AND/OR DIAGNOSIS

FIELD OF THE INVENTION

The present invention relates to a medical device for magnetic field treatment and/or diagnosis. Further, the present invention relates to a system , a method for operating a medical device, and to a computer program element.

BACKGROUND OF THE INVENTION

In medical technology it is known that at least some diseases, particularly if they are triggered by pathogens, such as bacteria, parasites, fungi, viruses, etc., which may be built from proteins, DNA, cells, etc., in a human or animal body may be treated by a broad- frequency magnetic field. This may affect proteins, DNA, cells, etc., in order to weaken or kill the pathogen. Technically, however, it is a challenge to provide a suitable magnetic field in a reliable way, particularly to provide an electric current at a desired frequency and/or level.

SUMMARY OF THE INVENTION

There may, therefore, be a need for providing an improved means for providing a broad-frequency magnetic field. The object of the present invention is solved by the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims. According to a first aspect, there is provided a medical device for magnetic field treatment and/or diagnosis. The device may be configured to provide one or more specific magnetic waveforms and/or magnetic intensities. The medical device comprises: a controller, comprising at least a pulse-width modulation (PWM) generator configured to generate a number of PWM signals corresponding to a control program comprising information on the one or more specific magnetic waveforms and/or magnetic intensities to be provided; an H-bridge, comprising a number of switches connected to the controller to receive the number of PWM signals and configured to be selectively switched on and off to generate an electric current, caused by the number of PWM signals, through the H-bridge, ; and a coil, connected to the number of switches, and configured to be driven by the electric current and to generate, in response to the electric current, the one or more specific magnetic waveforms and/or magnetic intensities to be provided.

In this way, the medical device may provide a broad-frequency magnetic field. Further, this configuration allows a high power efficiency, a high frequency magnetic spectrum, and requires merely few electrical components.

As used herein, the controller may be broadly understood as an arrangement of electrical and/or electronic components, such as a Field Programmable Gate Array (FPGA), a processor and/or microprocessor, a memory, data interfaces, etc., and/or software components that can perform control of the medical device based on at least the control program.

Further as used herein, the H-bridge may be broadly understood as an electronic circuit configured to switch a polarity of a voltage applied to a load. Optionally, the number of PWM signals are voltage signals.

For example, the number of switches may be of a metal-oxide-semiconductor field- effect transistor (MOSFET) type.

As used herein, the subject to be exposed to the magnetic field, i.e. to the one or more magnetic waveforms and/or intensities, may be broadly understood, and may, for example, be a human or animal, a body thereof or a part of it. Alternatively, the subject may also be an in vitro substance, e.g. a pathogen, an organism, or the like, such as one cultivated in a Petri dish, test tube, or the like, wherein the substance may be subjected to the magnetic field. Additionally or alternatively, the subject may be an interior room that is to be disinfected and/or sterilized. In at least some embodiments, the interior may also be a container for receiving medical instruments to be disinfected and/or sterilized.

For example, the magnetic waveform to be provided may be selected from square, DC, saw tooth, sine, triangle, and/or a combination thereof. Likewise, a waveform of the electric current driving the coil and causing the magnetic field may be selected from square, DC, saw tooth, sine, triangle, and/or a combination thereof.

Optionally, the PWM generator may be further configured to selectively control, based on the control program, the number of switches to be switched on or off to generate, by applying the number of PWM signals, the electric current through the coil in a specific way according to the control program to generate the one or more specific magnetic waveforms and/or magnetic intensities to be provided. For example, the medical device may further comprise a number of switch drivers, connected to the PWM generator, and configured to switch the corresponding switch on or off in accordance with the PWM signals and/or the control program. In this way, the current flow can be switched and/or changed quickly by short switching times.

Optionally, the PWM generator may be further configured to alternately switch on or off, based on the control program, two switches of the number of switches arranged diagonally to each other at a time, thereby directing the electric current through the coil in a specific way to generate the one or more specific magnetic waveforms and/or magnetic intensities to be provided. In this way, the current flow can be switched and/or changed quickly by short switching times.

Optionally, the PWM generator may be further configured to control, based on the control program, the number of switches to be switched on or off to establish a specific duty- cycle D of the number of PWM signals. Further optionally, the specific duty-cycle D may determine at least a signal shape of the electric current through the coil, thereby resulting in the one or more specific magnetic waveforms and/or magnetic intensities to be provided. The duty cycle D may be defined as a ratio between an active pulse and a PWM period, which may be expressed by D = wherein ton is an active pulse time and Ts is a PWM period time.

According to an embodiment, a frequency of the generated electric current may be between direct current (DC) to 30 kHz. Optionally, the frequency of the generated electric current may be varied during execution of the control program. In this way, e.g. a pathogen can be harmed minimally invasively or non-invasively.

In an embodiment, an amplitude of the generated electric current may be between 0,1 A and 10 A. In this way, a broad-frequency magnetic field can be provided, by which, for example, a pathogen can be harmed minimally invasively or non-invasively.

In an embodiment, the H-Bridge and the coil may form an integral, i.e. one-piece, applicator. For example, the applicator may be formed as a pad, electrode-like, etc. In this way, the medical device may be used for magnetic field therapy and/or treatment applications, by applying the applicator in direct contact or by arranging it close to the subject.

In an embodiment, the medical device may be configured to apply the one or more specific magnetic waveforms and/or intensities to the subject for magnetic field treatment and/or magnetic field therapy.

According to an embodiment, the control program forms a magnetic field treatment program and/or a magnetic field therapy program to be applied to the subject. In other words, the control program may comprise at least a definition of an electric current through the coil that can generate the desired magnetic field. In this way, a specific therapy or treatment program can be applied to the patient using the coil.

In an embodiment, the coil forms an applicator coil and/or a therapy coil, configured to be applied on or around the subject to provide the one or more specific magnetic waveforms and/or intensities to the subject. In this way, a specific therapy or treatment program can be applied to the patient using the coil.

According to an embodiment, the information on the one or more specific magnetic waveforms and/or magnetic intensities of the control program comprises a sequence of signal indicators indicating whether one or more signal parameters, used to generate the one or more specific magnetic waveforms and/or magnetic intensities to be provided, remain unchanged or are to be changed.

In other words, the medical device, e.g. the controller, receives only one or more signal parameters that describe the corresponding analog signal to be output by the signal source, instead of receiving the control program, e.g. therapy and/or treatment program, sample by sample, i.e. in sample by sample data. For example, the one or more signal parameters may comprise one or more of a signal shape or waveform, amplitude, frequency, and signal duration. The medical device may receive the control program, which may correspond to the therapy program to be applied to the subject, and may generate, based on the control program, a corresponding control signal to control the signal source to generate and/or output the corresponding analog signal. In this way, by utilizing only the signal parameters instead of sample by sample data, the amount of data to generate the analog signal may be reduced. In an embodiment, the medical device, e.g. the controller, is further configured to provide the one or more signal parameters such that the signal parameters are provided with signal parameter information indicating over which application time the one or more signal parameters remain unchanged or to be changed. In other words, the medical device utilizes only information of length of time with regard to changes or non-changes of the one or more signal parameters according to a predefined function, instead of also specifying the exact signal parameters for each time point. This mechanism may also referred to as time slot concept, in which the time slot is defined as the length of time that the one or more signal parameters remain unchanged or are changed according to a predefined function. Thereby, the time slot may be further defined or dimensioned with a length of time within which a reaction or response of the subject, i.e. the body or the substance, can be expected or even recognized, i.e. a reaction or response can be measured. By way of example, the time slot may have a length of time in the range of Milliseconds (ms), but is not limited thereto. In this way, the size of data files of the control program may be reduced, as it only comprise a reduced amount of information.

According to an embodiment, the sequence of signal indicators may comprise at least a first signal indicator associated with a first specific magnetic waveform and/or magnetic intensity and a second signal indicator associated with a second specific magnetic waveform and/or magnetic intensity different to the first specific magnetic waveform and/or magnetic intensity. In other words, the characteristic of the electric current, i.e. the driver signal, may be varied from time slot to time slot, i.e. from signal indicator to signal indicator.

In an embodiment, the one or more signal parameters are selected from: a time slot duration indicating that the signal parameter remain unchanged during the time slot duration, an amplitude of the electric current, an offset of the electric current, a frequency of the electric current, a duty cycle if the waveform of the electric current is square, and a waveform type.

According to an embodiment, the waveform type is selected from: sine, triangle, saw-tooth, square, DC, and pulse. In this way, the magnetic field may have a broad-frequency spectrum.

In an embodiment, the controller may further comprise a signal generator, arranged upstream to and connected to the PWM generator, and configured to generate, based on the control program, a source signal, corresponding to the one or more specific magnetic waveforms and/or magnetic intensities to be provided, to be used by the PWM generator to generate the number of PWM signals. For example, the signal generator may be configured to generate a specified PWM duty cycle in order to obtain a signal shape of the electric current through the coil that is suitable to provide the one or more specific magnetic waveforms and/or magnetic intensities.

By way of example, the signal generator may further comprise a phase generator unit configured to generate a phase information to be provided to a waveform generator unit, based on a frequency information. For this purpose, the phase generator unit may be configured to receive one or more input signals selected from: a clock signal, a reset signal, a variation type, a frequency information, and a variation step. The clock signal may also be referred to as PWM clock, which may be a global clock. It may provide a clock signal in the kilohertz range, e.g. in the range of 440 kilohertz (kHz) to 520 kHz, preferably in the range of 460 kHz to 500 kHz, further preferably in the range of 480 kHz to 490 kHz, and most preferably of about 488 kHz. The variation type may indicate a variation of the source signal to not establish a variation or to establish a variation to be linear, exponential or logarithmic. The variation step may be associated with the above time slot duration, and may have 1024 samples per period. The phase generator unit may output one or more of a phase information and a frequency information to be used by a frequency compensation unit.

Further, by way of example, the signal generator may further comprise a waveform generator unit configured to generate the one or more waveforms to be included in the source signal and required to generate the specific magnetic field. The waveform generator unit may be configured to receive one or more input signals selected from: a clock signal, a phase information, a duty cycle, and a waveform information. The clock signal may also be referred to as PWM clock, which may be a global clock. It may provide a clock signal in the kilohertz range, e.g. in the range of 440 kHz to 520 kHz, preferably in the range of 460 kHz to 500 kHz, further preferably in the range of 480 kHz to 490 kHz, and most preferably of 488 kHz. The phase information may be provided, e.g. by the above phase generator unit, in a manner, e.g. in a bitstream, to allow to access a look-up table (LUT) as explained below. The duty cycle may be provided by a duty cycle variation unit. The waveform information may be derived from the control program. The waveform generator unit may be configured to output a sample, e.g. as a bitstream, to be provided to the PWM generator as the source signal.

According to an embodiment, the signal generator may be further configured to derive from the control program phase information and waveform information, and to derive, from at least one look-up table (LUT), assigning the phase information and the waveform information to a specific waveform, a specific waveform, and to generate, using the derived specific waveform, the source signal. For example, the signal generator, e.g. the phase generator unit and/or the waveform generator unit, may receive at least the phase information and waveform information and may, based on this, access the at least one LUT, which comprises predefined and/or user defined data regarding the specific waveform for one or more different phase information and waveform information. Then, the source signal may be generated based on the specific waveform derived from the LUT. In this way, the computation time for determining the specific waveform may be reduced.

According to an embodiment, the signal generator may be further configured to utilize or may further comprise a comparator, configured to compare a current phase information with a duty cycle value, to generate a specific square waveform for generating the source signal.

In an embodiment, the medical device may further comprise a detection circuit, connected to the PWM generator and the H-bridge, and may be configured to detect an overcurrent passing through the H-bridge and to instruct the PWM generator to switch off a power supply to the H-bridge upon the detected overcurrent.

According to an embodiment, the medical device may further comprise at least one capacitor, arranged at a power supply side of the H-bridge and dimensioned to take an inrush current generated when switching on the power supply.

According to an embodiment, the coil may formed as a flat coil with at least one conductor wound spirally in a plane. This type of coil may also be referred to as planar-spiral type coil. In other words, the coil’s windings are not arranged side by side as in cylindrical coils, but one above the other. In this way, the coil may have a low inductivity, thereby further improving the broad-frequency magnetic field. Further, the coil may have a small volume, may be easy to be applied, a high rigidity due to the spiral structure, a minimized self-induction between the spirals, a self-resonance at high frequency, low parasitic capacity, and may be produced in a simple way.

In an embodiment, the coil may be mounted or printed on a printed circuit board, PCB. For example, the coil may be mounted in SMD technology or THT technology.

In an embodiment, the coil may have a time constant ts in the range of 5 ps to 15 ps, preferably in the range of 8 ps to 12 ps, further preferably of about 10 ps, and most preferably of 10,8 ps. For example, the time constant ts may be expressed by ts= -, wherein L is an inductivity of the coil and R is an internal resistivity of the coil. According to an embodiment, the coil may have an inductivity L in the range of 20 mH to 90 mH, preferably in the range of 40 mH to 80 mH, further preferably of 65 mH. In this way, the coil may have a low inductivity, thereby further improving the broad-frequency magnetic field.

In an embodiment, the coil may have a self-resonance frequency fir in the range of 4 MHz to 8 MHz, preferably in the range of 6 MHz to 7 MHz, further preferably of about 6,5 MHz, and most preferably of 6,525 MHz. The self-resonance of the coil may be understood as the frequency when a complex impedance is maximum, the phase between the voltage and current changes and a behavior of the coil turns form inductance to capacity.

According to an embodiment, the coil may have a resistivity R in the range of 2 W to 10 W, preferably in the range of 4 W to 8 W, further preferably in range of 5 W to 7 W, and most preferably of 6 W.

According to a second aspect, there is provided a medical system that comprises a number of medical devices according to the first aspect, wherein each one of the number of medical devices defines a dedicated channel of the medical system, and wherein each one of the number of channels is configured to provide one or more specific magnetic waveforms and/or intensities to a subject.

In this way, the effect to the subject can be multiplied according to the requirements of each application, i.e. for each control program and/or therapy and/or treatment program.

Preferably, each one of the number of medical devices is identical to the others. Further, each medical device may comprise its dedicated PWM generator, H-bridge and coil. The number of medical device may be one, two, three, four, five, six, seven, etc.

According to an embodiment, each one of the number of channels may be controlled independently from the others of the number of channels by a channel- specific part of the control program. In this way, different specific magnetic waveforms and/or intensities may be provided to the subject via the number of channels.

In an embodiment, the number of channels may be synchronized with each other, by aligning, for each channel, a number of time slots with each other, having a fixed minimum system resolution.

For example, the time slot of each channel may be defined or dimensioned with a length of time within which a reaction or response of the subject, i.e. the body or the substance, can be expected or even recognized, i.e. a reaction or response can be measured.

By way of example, the time slot may have a length of time in the range of Milliseconds (ms), but is not limited thereto. The synchronization may be performed at each time slot at the minimum system resolution.

A third aspect provides a method for operating a medical device, preferably the medical device of the first aspect and/or the medical system of the second aspect, for providing one or more specific magnetic waveforms and/or magnetic intensities, comprising: generating, by a pulse-width modulation, PWM, generator of a controller, a number of PWM signals based on a control program comprising information on the one or more specific magnetic waveforms and/or magnetic intensities to be provided; controlling, by the PWM generator, an H-bridge comprising a number of switches connected to the PWM generator to receive the number of PWM signals, by selectively switching on and off the number of switches, thereby generating an electric current, caused by the number of PWM signals, through the H-bridge; and driving a coil, connected to the number of switches, by the generated electric current, thereby generating, in response to the electric current, the one or more specific magnetic waveforms and/or magnetic intensities.

In this way, the medical device may provide a broad-frequency magnetic field. Further, this configuration allows a high power efficiency, a high frequency magnetic spectrum, and requires merely few electrical components.

According to an embodiment, the one or more specific magnetic waveforms and/or intensities may be applied to a subject for magnetic field treatment and/or magnetic field therapy.

In an embodiment, the control program may form a magnetic field treatment program and/or a magnetic field therapy program that may be applied to a subject. In other words, the magnet field generator may be used for magnetic field treatment and/or a magnetic field therapy.

According to an embodiment, the coil may forms an applicator coil and/or a therapy coil, to be applied on or around the subject to provide the one or more specific magnetic waveforms and/or intensities to the subject.

In an embodiment, the information on the one or more specific magnetic waveforms and/or magnetic intensities of the control program may comprise a sequence of signal indicators indicating whether one or more signal parameters, that may be used for generating the one or more specific magnetic waveforms and/or magnetic intensities to be provided, remain unchanged or are to be changed.

According to an embodiment, the one or more signal parameters may be selected from: a time slot duration indicating that the signal parameter remain unchanged during the time slot duration, an amplitude of the electric current, an offset of the electric current, a frequency of the electric current, a duty cycle if the waveform of the electric current is square, and a waveform type.

In an embodiment, wherein the waveform type may be selected from: sine, triangle, saw-tooth, square, DC, and pulse.

According to an embodiment, the method may further comprise deriving, from the control program, phase information and waveform information, deriving, from at least one look-up table, LUT, assigning the phase information and the waveform information to a specific waveform, a specific waveform, and generating, using the derived specific waveform, a source signal to be provided to the PWM generator.

In an embodiment, the method may further comprise utilizing a comparator, configured to compare a current phase information with a duty cycle value, for generating a specific square waveform for generating a source signal to be provided to the PWM generator.

According to a fourth aspect, there is provided a computer program element, which when executed by a processor is configured to carry out the method of the third aspect, and/or to control a device according to the first aspect, and/or to control a system according to the second aspect.

According to a fifth aspect, there is provided a computer-readable storage or transmission medium, which has stored or which carries the computer program element according to the fifth aspect.

It is noted that the above embodiments may be combined with each other irrespective of the aspect involved. Accordingly, the method may be combined with structural features of the device of the other aspects and, likewise, the devices of the first and/or third aspect may be combined with features of each other, and may also be combined with features described above with regard to the method according to the third aspect.

These and other aspects of the present invention will become apparent from and elucidated with reference to the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will be described in the following with reference to the drawings.

Fig. 1 shows in a schematic circuit diagram a medical device according to an embodiment.

Fig. 2 shows in a schematic circuit diagram a medical device according to an embodiment.

Fig. 3 shows in a schematic block diagram a signal generator of a medical device according to an embodiment.

Fig. 4 shows schematically an exemplary magnetic field generated by a medical device according to an embodiment.

Fig. 5 shows in a schematic block diagram a medical system comprising at least one medical device, according to an embodiment.

Fig. 6 shows two exemplary channels of a medical system according to an embodiment. Fig. 7 shows in a flow chart a method for operating a medical device and/or a medical system, according to an embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Fig. 1 shows in a schematic circuit diagram an exemplary embodiment of a medical device 100, which is configured to provide one or more specific magnetic waveforms and/or magnetic intensities.

The medical device 100 comprises a controller 110, which may be conceptually and/or functionally divided into one or more subunits, as indicated in the appended drawings by dashed rectangles. The controller 110 comprises a pulse-width modulation (PWM) generator 110-10 that is configured to generate a number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL corresponding to a control program comprising information on the one or more specific magnetic waveforms and/or magnetic intensities to be provided.

In other words, the medical device 100 is configured to provide a broad-frequency magnetic field. In this context, the control program may form a magnetic field treatment program and/or a magnetic field therapy program to be applied to the subject S.

Further, the medical device 100 comprises an H-bridge 120. comprising a number of switches 120-10, 120-20, 120-30, 120-40 which are connected to the controller 110, e.g. the PWM generator 110-10, to receive the number of PWM signals PWM LH, PWM LL,

PWM RH, PWM RL, wherein the number of switches 120-10, 120-20, 120-30, 120-40 is configured to be selectively switched on and off by the PWM generator 110-10 to generate an electric current, which are caused by the number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL, through the H-bridge 120.

Further, the magnetic field generator 100 comprises a coil 130, which is optionally arranged within the H-bridge 120 and connected to the number of switches 120-10, 120-20, 120-30, 120-40, and configured to be driven by the electric current and to generate, in response to the electric current, the one or more specific magnetic waveforms and/or magnetic intensities to be provided. Optionally, the medical device 100 may further comprise a number of switch drivers 120-11, 120-21, 120-31, 120-41, which are connected to the PWM generator 110-10, and which are configured to switch the corresponding switch 120-10, 120-20, 120-30, 120-40 on or off in accordance with the PWM signals PWM LH, PWM LL, PWM RH, PWM RL and/or the control program.

Optionally, the controller 110 may further comprise a signal generator 110-20, which is arranged upstream to and connected to the PWM generator 110-10. It is configured to generate, based on the control program, a source signal, corresponding to the specific magnetic waveforms and/or magnetic intensities to be provided, to be used by the PWM generator 110-20 to generate the number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL.

Fig. 2 shows in a schematic circuit diagram the medical device 100 according to an exemplary embodiment. Deviating from the embodiment shown in Fig. 1, here the medical device 100 further comprises a detection circuit 140, which is connected to the PWM generator 110-10 and the H-bridge 120. The detection circuit 140 may be implemented in hardware and/or software and may be configured to detect an overcurrent passing through the H-bridge 120. Further, the detection circuit 140 may be configured to instruct the PWM generator 110-10 to switch off a power supply to the H-bridge 120 upon the detected overcurrent. Such an overcurrent may occur if the PWM signals PWM LH, PWM LL,

PWM RH, PWM RL do not comply with a time constant of the coil 130. In particular, if the PWM signals PWM LH, PWM LL, PWM RH, PWM RL are generated, an overcurrent may occur if a PWM duty-cycle ratio does not comply with the time constant of the coil 130, and the current passing through the coil 130 reaches a non-allowed high value. This overcurrent error may be detected by the detection circuit 140, and the PWM generator 110- 10 receives a stop signal, e.g. a Pwr OFF signal, to power off the H-bridge 120. Further, such an overcurrent may occur if the PWM generator 110-10 stops to provide PWM LH,

PWM LL, PWM RH, PWM RL, by which the coil 130 arrives in a saturation mode. In this case, the detection circuit 140 may send a stop signal, e.g. a Pwr OFF signal, to power off the H-bridge 120.

Further, in at least some embodiments, the medical device 100 may comprise a power switch 150, which is connected to the detection circuit 140 and a power supply 160.

The power supply 160 is configured to power the H-bridge 120. The power switch 150, which may be implemented as an electronic switch, may be connected and/or configured to be selectively switched on and off by a respective signal received by the PWM generator 110-10. For example, as indicated by a signal designated as Pwr_ON/OFF signal, the PWM generator 110-10 may be configured to power on or off the power switch 150 by instructions derived from the control program and/or upon an instruction received by the detection circuit 140.

Further, in at least some embodiments, the medical device 100, and particularly the H-bridge 120, may comprise at least one capacitor 170, which is connected, e.g. via the detection circuit 140 and/or the power switch 150, to the power supply 160. The capacitor 170 may be dimensioned to take an inrush current generated when switching on the power supply 160.

Now referring to Fig. 3, which shows a schematic block diagram, the signal generator 110-20 is described in more detail. It may be arranged upstream to and connected to the PWM generator 110-10, and may be configured to generate, based on the control program, a source signal that corresponds to the specific magnetic waveforms and/or magnetic intensities to be provided, to be used by the PWM generator 110-10. Based on the source signal, the PWM generator may generate the number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL.

According to Fig. 3, the signal generator 110-20 may comprise several subunits, such as a waveform generator unit 110-21, a phase generator unit 110-22, a duty cycle variation unit 110-23, an amplitude variation unit 110-24, an offset variation unit 110-25, a frequency compensation unit 110-26, and an adder 110-27. Thereby, the signal generator 110-20 may be implemented in hardware and/or software. The output of the signal generator 110-20 may be the source signal, which may be the output of the adder 110-27, which source signal may then be provided to the PWM generator 110-10. The source signal may also be referred to as a sample.

The waveform generator unit 110-21 may be used to generate the required waveforms in a normalized form, i.e. by providing a value between -1 to +1, which may be provided as a bitstream. For example, the waveform generator 110-21 may receive one or more input signals, such as a clock signal, a phase information, used to access one or more look-up tables (LUT) containing waveform data, a duty cycle information, and a waveform information. Thereby, the one or more specific waveforms may be generated utilizing the one or more LUT's, comprising predefined data or user defined data, e.g. for providing advanced waveforms. Further, a specific square waveform may be generated utilizing a comparator which compares a current phase value with a duty cycle value.

The phase generator unit 110-22 may be configured to generate a phase information for the waveform generator 110-21 according to a frequency information, received as an input. For example, the phase generator unit 110-22 may receive one or more input signals, such as a clock signal, a reset signal a variation mode information, such as no variation, linear, exponential, and logarithmic, a frequency information, and a variation step.

The duty cycle variation unit 110-23, the amplitude variation unit 110-24, and the offset variation unit 110-25 may also be summarized and referred to as a parameter variation unit, configured to generate a variation of one or more parameters including an amplitude, frequency, Offset and Duty cycle for a given Time Slot duration of the source signal. The duty cycle variation unit 110-23, the amplitude variation unit 110-24, and the offset variation unit 110-25, i.e. the parameter variation unit, are configured to receive one or more input signals, such as a clock signal, a variation step, and a variation type. The output signal of the duty cycle variation unit 110-23, the amplitude variation unit 110-24, and the offset variation unit 110-25, i.e. the parameter variation unit, is a normalized variation, which may then be provided to the phase generator unit 110-22.

The frequency compensation unit 110-26 may be configured to adjust an amplitude of the generated signal, namely the signal generated by the phase generator unit 110-22, according to the current frequency value to compensate a variation of an impedance of the coil 130 with frequency.

Fig. 4 shows schematically an exemplary magnetic field generated by the medical device 100 as described herein. As can be seen, the magnetic field is emit by the coil 130, which is preferably arranged in a plane.

Fig. 5 shows in a schematic block diagram a medical system 200, which is configured to apply the one or more specific magnetic waveforms and/or intensities to a subject S for magnetic field treatment and/or magnetic field therapy and/or diagnosis.

The medical system 200 comprises at least one medical device 100 as described above. By way of example, the medical device 200 comprises a number of medical devices 100, each of which forms a dedicated channel of the medical system 200. The number of channels, i.e. the number of medical devices 200, may be one, two, three, four, five, six, seven, eight, nine, or more. It is noted that each medical device 100, i.e. each channel of the medical system 200, may comprise its own dedicated PWM generator 110-10. In at least some embodiments, each medical device 100, i.e. each channel of the medical system 200, may further comprise its own dedicated signal generator 110-20. Accordingly, the medical system 200 may comprise a number of signal-generators 110-20 corresponding to the number of channels. Alternatively, it is the medical system 200 may comprise merely one signal generator 110-20 connected to each one of the number of PWM generators 110-10.

The controller 110 (see Fig. 1 and 2) may be configured to control each one of the number of channels independently from the others of the number of channels by a channel- specific part of the control program. Alternatively, a number of control programs may be provided, i.e. one dedicated control program for each channel, wherein the number of control programs may correspond to the number of channels.

Further, the controller 110 may be configured to synchronize the number of channels with each other, by aligning, for each channel, a number of time slots 110-30 (see Fig. 6) with each other, having a fixed minimum system resolution. For example, such a time slot may have a length in the millisecond (ms) range, e.g. 1 ms, 2 ms, 3 ms, etc., wherein advance or delayed time slots be aligned with each other, e.g. by providing a waiting period for one or more of the channel-specific time slot, delaying a channel-specific time slot with respect to the other channels, etc.

Fig. 6 shows for the medical system 200 of Fig. 5 an exemplary data flow of two exemplary ones of the number of channels, i.e. two exemplary ones of the number of medical devices 100. It should be noted that the principle shown in Fig. 6 may be applied to any other number of channels. As shown, each channel is clocked by the above-mentioned number of time slots 200-10 at the minimum system resolution. As shown in Fig. 6 by arrows between the time slots of each channel, the channels of the medical system 200 may be synchronized with each other by aligning the corresponding time slots with each other.

Further, Fig. 6 shows for each channel exemplary sequences of signal indicators 200- 20, which may also be referred to as information on the one or more specific magnetic waveforms and/or magnetic intensities of the control program. Each signal indicator 200-20 indicates, to be considered for generating the source signal and/or the PWM signal PWM LH, PWM LL, PWM RH, PWM RL, whether one or more signal parameters, used to generate the one or more specific magnetic waveforms and/or magnetic intensities to be provided, remain unchanged or are to be changed. For example, the signal parameters may be set at an initial starting point of the control program, and may then be changed or remain unchanged. As indicated in Fig. 6 by rectangles of corresponding length, the minimum time duration of each signal indicator 200-20 corresponds to the length of the above time slot, i.e. the minimum system resolution.

Optionally, the one or more signal parameters may be selected from: a time slot duration indicating that the signal parameter remain unchanged during the time slot duration, an amplitude of the electric current, an offset of the electric current, a frequency of the electric current, a duty cycle if the waveform of the electric current is square, and a waveform type.

Optionally, the waveform type may be selected from: sine, triangle, saw-tooth, square, DC, and pulse.

Optionally, the H-B ridge 120 and the coil 130 may form an integral, i.e. one-piece, applicator that is configured to be applied on or around the subject S to provide the one or more specific magnetic waveforms and/or intensities to the subject S. Therefore, the coil 130 may also be referred to as or may form an applicator coil and/or a therapy coil, configured to be applied on or around the subject S to provide the one or more specific magnetic waveforms and/or intensities to the subject S.

Fig. 7 shows in a flow chart a method for operating the above medical device 100 according to one or more of the exemplary embodiments described above.

In a step SI, the PWM, generator 110-10 generates a number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL based on the control program comprising information on the one or more specific magnetic waveforms and/or magnetic intensities to be provided.

In a step S2, the PWM generator 110-10 controls the H-bridge 120 comprising the number of switches 120-10, 120-20, 120-30, 120-40 connected to the PWM generator 110-10 to receive the number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL, by selectively switching on and off the number of switches 120-10, 120-20, 120-30, 120-40, thereby generating an electric current, caused by the number of PWM signals PWM LH, PWM LL, PWM RH, PWM RL, through the H-bridge 120.

In a step S3, the coil 130, connected to the number of switches 120-10, 120-20, 120- 30, 120-40, is driven by the generated electric current, thereby generating, in response to the electric current, the one or more specific magnetic waveforms and/or magnetic intensities.

Optionally, the one or more specific magnetic waveforms and/or intensities may be applied to the subject S for magnetic field treatment and/or magnetic field therapy.

Optionally, the control program may form a magnetic field treatment program and/or a magnetic field therapy program that is applied to the subject S.

Optionally, the coil 130 may form an applicator coil and/or a therapy coil, to be applied on or around the subject S to provide the one or more specific magnetic waveforms and/or intensities to the subject S.

Optionally, the method may further comprise deriving, from the control program, phase information and waveform information, deriving, from the at least one look-up table, LUT, assigning the phase information and the waveform information to a specific waveform, a specific waveform, and generating, using the derived specific waveform, a source signal to be provided to the PWM generator 110-10.

Optionally, the method may further comprise utilizing a comparator, configured to compare a current phase information with a duty cycle value, for generating a specific square waveform for generating a source signal to be provided to the PWM generator 110-10.

In another exemplary embodiment, a computer program or computer program element is provided that is characterized by being configured to execute the method steps of the method according to one of the preceding embodiments, on an appropriate system.

The computer program element might therefore be stored on the controller, e.g. a data processing unit, which might also be part of an embodiment. This data processing unit may be configured to perform or induce performing of the steps of the method described above. Moreover, it may be configured to operate the components of the above described device and/or system. The computing unit can be configured to operate automatically and/or to execute the orders of a user. A computer program may be loaded into a working memory of a data processor. The data processor may thus be equipped to carry out the method according to one of the preceding embodiments.

Further, the computer program element might be able to provide all necessary steps to fulfill the procedure of an exemplary embodiment of the method as described above.

According to a further exemplary embodiment of the present invention, a computer readable medium, such as a CD-ROM, USB stick or the like, is presented wherein the computer readable medium has a computer program element stored on it which computer program element is described by the preceding section.

A computer program may be stored and/or distributed on a suitable medium, such as an optical storage medium or a solid state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the internet or other wired or wireless telecommunication systems.

However, the computer program may also be presented over a network like the World Wide Web and can be downloaded into the working memory of a data processor from such a network. According to a further exemplary embodiment of the present invention, a medium for making a computer program element available for downloading is provided, which computer program element is arranged to perform a method according to one of the previously described embodiments of the invention.