a different nonlinear property than the object.

[0063] From three positions outside the gas flow in the x-, y- and z-direction, three components act as transmitters / receivers, each sending an unmodulated magnetic signal.

[0064] The object modulates and converts these signals into broadband acoustic signals with a signature, so that these signals are provided with the specific signature, and sends these signals back to the transmitter / receiver components.

[0065] By knowing the modulated signature of the object, the signal can be detected very precisely by the receiver components after the cross-correlation demodulation procedure and the noise of the signal can be removed from the signal using known mathematical relationships.

[0066] Due to the presence of three components outside the medium, the position of the object in three-dimensional direction can be determined very precisely with a high resolution of 0.05 mm from the signals after noise removal. Example 3

[0067] An object made of a composite of different metallic materials exhibits an acoustoacoustic nonlinear structural property.

[0068] The object is located in a liquid with linear properties as a medium.

[0069] From three positions outside the liquid in the x, y and z directions, three components act as transmitters / receivers, each sending an unmodulated acoustic signal.

[0070] The object modulates and converts these signals into broadband acoustic signals with a signature, so that these signals are provided with the specific signature, and sends these signals back to the transmitter / receiver components.

[0071] By knowing the modulated signature of the object, the signal can be detected very precisely by the receiver components after the cross-correlation demodulation procedure and the noise of the signal can be removed from the signal using known mathematical relationships.

[0072] Due to the presence of three components outside the medium, the position of the object in three-dimensional direction can be determined very precisely with a high resolution of 0.01 mm from the signals after noise removal. Example 4

[0073] A robot as a self-operated autonomous mesoscopic system, with dimensions in the micrometer range, is located as an object in a bloodstream as a medium with nonlinear acoustic properties.

[0074] The robot generates an acoustic signal modulated with a gold code signature.

[0075] This signal is sent to a component acting as a receiver outside the bloodstream, where it is very precisely recognized by the knowledge of the robot's gold code signature after demodulation by the receiver component, and the noise of the signal is removed from the signal using known mathematical relationships.

[0076] By using the receiver component outside the medium, the position of the object in one-dimensional direction can be determined very accurately with a high resolution of 0.05 mm from the signal after removing the noise and determining the signal phase. Example 5

[0077] A robot as a self-operated autonomous mesoscopic system with dimensions in the micrometer range is located as an object in a bloodstream as a medium with nonlinear optical properties.

[0078] The robot generates an optical signal modulated with a signature.

[0079] This signal is sent to a component acting as a receiver outside the bloodstream and is recognized there very precisely due to the knowledge of the robot's signature after demodulation by the receiver component and the noise of the signal is removed from the signal using known mathematical relationships.

[0080] By using the receiver component outside the medium, the position of the object in one-dimensional direction can be determined very accurately with a high resolution of 0.005 mm from the signal after removing the noise and determining the signal phase.

Claims

[1] Method for determining the position of objects, in which objects with at least one linear and / or non-linear material and / or structural property are introduced into a medium with linear and / or non-linear properties, wherein the non-linear material and / or structural properties of the medium do not match the non-linear material and / or structural properties of the object, and - either a signal modulated with a code is sent from a component to the object with at least one linear and / or non-linear material and / or structural property and the signal is converted by the object into another signal modulated with a different code and sent from the object to at least one component, - or a non-code modulated signal is sent from at least one component to the object with at least one non-linear material and / or structural property and the signal is converted by the object into a code modulated signal and sent from the object to at least one component, wherein the at least one component is arranged outside the medium, and the noise component of the signal is removed from the code modulated signals arriving at the at least one component and the position of the object in one, two or three-dimensional direction is determined with a resolution of < 0.1 mm using the signal(s) thus corrected. [2] Method according to claim 1, wherein the position of gaseous, liquid or solid objects in a gaseous, liquid to solid medium is determined. [3] Method according to claim 1, in which the position of objects with dimensions in the mm to nm range is determined in the form of 2D or 3D structures. [4] Method according to claim 1, in which the position of objects is determined with exclusively non-linear material and / or structural properties. [5] Method according to claim 1, in which the position of objects in media with exclusively linear material and / or structural properties is determined. [6] Method according to claim 1, wherein the objects emit electromagnetic, acoustic, mechanical or optical signals and / or convert received electromagnetic, acoustic, mechanical or optical signals into other electromagnetic, acoustic, mechanical or optical signals. [7] Method according to claim 1, in which at least one component is arranged to determine a one-dimensional position of an object, at least two components are arranged to determine a two-dimensional position of an object and at least three components are arranged to determine a three-dimensional position of an object, wherein the components are each arranged in the desired dimensional direction relative to the object. [8] Method according to claim 1, wherein a medium is present which transmits at least the signals from and to the object. [9] Device for determining the position of objects using a method according to at least one of claims 1 to 8, consisting of an object in a medium and of at least one component arranged outside the medium and of a device for cross-correlating code-modulated signals to remove the noise component of the signal and to determine the position of the object in one, two or three-dimensional direction from the corrected signal with a resolution of < 0.1 mm.