WO2024127242A1

WO2024127242A1 - A pulsed electromagnetic field apparatus and method for generating frequencies

Info

Publication number: WO2024127242A1
Application number: PCT/IB2023/062533
Authority: WO
Inventors: Dragutin KUSTRIMOVIC
Original assignee: Teslab Llc
Priority date: 2022-12-16
Filing date: 2023-12-12
Publication date: 2024-06-20
Also published as: GB2625372A; GB202219046D0

Abstract

A pulsed electromagnetic field (PEMF) apparatus is provided for use in PEMF treatment and therapies. The apparatus comprises a pulse generator configured to generate a pulsed electrical signal, an electromagnetic field generation means configured to generate a pulsed electromagnetic field based on the pulsed electrical signal from the pulse generator, and a non-transitory computer readable storage medium comprising non- transitory instructions configured to cause apparatus to generate a pulsed electromagnetic field comprising (i) a modified sawtooth waveform having a pre-stress period, or (ii) a quasi-sine signal modulated by a square waveform using pulse width modulation. A PEMF apparatus and method are also provided for maintaining frequency stability of a PEMF apparatus, in which an indication of time is obtained from an internal system clock of the pulsed electromagnetic field device and from a second clock external to the pulsed electromagnetic field device, the indications of time from each are then compared, and a feedback circuit of the pulsed electromagnetic field device is subsequently adjusted based on the comparison of the indication of time from the internal system clock and the indication of time from the reference clock.

Description

A pulsed electromagnetic field apparatus and method for generating frequencies

Field of the invention

The present disclosure relates to pulsed electromagnetic field devices, in particular for application of pulsed electromagnetic fields onto bodily tissue for regenerative and restorative effects, and for disabling pathogens, such as bacteria, viruses, and parasites.

Background

Pulsed electromagnetic field (PEMF) therapy is a type of electromagnetic therapy that uses pulsed electromagnetic fields to achieve increased regeneration and/or restitution effects at a cellular level in animals and humans. PEMF therapy can also be used to disable pathogens

PEMF therapy often finds use as an adjuvant treatment for various human diseases or trauma, including but not limited to, bone fractures, arthritis and osteoarthritis, acute inflammation, chronic inflammation, cancers, edema, pain, chronic pains, wounds, and chronic wounds. To date, PEMF therapy has received FDA approval for healing of bone fractures, treatment of urinary incontinence, muscle stimulation, cervical fusion surgery, treatment of depression and anxiety, and treatment of brain cancer.

However, sudden uncontrolled increases and fluctuations in electromagnetic field can irritate cells, causing immediate stress and resonant side effects. This is a particular problem with square wave PEMF signals widely used in conventional PEMF devices. Furthermore, the frequency =the electromagnetic field generated by conventional PEMF devices is often unstable and the strength of the frequency is inadequate. The precision of frequency generated is also often imprecise which can result in sub-optimal therapies and treatments, and even damage to cells.

Furthermore, tolerance errors and component aging can cause frequency drift within conventional PEMF devices. This again reduces the precision of the therapeutic frequencies generated, thereby reducing the effectiveness and the precision of the therapy or treatment. Summary of the invention

Aspects of the invention are as set out in the independent claims and optional features are set out in the dependent claims. Aspects of the invention may be provided in conjunction with each other and features of one aspect may be applied to other aspects.

In a first aspect of the invention, there is provided a pulsed electromagnetic field apparatus comprising a pulse generator configured to generate a pulsed electric signal, and an electromagnetic field generation means configured to generate a pulsed electromagnetic field based on the pulsed electric signal from the pulse generator. The pulsed electromagnetic field apparatus further comprises a non-transitory computer readable storage medium comprising non-transitory instructions configured to cause the pulse generator to generate a pulsed electric signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field comprising a modified sawtooth waveform comprising a pre-stress period. This may be advantageous because the pre-stress period can provide an adjustment period for cells or medium to adjust to the increase in magnetic field, mitigating against immediate stress and resonant side effects that can be caused a result of exposing cells to sudden increases in magnetic field.

Each ramp of the modified sawtooth waveform may comprise an inflection point, such that a portion of the ramp prior to the inflection point defines a pre-stress period. The inflection point may be advantageous to provide a small pause in the rate of increase in the magnetic field in order for the cells or medium to acclimatise, before the magnetic field is again increased.

The non-transitory instructions may be configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F(t) = (sin(5 11 IT - 0.02))^1/kt, where t = time (normalized 0 < t < 1); and k = form factor (k > 1). This waveform may be particularly advantageous to powerfully recharge targeted body tissues or organs through targeted treatment or therapy.

In some examples, the non-transitory instructions may be configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F(t) = 1 + (1 + 4t (t-k))(t-1), where t = time (normalized 0 < t < 1); k = form factor (0.25 < k < 0.75). This waveform may be particularly advantageous to regenerate more cells quickly and more intensively than conventional PEMF therapies.

Alternatively, or in addition, the non-transitory instructions may be configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with a pre-stress period function of 0.5(sin(1 Ot I TT))^1/‘ for 0 < t < 0.5 normalized; and 0.5 + 0.5(sin (5t/Tr + /8))^1/10‘ for 0.5 < t < 1 normalized. This may be advantageous to provide a smooth way to recharge cells, avoiding resonance side effects and reducing cell irritation.

The non-transitory instructions may also be configured to cause the pulse generator to generate a pulsed electric signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field comprising a modified sawtooth waveform comprising a relaxation period. This may be advantageous to provide a relaxation period for cells or medium following the application of the magnetic field, again mitigating against immediate stress and resonant side effects that can be caused a result of repeatedly exposing cells to sudden increases in magnetic field. For example, the non- transitory instructions may be configured to cause the modified sawtooth waveform to comprise a period of minimum field between each ramp and each cliff of adjacent periodic sawtooth waveforms, such that the period of minimum field after each cliff defines a relaxation period.

In some examples, the non-transitory computer readable storage medium may comprise non-transitory instructions configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F(... t^m - tⁿ + t + t^1/q - t^1/p... ), where t is time. This waveform may be particularly advantageous for targeted treatments, for example targeted to recharge specific tissues or organs. Variables m, n, q, and p are natural numbers, preferably positive natural integers, and their selection may define the envelope of signal. They may be experimentally determined or determined by the method of numerical analysis. Some terms of series in the function's argument may be omitted. In general, m = n+1 , i.e. p=k+1 , for example: B = k ( t⁵ - 1² + t^1/2 ) + p where: t = time (normalized from 0 to 1 ) k = 0.25 and p = 0 ... for 0 < t < 0.5 k = 1.75 and p = 0.1221 ... for 0.5 < t < 1.

The non-transitory computer readable storage medium may comprise a set of multiple non- transitory instructions, wherein the each of the set of non-transitory instructions corresponds to different non-transitory instructions configured to cause the pulse generator to generate a different pulsed electrical signal and therefore generate a different pulsed electromagnetic field. In some examples, the set of instructions may comprise at least: (i) non-transitory instructions configured to cause the pulse generator to generate a pulsed electrical signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field having a function of F{t²⁽ⁿ⁺¹⁾-t²ⁿ+t²⁽ⁿ’¹⁾... +t}; and (ii) non-transitory instructions configured to cause the pulse generator to generate a pulsed electrical signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field having a function of F{...t^m - tⁿ + t + t^1/q - t^1/p...}. The skilled person will understand that some terms in series of the function's argument may be omitted.

In another aspect of the invention there is provided a pulsed electromagnetic field apparatus comprising a pulse generator configured to generate a pulsed electric signal and an electromagnetic field generation means, wherein the electromagnetic field generation means is configured to generate a pulsed electromagnetic field based on the pulsed electric signal from the pulse generator. The apparatus further comprises a non- transitory computer readable storage medium comprising non-transitory instructions configured to cause the pulse generator to modulate a quasi-sine signal by a square waveform. This waveform may be particularly advantageous for destructive use, for example as used to disable pathogens.

The non-transitory instructions may be configured to cause the pulse generator to modulate a quasi-sine signal by a square waveform using pulse width modulation. The pulse width modulation may be advantageous to enable the resulting pulsed electromagnetic field to cover a richer spectrum of harmonics which can be used as therapy.

The non-transitory computer readable storage medium may comprise a set of non- transitory instructions, wherein the set of non-transitory instructions also comprises the non-transitory instructions as defined in the previous aspect of the invention.

In another aspect of the invention, there is provided a pulsed electromagnetic field apparatus comprising a pulse generator configured to generate a pulsed electric current having a frequency, and an electromagnetic field generation means, wherein the electromagnetic field generation means is configured to generate a pulsed electromagnetic field based on the pulsed electric current from the pulse generator. The apparatus also comprises an internal system clock, wherein the frequency of the pulsed electric current is configured to be based on the internal system clock and a wireless communication interface configured to obtain an indication of time from an external reference clock, for example, but not limited to, via the internet. The apparatus further comprises a feedback circuit configured to adjust the internal system clock based on the obtained indication of time from the external reference clock. This may be advantageous to maintain frequency stability, accuracy, and precision by correcting for internal clock errors or drift, for example caused by tolerances within the apparatus, component ageing, and/or external and environmental conditions. Frequency stability, accuracy, and precision are essential for providing effective PEMF therapies and treatments throughout the lifetime of the apparatus to precisely target the desired medium (e.g., pathogen or human cell). This apparatus may enable precision of the programmed frequencies to be controlled up to at least two decimal places.

The feedback circuit may be a phase locked loop (PLL). This may be advantageous to adjust the internal system clock based on the obtained indication of time from the external reference clock such that the phases are matched.

The external reference clock may be a Coordinated Universal Time (UTC) clock, such as a Unix Epoch clock. This may be advantageous to provide a reliable time standard.

The internal system clock, otherwise known as the Real Time Clock (RTC), may comprise a crystal oscillator, preferably wherein the crystal oscillator has a stability of <20 parts per million, ppm. This may be advantageous to minimise tolerances and drift within the apparatus, increasing stability.

Furthermore, the internal system clock may use the same crystal oscillator as used to generate the frequency of the pulsed electric current, for example the crystal oscillator of the pulse generator. This may also be advantageous to minimise tolerances and movements within the apparatus, as well as increasing the stability of the frequency of the apparatus, because only one crystal oscillator is used.

The wireless communications interface may be configured for at least one of a Bluetooth™, 3G, 4G, 5G, and/or Wi-Fi communication.

Referring now to any of the aforementioned aspects of the invention, the electromagnetic field generation means may comprise a coil assembly.

The pulse generator may further comprise a signal reactor configured to generate digital pulsed electrical signals, and an amplifier configured to convert the digital pulsed electrical signals from the signal reactor into analog pulsed electrical signals. The signal reactor may be configured to generate the digital pulsed electrical signals by modulating a carrier frequency by a therapeutic frequency, wherein the carrier frequency is a harmonic of the therapeutic frequency. This may be advantageous to avoid use of a fixed and constant parasitic carrier frequency which collides with the therapeutic frequency.

For example, the signal reactor may be configured to provide a PWM (Pulse Wide Modulated) signal, while the conversion of this signal to analog is performed in the output amplifier.

The carrier frequency of the PWM signal from the signal reactor is the n^th harmonic of the therapeutic frequency, where "n" is a positive natural number. Preferably, the value of “n” is significantly higher than the therapeutic frequency, for example wherein n is at least 10, for example 11 , 13, 16, etc.

The step of PWM modulation increase is the m^th harmonic of the therapeutic frequency. Where "m" is a natural number such that m = k * n, where "k" is also a natural positive integer. This means that the maximum fundamental parasitic frequency that occurs in the amplifier, during the conversion of the digital signal to analog, is the significantly higher m^th harmonic of the therapeutic frequency (121^st, 169^th, etc.). This can even be part of the therapy. Other, higher parasitic frequency components of the signal will be primarily neutralized by the mode of operation of the AB-D output amplifiers, as well as by the inductive nature of the antenna, and will be at the noise level.

Depending on the application, the harmonic of the carrier frequency can be adjusted, for example the carrier frequency can be the 11th, 13th, or e.g. 169th harmonic. In this way, the carrier frequency is part of the treatment and does not interfere with the therapy by some unwanted fixed frequency effect.

The amplifier is configured to perform the digital to analog conversion using discrete output power transistors. This may be advantageous to avoid the amplifier itself from having a fixed parasitic carrier frequency. The amplifier may be a hybrid AB-D class amplifier. The class AB-D output amplifier may be advantageous to provide a quality output signal with high efficiency, with low distortion and parasitic harmonics. This may be achieved as, after the AB-D amplifier, there may be no additional large inductive filters at critical frequencies. As such, the signal is sent directly to the electromagnetic field generation means - which may be inductive in nature at critical frequencies and may act as a filter itself. Synchronous operation of AB-D amplifiers ensures that the fundamental, carrier and parasitic frequencies are in the ratio of natural numbers (or harmonics). Parasitic harmonics may then be part of the treatment.

The pulsed electromagnetic field (PEMF) apparatus may further comprise a sensor configured to measure the output electromagnetic field, and a feedback loop configured to monitor the electromagnetic field detected by the sensor and control the operation of the pulse generator based on the output electromagnetic field. This may be advantageous as the feedback loop may adjust the operation of the apparatus if some of the parameters sensed by the sensor are out of the desired operational limits. This can ensure the quality of the output signal.

The electromagnetic field generation means may further comprise a bifilar antenna configured to generate scalar waves. This may be advantageous to minimise electromagnetic radiation, reducing the induction, and transmitting the signal in its original form as the signal is not transformed as it happens in conventional solutions. This is because the inductance of the antenna is reduced to a minimum. The bifilar antenna is configured to emit a pair of electromagnetic fields in opposite directions which cancel each other and create a scalar field. This applies only if the state of resonance is accomplished, which requires the same waveform, the same frequency, and the opposite phase. This condition is also a prerequisite for a full energy transfer, which cannot be represented by the Hertzian waves because of the energy decrease with the square of the separation distance.

The pulsed electromagnetic field apparatus may further comprise a wireless communications interface configured to communicate with a remote device. The wireless communications interface may be configured to control the operation of the pulse generator, for example wherein the operation of the pulse generator may be remotely controlled by a remote device, for example via an app. The wireless communications interface may, alternatively or in addition, be configured to obtain additional non-transitory instructions configured to cause the pulse generator to generate a pulsed electric current which in turn causes the electromagnetic field generation means to generate a different pulsed electromagnetic field comprising a different modified waveform, for example where additional sets of frequency programmes or updates can be downloaded from a remote server. The wireless communications interface may be configured for at least one of a Bluetooth™, 3G, 4G, 5G, and/or Wi-Fi communication.

The pulsed electromagnetic field apparatus may further comprise a linear power supply, or alternatively be configured to receive power from a linear power supply. This may be advantageous such that power supply and voltage stabilization can be done without switching regulators to avoid interference and parasitic frequencies to the output PEMF signal.

The pulsed electromagnetic field apparatus may further comprise a first electromagnetic field generation means, and a second electromagnetic field generation means. Each electromagnetic field generation means is configured to generate a pulsed electromagnetic field having a frequency, wherein the two electromagnetic field generation means are configured such that the frequency of the PEMF signal of the first electromagnetic field generation means is out of phase with the frequency of the PEMF signal of the second electromagnetic field generation means. This may be advantageous to reduce the time and improve efficiency of a PEMF treatment. Use of two electromagnetic field generation means may also improve the efficiency of pathogen destruction compared to a single electromagnetic field generation means.

In addition, or instead of, the frequencies of the PEMF signal of the first and second electromagnetic field generation means being out of phase, the PEMF signal of the first electromagnetic field generation means and the PEMF signal of the second electromagnetic field generation means may have different frequencies. For example wherein the PEMF signal ofthe first electromagnetic field generation means and the PEMF signal of the second electromagnetic field generation means less than 2 Hz apart. In some examples, the PEMF signal of the first electromagnetic field generation means and the PEMF signal of the second electromagnetic field generation means are configured to be a fraction of a Hz apart.

The first and second electromagnetic field generation means may be synchronised and controlled simultaneously to ensure that the resulting PEMF fields are out of phase. In some examples, the first and second electromagnetic field generation means are synchronised and controlled by a remote device, for example via a wireless communications interface. The PEMF apparatus of the present invention aims to achieve professional grade performance with consumer electronics usability, thanks to the aforementioned features.

In another aspect of the invention there is provided a method for maintaining frequency stability of a pulsed electromagnetic field device. The method comprises obtaining an indication of time from an internal system clock of the pulsed electromagnetic field device and obtaining an indication of time from a second clock, external to the pulsed electromagnetic field device. The method then compares the indication of time from the internal system clock to the indication of time from the second clock and adjusts a feedback circuit of the pulsed electromagnetic field device based on the comparison of the indication of time from the internal system clock and the indication of time from the external reference clock. This may be advantageous to provide and maintain frequency stability and precision by correcting for frequency errors or drift within the apparatus, for example caused by tolerances within the apparatus, component ageing, and/or external conditions. Frequency stability and precision is essential for providing effective PEMF therapies and treatments throughout the lifetime of the apparatus.

Adjusting the feedback circuit may comprise adjusting a phase locked loop (PLL). This may be advantageous to adjust the internal system clock based on the obtained indication of time from the external reference clock such that the phase and/or frequency are matched.

The indication of time from the second clock may be obtained from a Coordinated Universal Time (UTC) clock, such as a Unix Epoch clock. This may be advantageous to provide a reliable time standard for frequency accuracy adjustment.

In another aspect of the invention, there is provided a computer readable non-transitory storage medium comprising a program for a computer configured to cause a processor to perform the method for maintaining frequency stability and precision of a pulsed electromagnetic field device, as defined in the previous aspect of the invention.

In another aspect of the invention, there is provided a method for stimulating regeneration or recharging of cells comprising applying a pulsed electromagnetic field to a desired area of cells, wherein the pulsed electromagnetic field comprises a modified sawtooth waveform comprising a pre-stress period.

Each ramp of the modified sawtooth waveform may comprise an inflection point, such that a portion of the ramp prior to the inflection point defines a pre-stress period.

The modified sawtooth waveform may further comprise a relaxation period. For example, wherein the modified sawtooth waveform may comprise a period of minimum field between each ramp and each cliff of adjacent periodic sawtooth waveforms, such that the period of minimum field after each cliff defines a relaxation period.

The waveform may have the function F{...t^m - tⁿ + t + t^1/q - t^1/p... }, where t is time. In some examples, the waveform may have the function F(t⁴-t²+t), where t is time.

Drawings

Embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1A shows an isometric view of an example pulsed electromagnetic field (PEMF) device.

Fig. 1 B shows a plan view of the PEMF device of Fig. 1A, including detailing internal features.

Fig. 2 shows a block diagram of the components of a PEMF apparatus, for example the PEMF device of Figs. 1 A-1 B.

Fig. 3 shows a first example waveform suitable for PEMF therapy or treatment, wherein the waveform is configured to be generated by a PEMF apparatus, for example the PEMF device of Figs. 1A-2. Fig. 4 shows a second example waveform suitable for PEMF therapy or treatment, wherein the waveform is configured to be generated by a PEMF apparatus, for example the PEMF device of Figs. 1A-2.

Fig. 5 shows a third example waveform suitable for PEMF therapy or treatment, wherein the waveform is configured to be generated by a PEMF apparatus, for example the PEMF device of Figs. 1A-2.

Figs. 6A and 6B show a fourth example waveform suitable for PEMF therapy or treatment, wherein the waveform is configured to be generated by a PEMF apparatus, for example the PEMF device of Figs. 1A-2.

Fig. 6C shows an example waveform applied to the long-term control of a signal envelope suitable for PEMF therapy or treatment, wherein the waveform is configured to be generated by a PEMF apparatus, for example the PEMF device of Figs. 1A-2.

Fig. 7 shows a method for maintaining frequency stability of a PEMF apparatus, for example the PEMF device of Figs. 1A-2.

Fig. 8A-8B shows another embodiment of a PEMF apparatus, comprising a pulse generation device shown in Fig. 8A, for use with an external electromagnetic field generation device shown in Fig. 8B. Fig. 8C shows an alternative embodiment of an external electromagnetic field generation device to that shown in Fig. 8B.

Fig. 9A shows another embodiment of a PEMF apparatus, including the internal components of such. Fig. 9B shows a plan view of the PEMF apparatus of Fig. 9A.

Fig. 10A shows a plan view, including internal components, of another embodiment of a pulse generation device for use in a PEMF apparatus. Fig. 10B shows front and back isometric views of the device of Fig. 10A.

Fig. 10C shows another embodiment of an external electromagnetic field generation device, in this case an electromagnetic field generation belt.

Specific description

Embodiments of the claims relate to PEMF apparatus, and methods of operation.

Fig. 1A shows an example PEMF device 100 comprising a housing 102. In this example, the housing has a square cross-section, however the skilled person will understand that housings of other shapes and configurations may be used, for example as shown in more detail in Fig. 9.

The exterior of the housing 102 comprises a plurality of buttons 104, in this case two buttons. The buttons 104 are configured to receive user input in order to control operation of the PEMF device 100.

The exterior of the housing 102 also comprises a display 106. The display 106 is configured to display operational parameters of the device 100, and/or device status.

The housing 102 further comprises a power input 108. The power input 108 is configured to receive a linear power supply unit (not shown).

Fig. 2 shows a block diagram illustrating the components within the housing 102 of a PEMF device 100. The device 100 comprises a processor 202 coupled to a signal reactor 204.

The device 100 further comprises an amplifier 206 electrically coupled to the signal reactor 204. In this example, the amplifier 206 is an AB-D class discrete output amplifier.

The device 100 further comprises an electromagnetic field generation means (not shown) which in this case is a coil.

The device 100 also comprises a memory 210 and a wireless communications interface 208, both electrically coupled to the controller 202. The memory 210 is configured to store non-transitory instructions configured to cause the pulse generator (comprising the signal reactor 204 and amplifier 206) to generate a pulsed electrical signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field. The memory 210 is preferably configured to store a set of different non-transitory instructions, each corresponding to a different therapeutic or treatment program associated with the generation of a different pulsed electrical signal, and thus a different pulsed electromagnetic field.

The wireless communications interface 208 is configured to control the operation of the device 100, for example wherein the operation of the processor 202, and hence signal reactor 204, may be remotely controlled by a remote device, for example via an app.

Optionally, the wireless communications interface 208 may also be electrically coupled to the memory 210 such that the wireless communications interface 208 is configured to obtain additional non-transitory instructions which may be downloaded to the memory 210, wherein additional non-transitory instructions correspond to different therapeutic or treatment programs associated with the generation of a different pulsed electrical signal, and thus a different pulsed electromagnetic field, enabling additional sets of frequency programmes or updates can be downloaded from a remote server. The wireless communications interface 208 in this example comprises a Bluetooth™ module, however the skilled person will understand that other interfaces can be used.

The device 100 also comprises at least one sensor 212. The sensor(s) 212 is configured to measure at least one operational parameter of the device 100, including but not limited to operational voltage, current, or frequency. In this example, the sensor 212 is a small loop antenna configured to monitor the output signal.

The processor 202 is configured to generate command signals to control operation of the signal reactor 204.

The signal reactor 204 is configured to generate in real time the digital signals required for digital-to-analog (DA) conversion by the output amplifier 206. The signal reactor 204 is configured to modify parameters of the digital signals to control the output signal both on the short term, and the long term. Short term control refers to the shape of the envelope signal (such as square, sawtooth, or special functions calculated envelope), whereas long term control refers to frequency change in set time intervals - linear or discontinuous, as well as phase, polarity, modulation, power, etc.

In addition to generating the digital signals needed to drive the inputs of output amplifier 206, the signal reactor 204 is also configured to generate an analog signal envelope for error correction in the hybrid AB-D amplifier 206.

The amplifier 206 is configured to perform DA conversion of the digital signal received from the signal reactor 204. The amplifier 206 is configured to perform the DA conversion in discrete output transistors to avoid having a fixed parasitic carrier frequency. The amplifier 206 is also configured to output the signal as a differential output signal, this may be advantageous to simplify the power supply of the device 100 itself and can reduce parasitic interference on the output signal.

In this specific example, all electronic components are located on a printed circuit board (PCB) 110 to improve reliability during assembly and reduce failure rate. The PCB 110 is preferably a minimum four-layer PCB made using standard FR4 material with a copper (Cu) layer of 35 microns depth. The thickness of the PCB, and the distance between the top and bottom layers is 1.6 mm. This is configured to minimize the parasitic capacitances between the layers which can affect the envelope and propagation of the signal.

There are no large areas of copper ground (GND) and power supply layers on the printed circuit board 110, except where necessary for soldering components. This results in a significant Cu area reduction at the PCB 110. The degree of integration is also high. Components are densely distributed to reduce the surface areas of copper ground and power supply layers. In this way, the losses caused by induction are reduced to facilitate ideal form of radiation field in all directions.

Circuits, pairs of incoming and outgoing currents, which pass through the same node, are placed oppositely on the printed circuit board 110. This reduces the gradient of the electromagnetic field and neutralizes induced parasitic induction currents. In critical places, additional blockages are made with by-pass capacitors for the same reason.

In use, a user may select, using the input buttons 104, a program from a set of pre-set or loaded programs stored in the device's memory 210. Based on stored instructions of the selected program, the processor 202 generates command signals that it forwards to the signal reactor 204. In response, the signal reactor 204 generates digital signals in real time. The digital signals are subsequently converted into analog signals by the output amplifier 206. The signal output by the amplifier 206 is of differential type. This signal is then forwarded to the electromagnetic field generation means which generates an electromagnetic field in accordance with the signal as current passes through the coil.

Meanwhile, the sensor(s) 212 measure at least one operational parameter of the device 100 during its operation, including but not limited to operational voltage, current, or frequency. The sensed parameters are fed back to the processor 202. If any of the sensed parameters are outside of desired limits, the processor 202 can adjust the command signals which in turn adjusts the signal generated by the signal reactor 204.

Furthermore, referring to Fig. 7, during operation of the device 100, the processor 202 periodically obtains an indication of time from a clock external to the pulsed electromagnetic field device 100 via the wireless communications interface 208 (704). The indication of time is preferably obtained as Unix Epoch Time, or other Universally Controlled Time. The processor 202 then compares this time indication (706) with an indication of time obtained from an internal system clock (not shown) of the pulsed electromagnetic field device 100 (702). Based on the comparison, the processor 202 may then correct a phase locked loop circuit on the PCB 110 in order to correct the internal system clock (708). This allows accurate frequency generation by the device 100 to be maintained because the frequency of the pulsed electrical signals generated by the signal reactor 204 is based on the internal system clock and phase locked loop circuit.

Figs. 3-6 illustrate several forms of signals that may be generated by the device 100 for PEMF regeneration and energization of cells. Each figure corresponds to a different waveform associated with a different program, as stored by the memory 210.

Fig. 3 illustrates a modified sawtooth waveform 300. The modified sawtooth shape is applied both for the short-term control (envelope shape) and for the long-term control (signal strength). This waveform 300 may be referred to as “SawONE” and is configured to regenerate recharge cells faster and more intensively than conventional PEMF devices.

The magnetic field function is provided by B ~ F(t⁴-t²+t).

In this example, the math function for calculating the amplitude form of the modified sawtooth waveform 300 of SawONE is provided by:

F(t) = 1 + (1 + 4t (t-k))(t-1) where t = time (normalized 0 < t < 1); k = form factor (0.25 < k < 0.75).

The phase and polarity can be adjusted based on the desired treatment. A pre-stress period 306 is expressed at the beginning of each ramp 302 of the modified sawtooth waveform 300. The pre-stress period 306 is defined as the portion of the ramp 302 prior to an inflection point 304 in the ramp 302. The inflection point 304 is configured to provide a small pause in the speed of increase of the magnetic field in order for the cells to adjust to the field, before receiving a stronger intensity of field. This can help to reduce irritation and stress of the cells.

Fig. 4 illustrates another modified sawtooth waveform 400. The modified sawtooth shape is applied both for the short-term control (envelope shape) and for the long-term control (signal strength). This waveform 400 may be referred to as “SawTWO” and is configured to be powerful in order to recharge targeted body tissues or organs through targeted treatment or therapy.

The math function for calculating the amplitude form of the modified sawtooth waveform 400 of SawTWO is provided by:

F(t) = (sin(51 / TT - 0.02))^1/kt where t = time (normalized 0 < t < 1); and k = form factor (k > 1).

The phase and polarity can be adjusted based on the desired treatment.

Similarly to SawONE, the waveform 400 of SawTWO also comprises a pre-stress period 306 at the beginning of each ramp 302. However, the magnetic field increases more rapidly after the inflection point 304 for the SawTWO waveform 400, providing a more powerful treatment as the magnetic field is sustained close to the maximum for a longer period relative to SawONE.

Fig. 5 illustrates another modified waveform 500. The modified shape is applied both for the short-term control (envelope shape) and for the long-term control (signal strength). This waveform 500 may be referred to as “PulseWave” and is configured for destructive use, for example to disable pathogens. Here, a quasi-sine signal is pulse-width modulated by a square signal. The duty cycle of the PulseWave is from 1 to 50 %. Reducing the duty cycle increases the high harmonics of the wave. Embodiments which are rich in harmonics make it possible to target desired frequencies that are different from the fundamental frequency of the signal. This waveform 500 therefore enables the pathogens to be affected by the spectrum of frequencies as a result of the signal harmonics.

The skilled person will understand that it is also possible to use the envelope shapes 300 and 400 provided in Figs. 3-4 for modulation, while retaining all the advantages they confer, as discussed above.

Figs. 6A and 6B also illustrate another modified sawtooth waveform 600. The modified sawtooth shape is applied both for the short-term control (envelope shape) and for the long-term control (signal strength). An example of long-term control is illustrated in Fig. 6C. The waveforms 600A and 600B of Figs. 6A and 6B may be referred to as “SuperSaw” and “AdvancedSaw” respectively and are configured to be an ideal waveform for regenerative treatment or therapy. The magnetic field function is provided by B ~ F(...t^m - tⁿ + t + t^1/q - t^1/p...). The phase and polarity can be adjusted based on the desired treatment. Variables m, n, q, and p are natural numbers that determine the shape of the signal envelope. In general, m = n+1 , i.e., p=k+1 , for example in AdvancedSaw:

B = k ( t⁵ - 1² + t^1/2 ) + p where t = time (normalized from 0 to 1) k = 0.25 and p = 0 ... for 0 < t < 0.5 k = 1.75 and p = 0.1221 ... for 0.5 < t < 1.

The math function for the modified sawtooth waveform 600 of SuperSaw is provided by: B = k (1 -sin (2qnt) ) ( t⁵ - 1² + t^1/2 ) + p for example, where: t = time (normalized from 0 to 1); q = 11 which is the 11^th harmonic; k = 1/8 and p = 0 ... for 0 < t < 0.5; k = 7/4 and p = 0.1221 ... for 0.5 < t < 1.

The SuperSaw waveform 600 comprises a pre-stress period 306 at the beginning of each ramp 302. Following the pre-stress period 306, the magnetic field increases rapidly to provide a full power period 604. Similarly to the SawTWO waveform 400, the full power period 604 is configured to provide a powerful treatment as the magnetic field is sustained close to the maximum throughout the period 604.

The SuperSaw waveform 600 also comprises a relaxation period 602. The relaxation period 602 provides a period of minimum magnetic field between each ramp 302 and each cliff 606 of adjacent periodic sawtooth waveforms. This is configured to provide a period for the cells to relax to avoid resonance side effects and reduce cell irritation.

Fig. 6C illustrates a long-term envelope 600C of a signal for generation of an electromagnetic field. The long-term envelope 600C comprises a relaxation period 602C, a pre-stress period 306C, and a full power period 604C. The long-term envelope 600C itself may also be periodic.

The function of the pre-stress period 306C is:

0.5( si n( 10t I TT))^1/‘ (0 < t < 0.5 normalized)

0.5 + 0.5( sin (5t/iT + /8))^1/10‘ (0.5 < t < 1 normalized)

The duration of the relaxation period 602C may be from 5 to 10 seconds.

The duration of the pre-stress period 306C may be from 1 to 5 seconds. The duration of the full power period 604C may be from 10 to 30 seconds.

It will be appreciated from the discussion above that the embodiments shown in the Figures are merely exemplary, and include features which may be generalised, removed, or replaced as described herein and as set out in the claims.

For example, whilst the device 100 shown in Fig. 1A comprises an electromagnetic field generation means (not shown), the PEMF device 800 shown in Fig. 8A shows a housing 102 which instead comprises an external electromagnetic generation means port 802. The external electromagnetic generation means port 802 is configured to couple to an external electromagnetic generation means, such as the device 804 shown in Fig. 8B. The external electromagnetic generation device 804 comprises a housing 808 which houses a coil 810, wherein the coil is configured to generate a pulsed electromagnetic field based on the pulsed electric signal output from the amplifier 206 of the PEMF apparatus 800. In this example, the housing 808 is made of a flexible material to form a flexible pad. This may facilitate the pad to be deformed around a body part of the user to enable targeted therapy or treatment to the specific body part. The signal is transferred between the PEMF apparatus 800 and the external electromagnetic generation device 804 via an electrical coupling between the external electromagnetic generation means port 802 and a plug 806 of the external electromagnetic generation device 804. Fig. 8C shows an alternative external electromagnetic generation device 804 to that of Fig. 8B, which instead comprises two coils 810. The skilled person will understand that the PEMF device 800 would also be suitable for use with other external electromagnetic generation devices, such as the electromagnetic generation device of Fig. 10C.

Figs. 9A and 9B shows another embodiment of a PEMF device 900 of the present invention. In this example, the PEMF device 900 comprising a housing 102 having an approximately oval cross-section.

The exterior of the housing 102 comprises a button 104. The button 104 is configured to receive user input in order to control operation of the PEMF device 900. The housing 102 also comprises an LED light 902, wherein the LED light is arranged to surround the button 104 in this example. Illumination of the LED light 902 is configured to provide an indication of the operation and/or status of the device 900, for example wherein different coloured illuminations may indicate different operational modes.

The device 900 further comprises a coil 810 which provides an electromagnetic field generation means. In this embodiment, the device 900 comprises a battery 904 and is battery-powered. The housing 102 may further comprise a charging port 906, such as a USB port, configured to recharge the battery 904. Alternatively, or in addition, the port 906 may be configured to receive a connection to a powerful power source to power the device 900. The port 906 may additionally be configured as a debug port or programming port to the device 900.

Figs. 10A and 10B depict another embodiment of a PEMF device 1000. The PEMF device 1000 comprises a housing 102 which contains a PCB 110 and battery 904, configured to power the PCB 110. The housing 102 also comprises a display 106 and at least one button 104. The PCB 110 is substantially the same as that described with reference to Fig. 2 and is configured to generate a pulsed electrical signal suitable for generating a pulsed electromagnetic field. However, similarly to the embodiment shown in Fig. 8A, the device 1000 does not comprise an integral electromagnetic field generation means. Instead, the housing 102 of the device 1000 further comprises an external electromagnetic generation means port 802 configured to couple to an external electromagnetic generation means, such as the device 804 shown in Figs. 8B-8C, or the device 1010 shown in Fig. 10C. The external electromagnetic generation device 1010 comprises a flexible belt 1012 which houses a plurality of coils 810, wherein each coil 810 is configured to generate a pulsed electromagnetic field based on the pulsed electric signal output from the PEMF device 1000. In this example, the belt 1012 comprises three coils 810, however the skilled person will understand that any other number of coils may be used, for example two or more coils. The flexible belt 1020 is configured to be wrapped around a body part of the user, such as a portion of the torso, or a limb. This may facilitate targeted therapy or treatment to the specific body part. The signal is transferred between the PEMF device 1000 and the external electromagnetic generation device 1010 via an electrical coupling between the external electromagnetic generation means port 802 and a plug 806 of the external electromagnetic generation device 1010. The skilled person will understand that the flexible belt 1020 may additionally or instead be used with other PEMF devices, for example PEMF devices 100 or 800.

In the context of the present disclosure other examples and variations of the apparatus and methods described herein will be apparent to a person of skill in the art.

Claims

CLAIMS:

1 . A pulsed electromagnetic field apparatus comprising: a pulse generator, configured to generate a pulsed electrical signal; an electromagnetic field generation means, configured to generate a pulsed electromagnetic field based on the pulsed electrical signal from the pulse generator; and a non-transitory computer readable storage medium comprising non- transitory instructions configured to cause the pulse generator to generate a pulsed electrical signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field comprising a modified sawtooth waveform comprising a pre-stress period.

2. The pulsed electromagnetic field apparatus of claim 1 wherein the non-transitory instructions are configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field comprising the modified sawtooth waveform, wherein each ramp of the modified sawtooth waveform comprises an inflection point, such that a portion of the ramp prior to the inflection point defines a pre-stress period.

3. The pulsed electromagnetic field apparatus of any preceding claim wherein the non-transitory computer readable storage medium comprises non-transitory instructions configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F{t²⁽ⁿ⁺¹⁾-t²ⁿ+t²⁽ⁿ’¹⁾ ... +t}where t is time.

4. The pulsed electromagnetic field apparatus of any preceding claim wherein the non-transitory computer readable storage medium comprises non-transitory instructions configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F(t) = (sin(5 1 1 IT- 0.02))^1/kt, where t is time, and k is a form factor.

5. The pulsed electromagnetic field apparatus of any preceding claim wherein the non-transitory instructions are configured to cause the pulse generator to generate a pulsed electrical signal which in turn causes the electromagnetic field generation means to generate a pulsed electromagnetic field comprising a modified sawtooth waveform comprising a relaxation period. The pulsed electromagnetic field apparatus of claim 5, wherein the non-transitory instructions are configured to cause the modified sawtooth waveform to comprise a period of minimum field between each ramp and each cliff of adjacent periodic sawtooth waveforms, such that a portion of the waveform after each cliff defines a relaxation period. The pulsed electromagnetic field apparatus of claim 6 wherein the non-transitory computer readable storage medium comprises non-transitory instructions configured to cause the electromagnetic field generation means to generate a pulsed electromagnetic field with function F(... t^m - tⁿ + 1 + t^1/q - t^1/p... ), where t is time and n, m, p and q are a positive natural integers. A pulsed electromagnetic field apparatus comprising: a pulse generator, configured to generate a pulsed electrical signal; an electromagnetic field generation means, wherein the electromagnetic field generation means is configured to generate a pulsed electromagnetic field based on the pulsed electrical signal from the pulse generator; and a non-transitory computer readable storage medium comprising non- transitory instructions configured to cause the pulse generator to modulate a quasisine signal by a square waveform using pulse width modulation. A pulsed electromagnetic field apparatus comprising: a pulse generator, configured to generate a pulsed electric current having a frequency; an internal system clock, wherein the frequency of the pulsed electric current is configured to be based on the internal system clock; an electromagnetic field generation means, wherein the electromagnetic field generation means is configured to generate a pulsed electromagnetic field based on the pulsed electric current from the pulse generator; a wireless communication interface configured to obtain an indication of time from a reference clock; and a feedback circuit configured to adjust the internal system clock based on the obtained indication of time from the reference clock.

10. The pulsed electromagnetic field apparatus of claim 9 wherein the feedback circuit is a phase locked loop.

11. The pulsed electromagnetic field apparatus of any of claims 9 to 10 wherein the reference clock is a Unix Epoch Clock.

12. The pulsed electromagnetic field apparatus of any of claims 9 to 11 wherein the pulse generator comprises a crystal oscillator, and wherein the internal system clock is based on the crystal oscillator.

13. The pulsed electromagnetic field apparatus of claim 12 wherein the crystal oscillator has a stability of < 20 parts per million, ppm.

14. The pulsed electromagnetic field apparatus of any preceding claim wherein the electromagnetic field generation means comprises a coil.

15. The pulsed electromagnetic field apparatus of any preceding claim wherein the pulse generator further comprises: a signal reactor configured to generate digital pulsed electrical signals; and an amplifier configured to convert the digital pulsed electrical signals from the signal reactor into analog pulsed electrical signals.

16. The pulsed electromagnetic field apparatus of claim 15 wherein the signal reactor is configured to generate the digital pulsed electrical signals by modulating a carrier frequency by a therapeutic frequency, wherein the carrier frequency is a harmonic of the therapeutic frequency. The pulsed electromagnetic field apparatus of any of claims 15 to 16 wherein the amplifier is configured to perform the digital to analog conversion using discrete output transistors. The pulsed electromagnetic field apparatus of claim 17 wherein the amplifier is a hybrid AB-D amplifier. The pulsed electromagnetic field apparatus of any preceding claim further comprising: a sensor configured to measure the output electromagnetic field; and a feedback loop configured to monitor the electromagnetic field detected by the sensor and control the operation of the pulse generator based on the output electromagnetic field. The pulsed electromagnetic field apparatus of any preceding claim wherein the electromagnetic field generation means further comprises a bifilar antenna configured to generate scalar waves. The pulsed electromagnetic field apparatus of any preceding claim further comprising a wireless communication interface configured to communicate with a remote device. The pulsed electromagnetic field apparatus of any preceding claim further comprising a linear power supply. The pulsed electromagnetic field apparatus of any preceding claim comprising a first and a second electromagnetic field generation means, wherein each electromagnetic field generation means is configured to generate a pulsed electromagnetic field having a frequency, wherein the two electromagnetic field generation means are configured such that the frequency of the pulsed electromagnetic field of the first electromagnetic field generation means is out of phase with the frequency of the pulsed electromagnetic field of the second electromagnetic field generation means.

24. The pulsed electromagnetic field apparatus of any preceding claim comprising a first and a second electromagnetic field generation means, wherein each electromagnetic field generation means is configured to generate a pulsed electromagnetic field having a frequency, wherein the two electromagnetic field generation means are configured such that the frequency of the pulsed electromagnetic field of the first electromagnetic field generation means is different to the frequency of the pulsed electromagnetic field of the second electromagnetic field generation means.

25. The pulsed electromagnetic field apparatus of claim 24, wherein each electromagnetic field generation is configured such that the frequency of the pulsed electromagnetic field of the first electromagnetic field generation means is in phase with the frequency of the pulsed electromagnetic field of the second electromagnetic field generation means.

26. A method for maintaining frequency stability of a pulsed electromagnetic field apparatus comprising: obtaining an indication of time from an internal system clock of the pulsed electromagnetic field apparatus; obtaining an indication of time from a second clock, external to the pulsed electromagnetic field apparatus; comparing the indication of time from the internal system clock to the indication of time from the second clock; and adjusting a feedback circuit of the pulsed electromagnetic field apparatus based on the comparison of the indication of time from the internal system clock and the indication of time from the second clock.

27. The method of claim 26 wherein the second clock is a Unix Epoch Clock. 28. The method of any of claims 26 to 27 wherein the feedback circuit is a phase locked loop circuit.