Equipment for treating weeds by microwave

Abstract

The present invention relates to methods and apparatus for treating weeds, and more particularly to treating weeds by microwaves.

Description

Technical Field

[0001] The present disclosure relates to methods and apparatus for treating weeds, and more particularly, to treating weeds by microwaves.

[0002] Technical background of the present invention

[0003] Today, small-scale weed control, for example by individuals or municipal services, is still mainly carried out with herbicides that are sprayed on the weeds in liquid or aerosol form. For example, pressurized tanks are known, which are carried on the back and the user uses a sprayer connected to the tank. Due to the harmful consequences of these means for the environment, people are beginning to turn to alternative environmentally friendly solutions.

[0004] These solutions include, in particular, mechanical removal of weeds or treatment of weeds by treatment with electric current or using gas burners. However, mechanical removal requires too high a treatment frequency, as does treatment with electric current, and is energy inefficient. The use of gas burners is an expensive solution and, due to the associated CO2 emissions, is also ecologically irresponsible. In addition, burning weeds with electric current or gas burners on dry soil carries a risk of fire.

[0005] The use of microwaves for weed control is another environmentally friendly solution, but it is mainly used in large machines that are not suitable for manual use. For example, patent publication CA3089518 describes a device consisting of a portable holder connected via a cable to a voltage source (such as the power grid or a battery). The holder is in the shape of an elongated stalk with a handle at one end and a microwave generator / waveguide combination at the other end. The generator is a magnetron, i.e. an electron tube that generates a high-frequency electromagnetic field.

[0006] However, the weight of the assembly is significant, making the holder heavy and difficult to handle. The device also presents a potential risk to the user due to the high voltage supplied to the generator. Apart from suggesting that the battery be attached to the handle-shaped holder, the housing for the battery is not clearly described, making the assembly even more cumbersome. Therefore, there is a need to develop a compact and user-friendly way to treat weeds with microwaves.

[0007] Overview

[0008] The present disclosure provides a solution to the needs of the prior art as described above. The device includes a portable portion, which includes a microwave generator and a battery for powering the generator. The device further includes a transmission line for transmitting the signal generated by the generator, a holder that can be held by a user at one end thereof, and an antenna system attached to the other end and to which the transmission line is connected. In the antenna system, the signal is converted into microwaves, which are directed to the outside near the area to be treated. The generator is preferably a solid-state generator. The antenna system is intended to quickly heat the area in question to a desired temperature. The device includes a control unit, which is configured to adjust the parameters of the generator and possible antenna system based on input provided by a user and / or by a sensor that detects information about the area to be treated or about other parameters (e.g., the temperature of the generator).

[0009] Since the generator is located in the portable portion and is not attached to the holder itself, the device described in this disclosure is easier to operate than existing devices and is less tiring for its carrier.

[0010] The use of a solid state generator has the further advantage that it consumes less energy than a magnetron and is easier to adjust, making it possible to use the microwave energy generated for weed control more efficiently and also being safer for the user.

[0011] The device also provides a feedback unit that can ensure the safety of the user when treating weeds by distinguishing plant tissue from obstacles (such as human or animal bodies) in the area to be treated. For greater safety, the feedback unit can be configured to reduce the power of the microwave generator or turn off the generator, or block the emission of microwaves, for example using a slidable safety cover.

[0012] Another aspect of the present disclosure relates to an apparatus for treating weeds by microwaves, wherein the apparatus comprises the following components:

[0013] a portion to be carried by a user, the portion comprising a housing within which is arranged a microwave generator and a battery configured to supply power to the generator,

[0014] a holder provided with at least two ends, wherein the holder can be held by a user by one end and wherein an antenna system is attached to the other end, suitable for directing microwaves into the area to be treated,

[0015] A transmission line is used to transmit the microwave signal generated by the generator from the generator to the antenna system.

[0016] Another aspect of the present disclosure relates to a device for treating weeds by microwaves, characterized in that the device comprises the following components:

[0017] a portable part configured to be fixed to the body of a user; wherein the portable part comprises a housing in which a microwave generator is arranged and a power supply for supplying power to said generator;

[0018] a holder provided with at least two ends, wherein the holder can be held by a user by one end and wherein an antenna system is attached to the other end, the antenna system being configured for directing microwaves into the area to be treated;

[0019] • A transmission line configured to transmit microwaves from the microwave generator to the antenna system.

[0020] In an embodiment, the power supply may comprise a power source, preferably a rechargeable and / or replaceable battery.

[0021] In an embodiment, the power supply may comprise a plug for connecting a power cable connected to an external power source and optionally a device for transmitting electrical energy by which the energy of the power source is adjusted to the power requirement of the microwave generator, preferably a transformer.

[0022] In an embodiment, the microwave generator is a solid-state microwave generator; preferably featuring a power consumption of 250W and / or a voltage of 30V.

[0023] In an embodiment, the antenna system comprises three components arranged one after the other:

[0024] - a signal adapter for converting the signal from the transmission line into microwaves,

[0025] - waveguide, and

[0026] -An antenna or a group of antenna elements.

[0027] In an embodiment, the waveguide is an impedance adapter, the impedance of which can be adjusted manually or automatically, so that almost no reflections occur at the transition between the antenna or the group of antenna elements and the area to be treated.

[0028] In an embodiment, the waveguide is a guide having a predetermined impedance such that almost no reflection occurs at the transition between the antenna or antenna element group and the area to be treated when the impedance of the area is within a predetermined range around a value of 377 ohm (ie the impedance of free space).

[0029] In an embodiment, the antenna has an entrance portion coupled to the waveguide and a slot-shaped exit portion along which microwaves are guided to the outside.

[0030] In an embodiment, the housing of the portable part comprises a cooling element configured for cooling the generator and / or the power supply (preferably a battery).

[0031] In an embodiment, the portable holder has two ends, wherein a first end of the portable holder is provided with a handle for a user and the other end thereof is coupled to the antenna system.

[0032] In an embodiment, the portable holder is an elongated handle-shaped holder, wherein a first end of the portable holder is provided with a handle for a user and the other end thereof is coupled to the antenna system.

[0033] In an embodiment, the handle is provided with an input device for a user and / or is provided with an indicator to provide information to the user about the handling of the determined area.

[0034] In an embodiment, the handle-shaped holder is provided with a hollow passage, wherein a portion of the transmission line is located in the hollow passage of the holder.

[0035] In an embodiment, the antenna system and / or the end of the holder is provided with a roller system, by means of which the user can roll the holder on the ground during area treatment.

[0036] In an embodiment, the device comprises a control unit operatively connected to or forming part of the microwave generator and configured to control the operation of the microwave generator based on user input, detected information about the area to be treated and / or detected information about the operation of the device itself.

[0037] In an embodiment, the device comprises a temperature sensor connected to the control unit and wherein the control unit is configured to adjust the operation of the microwave generator based on the measured temperature, preferably by switching off the microwave generator when a predetermined threshold is exceeded.

[0038] In an embodiment, the device comprises a feedback unit configured to detect a change in the impedance of the treatment area outside a predetermined range around an expected value of the impedance and to intervene in the operation of the generator upon detecting said change.

[0039] In an embodiment, the feedback unit is configured to act as a safety measure by preventing microwaves from being emitted from the device whenever the presence of non-weed organic matter and / or inorganic matter is detected in the area to be treated; preferably by reducing the power of the microwave generator to a harmless level, switching off the generator and / or mechanically blocking the emission of microwaves from the antenna system.

[0040] In an embodiment, the device comprises a feedback unit configured to detect impedance changes in the treatment area by measuring and / or determining wave reflection, standing wave ratio and / or reflection coefficient and to intervene in the operation of the generator, preferably preventing microwave emission in the event of

[0041] - wave reflection less than or equal to 30%,

[0042] - Standing wave ratio less than or equal to 8, and / or

[0043] -Reflection coefficient greater than or equal to 0.8.

[0044] In an embodiment, the feedback unit is configured to act as an efficiency measure by dynamically adjusting one or more operating parameters of the microwave generator whenever a decrease in the Q factor is determined; preferably by adjusting the microwave frequency to correspond to a resonant frequency of the treatment zone.

[0045] In an embodiment, the device comprises a feedback unit configured to detect impedance changes in the treatment area by measuring and / or determining wave reflections, standing wave ratios and / or reflection coefficients and to intervene in the operation of the generator in such a case, preferably dynamically adjusting one or more operating parameters of the device

[0046] - wave reflection higher than or equal to 30%,

[0047] - Standing wave ratio greater than or equal to 8, and / or

[0048] - The reflection coefficient is lower than or equal to 0.8.

[0049] Another aspect of the present disclosure relates to a method for treating weeds by microwaves, the method comprising:

[0050] (a) generating microwaves using a microwave generator;

[0051] (b) directing the generated microwaves toward the area to be treated;

[0052] (c) determining the impedance value of the area to be treated by determining wave reflection, standing wave ratio and / or reflection coefficient;

[0053] (d) Continue to guide the generated microwaves under the following conditions:

[0054] - wave reflection less than or equal to 30%,

[0055] - Standing wave ratio less than or equal to 8, and / or

[0056] - a reflection coefficient greater than or equal to 0.8; and / or

[0057] Stop directing the generated microwaves in the following cases

[0058] - wave reflection higher than 30%,

[0059] - Standing wave ratio higher than 8, and / or

[0060] -Reflectance coefficient is less than 0.8.

[0061] (e) Optionally, each time a decrease in the Q factor is determined, dynamically adjusting one or more operating parameters of the microwave generator, preferably by adjusting the microwave frequency to correspond to a resonant frequency of the treatment zone.

[0062] Another aspect of the present disclosure relates to the use of an apparatus as described herein for treating weeds.

[0063] Another aspect of the present disclosure relates to the use of a feedback unit as described herein in a device for treating weeds by microwaves.

[0064] Another aspect of the present disclosure relates to an apparatus for treating weeds by microwaves, wherein the apparatus comprises the following components:

[0065] - a microwave generator and a power supply arranged to supply power to said generator;

[0066] - an antenna system configured to direct the microwaves into the area to be treated,

[0067] - optionally, a transmission line or waveguide configured to transmit microwaves from the microwave generator to the antenna system; and

[0068] - a control unit operatively connected to or forming part of the microwave generator; wherein the control unit is configured to detect a change in the impedance of the treatment area outside a predetermined range around an expected value of the impedance and to intervene in the operation of the device upon detection of said change.

[0069] In an embodiment, the device comprises or is arranged on a vehicle, preferably an autonomous vehicle (AV), or comprises drive means for moving the device over the area to be treated. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The following description of the drawings showing specific embodiments of the present disclosure is merely exemplary in nature and is not intended to limit the present teachings, its application, or uses.

[0071] Throughout the description, claims and drawings, the following numbering is retained: portable part 1; transmission line 2; antenna system 3; holder 4; housing 10; fixing device 11; power supply 12; assembly 13; microwave generator 14; heat exchanger 15; fan 16; connector 17; signal adapter 20; first connecting flange 22; waveguide 23; antenna 24; second connecting flange 25; lateral control device 26; outlet 27; roller system 28; wheels 29; area to be treated 30.

[0072] Figure 1 The device according to its preferred embodiment is shown.

[0073] Figure 2 Shows Figure 1 Device in which components of the portable part 1 are visible.

[0074] Figure 3 Shown as Figure 1 An assembly 13 of a solid state microwave generator 14 and cooling element as part of the device.

[0075] Figure 4 Shown as Figure 1 Antenna system 3 at the end of a holder 4 which is a part of the device.

[0076] Figure 5 Another embodiment of the device according to the preferred embodiment is shown, in which the transmission line 2 is partially incorporated into the holder 4 .

[0077] Figure 6 Shows Figure 5 Another embodiment of the antenna system 3 on the device.

[0078] Figure 7 The antenna system 3 is schematically shown emitting microwaves towards the empty area 30 .

[0079] Figure 8 The antenna system 3 is schematically shown emitting microwaves towards the weeds.

[0080] Fig. 9 It is schematically shown that weeds reflect microwaves back to the antenna system 3 .

[0081] Fig.10 The effect of the Q factor on the resonant frequency bandwidth is shown. DETAILED DESCRIPTION

[0082] The present disclosure will be described with respect to particular embodiments but the present disclosure is not limited thereto but only by the claims.Any reference signs in the claims should not be construed as limiting the scope thereof.

[0083] As used herein, the singular form "a," "an," and "the" include singular and plural referents unless the context clearly dictates otherwise.

[0084] As used herein, the terms "comprising, comprises, and comprised of" are synonymous with "including, includes, or "containing, contains," and are inclusive or open-ended and do not exclude additional, unrecited components, elements, or method steps. The terms "comprising, comprises, and comprised of," when referring to the recited components, elements, or method steps, also include embodiments consisting of the recited components, elements, or method steps. The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within the corresponding ranges as well as the recited endpoints.

[0085] In addition, unless otherwise stated, the terms first, second, third, etc. in the specification and claims are used to distinguish similar elements, and are not necessarily used to describe order or chronological order. It should be understood that the terms used in this way are interchangeable where appropriate, and the embodiments of the present disclosure described herein can operate in other orders except the order described or illustrated herein. Unless otherwise defined, all terms (including technical and scientific terms) used when disclosing the present invention have the meanings commonly understood by those of ordinary skill in the art to which the present disclosure belongs. By further guidance, the definitions of the terms used in the specification are included to better understand the teachings of the present invention. The terms or definitions used herein are only provided to help understand the present invention.

[0086] References throughout this specification to "one embodiment" or "an embodiment" mean that a specific feature, structure, or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present invention. Therefore, throughout this specification, the phrase "in one embodiment" or "in an embodiment" does not necessarily refer to the same embodiment in various places. In addition, in one or more embodiments, these features, structures, or characteristics may be combined in any suitable manner, as will be apparent to those skilled in the art from this disclosure. In addition, although some embodiments described herein include some but not other features included in other embodiments, as will be understood by those skilled in the art, the combination of features of different embodiments is intended to be within the scope of the present invention and to form different embodiments. For example, in the following claims and descriptions, any claimed or described embodiment may be used in any combination.

[0087] The terms "left", "right", "front", "back", "top", "bottom", "over", "under", etc., if any, in the specification and claims are used for descriptive purposes and are not necessarily used to describe unchanging relative positions. It should be understood that the terms so used are interchangeable where appropriate, such that the embodiments described herein are, for example, capable of operating in orientations other than those illustrated or otherwise described herein. As used herein, the term "coupled" is defined as connected directly or indirectly in an electrical or non-electrical (i.e., physical) manner. Objects described herein as "adjacent" to each other can be in physical contact with each other, in close proximity to each other, or in the same general area or region as each other, depending on the context in which the phrase is used. In this document, the appearance of the phrase "in one embodiment" or "in one aspect" does not necessarily refer to the same embodiment or aspect.

[0088] As used herein, the term "substantially" refers to the complete or almost complete range or degree of an action, characteristic, property, state, structure, item or result. For example, an object that is "substantially" closed will mean that the object is completely or almost completely closed. In some cases, the exact degree of allowance for deviations from absolute completeness may depend on the specific context. However, in general, the proximity of completion will be to have the same overall result as having obtained absolute and complete completion. When used in a negative sense to refer to the complete or almost complete absence of an action, characteristic, property, state, structure, item or result, the use of "substantially" is equally applicable. For example, a composition that is "substantially free of" particles either completely lacks particles, or almost completely lacks particles so that its effect is the same as completely lacking particles. In other words, a composition that is "substantially free of" a certain ingredient or element may still actually contain this ingredient or element, as long as it has no measurable effect.

[0089] As used herein, the term "about" is used to provide flexibility for numerical range endpoints by specifying that a given value can be "slightly above" or "slightly below" the endpoint. Unless otherwise stated, the use of the term "about" in accordance with a specific numerical value or numerical range should also be understood to support such numerical terms or ranges without the term "about". For example, for the sake of convenience and brevity, a numerical range of "about 50 angstroms to about 80 angstroms" should also be understood to support a range of "50 angstroms to 80 angstroms". In addition, it should be understood that in this specification, even when the term "about" is used, support for actual numerical values ​​is provided. For example, the listing of "about" 30 should be interpreted as supporting not only values ​​slightly above and slightly below 30, but also the actual numerical value of 30.

[0090] Throughout this specification, reference may be made to a device, structure, system, or method that provides "improved" performance. It should be understood that, unless otherwise stated, such "improvement" is a measure of benefit obtained based on a comparison with a device, structure, system, or method in the prior art. Furthermore, it should be understood that the degree of improvement in performance may vary between the disclosed embodiments, and no equality or consistency in the amount, degree, or realization of improved performance is considered to be universally applicable.

[0091] In addition, embodiments of the present disclosure may include hardware, software, and electronic components or modules, which, for the purpose of discussion, may be shown and described as if most components are implemented only in hardware. However, those of ordinary skill in the art will recognize, based on a reading of the detailed description, that in at least one embodiment, the electronic-based aspects of the present disclosure may be implemented in software (e.g., instructions stored on a non-transitory computer-readable medium) that may be executed by one or more processing units (e.g., microprocessors and / or application-specific integrated circuits (“ASICs”)). Therefore, it should be noted that the present invention may be implemented using a plurality of hardware- and software-based devices and a plurality of different structural components. For example, the “server” and “computing device” described in the specification may include one or more processing units, one or more computer-readable medium modules, one or more input / output interfaces, and various connectors (e.g., a system bus) connecting components.

[0092] According to previous studies, it is known that raising the internal temperature of at least a portion of the plant body to about 50°C will result in the eventual death of common weeds. The optimal temperature may depend on the target plant type and the plant growth stage. The present invention has been found to be particularly suitable for controlling the growth of immature weeds (i.e. weed plants that are still in the early stages of growth and have thin stems). In the immature stage, the weeds have already grown into seedlings with thin stems. However, it is clear that the present invention can also be used to control weeds in the seed stage (i.e. seeds present in the ground) or in the fully grown stage (i.e. with thicker stems).

[0093] In this specification, "weeds" refers to plants that are considered undesirable in a given situation or environment, and generally includes non-crop plants in agricultural fields. Examples of weeds are, inter alia, thistle, yarrow, common purslane, red clover, spring polygonum, chamomile, stinging nettles, grass, Bermuda grass, bindweed, broadleaf plantain, burdock, white quinoa, dandelion, goldenrod, aster and asteraceae, spurge, milk thistle, dock and sorrel, St. John's wort, wild carrot, white clover, wood sorrel, nightshade, etc.

[0094] By controlling the growth of weeds with the aid of the invention of the present disclosure, the growth of desired plants such as crops can be improved, which can increase the yield of agricultural fields. Examples of crops are, in particular, sugar beets, fodder beets, beetroot, sugar cane, barley, corn, millet, rye, wheat, cassava, potatoes, chicory, peas, beans, cabbage, carrots, flax, rapeseed, sunflowers, or crops such as brassicas, fruit trees, berry bushes, etc.

[0095] To produce the above-mentioned heating, the invention of the present disclosure utilizes microwaves. Microwaves exist in the electromagnetic spectrum in the frequency range between 300MHz and 300GHz. The microwave energy absorbed depends directly on the frequency of the microwaves, i.e., a higher microwave frequency means a shorter wavelength, and therefore means more microwave energy. Therefore, generating microwaves at a higher frequency can make it possible to heat targets (such as weeds) faster, at the expense of smaller target size or smaller volume. Increasing the frequency of microwaves also reduces the depth to which microwaves can penetrate targets (such as plant cells). Rapid heating produces a pressure effect that can rupture the cells of the plant, resulting in death from the inside out. Therefore, the weeds will not be burned, and therefore there will be no fire hazard, which means that the device can be safely applied to both wet and dry soils.

[0096] The following is a first overview of the various components of the invention of the present disclosure, and then a specific embodiment will be described in more detail. This first overview is intended to help readers understand the technical concept more quickly, but is not intended to determine its most important or most basic features, nor is it intended to limit the scope of the invention.

[0097] Figure 1 One possible embodiment of a device according to the invention is shown. The device comprises a portable part 1 on the back of the user, which is connected to an antenna system 3 via a transmission line 2. The antenna system 3 is attached to the end of a holder 4, the opposite end of which is held by the user. In the embodiment shown, the holder 4 is in the shape of an elongated handle; the holder is a handle-shaped holder.

[0098] As in Figure 2 As can be seen in the figure, the portable part 1 comprises a housing 10 provided with shoulder straps 11 so that the assembly can be carried simply like a backpack / rucksack. The length of the shoulder straps can be adjusted so as to securely fasten the portable part 1 to the upper body of the carrier. Obviously, the housing 10 can be provided with another or additional fixing device 11, which allows the portable part to be fixed to a part of the body other than the back or shoulder of the user. As an example, the housing may include an abdominal plate that allows the portable part to be supported on the abdomen of the carrier, or a belt that secures the portable part to the hips of the user, etc. The secure fastening of the portable part can be achieved by providing fastening means known in the prior art, such as Velcro, buttons, buckles or hook connection mechanisms, etc. Therefore, it is understood by those skilled in the art that the configuration of the portable part can be adjusted according to the desired comfort of the carrier and / or the weight of the portable part.

[0099] The housing 10 includes a power source 12, preferably in the form of a portable battery, which is advantageously rechargeable and / or replaceable, and Figure 313. The assembly 13 comprises a solid-state microwave generator 14 fixed to a heat exchanger 15. Two fans 16, also powered by batteries, are mounted on the side edges of the heat exchanger for blowing air through the heat exchanger to cool the microwave generator 14 and the battery 12. The housing 10 must allow airflow in and out of the exchanger 15 and is therefore breathable at least where necessary. The heat exchanger 15 can be produced according to any existing design intended to take away heat from a heat source mounted on the exchanger and / or positioned in contact with it. The microwave generator 14 and the fans 16 can be connected to the battery 12 via electrical conductors (not shown in the figure).

[0100] Obviously, the assembly may be provided with another or additional cooling element, which is configured to cool the microwave generator and / or the power source, preferably the battery. The combination of the heat exchanger 15 and the fan 16 is a preferred embodiment of the cooling element. Other embodiments of cooling elements suitable for cooling the generator 14 and the battery 12 are possible within the scope of the present invention. According to an alternative embodiment, the cooling element comprises a liquid cooling system, which comprises an arrangement of liquid pipelines and at least one pump for pumping liquid coolant through the liquid cooling system. The liquid cooling system may include additional features commonly used in the art for such systems, including but not limited to accessories, adapters, pipelines, valves, etc.

[0101] Preferably, the housing 10 also comprises an electronic control unit (not shown in the figures), which is powered by a battery 12 and is intended to control the operation of the generator 14 and the fan 16 according to a control algorithm which itself is not defined within the scope of the invention, but which at least allows the generator to be switched on and off and advantageously also allows the power or other parameters of the generator to be controlled. To this end, operating means are provided, either inside or outside the housing, or on the holder, for example in the form of operating buttons at the level of a handle. In the latter case, there is preferably wireless communication between the holder 4 and the control unit. The control unit may also form an integral part of the generator 14, as is the case with certain existing types of microwave generators that can be used in the device according to the invention (see below). In Figure 3 A connector 17 can also be seen on the solid-state microwave generator 14 connected to the transmission line 2. Solid-state microwave generators and transmission lines and connectors suitable therefor are known per se. The transmission line 2 is preferably a coaxial line intended to transmit high-frequency electrical signals from the generator 14 to the antenna system 3.

[0102] The solid-state microwave generator may be a generator commercially available on the market. Preferably, a generator with an integrated control unit is used, which makes it possible to detect changes in the impedance of the load constituted by the transmission line, the antenna system and the treatment area and to adapt the delivered power thereto. This will be discussed in more detail further in this specification.

[0103] In some embodiments, the solid-state microwave generator operates at a power between 25 W and 400 W, preferably between 50 W and 375 W, or between 75 W and 350 W, or between 100 W and 325 W, or between 125 W and 300 W, or between 150 W and 275 W, or between 175 W and 250 W, or between 175 W and 225 W (e.g., 200 W). A combination of power amplifiers can be used to achieve the desired operating power; for example, to power a 200 W semiconductor generator, two 100 W amplifiers can be used, or four 50 W amplifiers, etc.

[0104] The voltage required to power the solid-state generator may be about 30 V. The microwave generator may be configured to generate microwaves typically in the frequency range of 1.0 GHz to 20.0 GHz. For usability, i.e., efficient and safe killing of weeds, the microwaves will preferably be in the frequency range of from at least 2.0 GHz to at most 6.0 GHz, preferably at least 3.0 GHz, more preferably at least 4.0 GHz, still more preferably at least 5.0 GHz, still more preferably about 5.8 GHz.

[0105] The microwaves generated may have a frequency of at least 2.0 GHz, such as 2.1 GHz, 2.2 GHz, 2.3 GHz, 2.4 GHz, 2.5 GHz, 2.6 GHz, 2.7 GHz, 2.8 GHz or 2.9 GHz; preferably at least 3.0 GHz, such as 3.1 GHz, 3.2 GHz, 3.3 GHz, 3.4 GHz, 3.5 GHz, 3.6 GHz, 3.7 GHz, 3.8 GHz or 3.9 GHz; still more preferably at least 4.0 GHz, such as 4.1 GHz, 4.2 GHz, 4.3 GHz, 4.4 GHz, 4.5 GHz, 4.6 GHz, 4.7 GHz, 4.8 GHz or 4.9 GHz; still more preferably at least 5.0 GHz, such as 5.1 GHz, 5.2 GHz, 5.3 GHz, 5.4 GHz, 5.5 GHz, 5.6 GHz, 5.7 GHz, 5.8 GHz or 5.9 GHz.

[0106] The microwaves generated may be in a frequency range of from a minimum of 2.0 GHz to a maximum of 6.0 GHz; more preferably at least 2.5 GHz to a maximum of 6.0 GHz; still more preferably at least 3.0 GHz to a maximum of 6.0 GHz; still more preferably at least 3.5 GHz to a maximum of 6.0 GHz; still more preferably at least 4.0 GHz to a maximum of 6.0 GHz; still more preferably at least 4.5 GHz to a maximum of 6.0 GHz; still more preferably at least 5.0 GHz to a maximum of 6.0 GHz; still more preferably at least 5.5 GHz to a maximum of 6.0 GHz; still more preferably at least 5.6 GHz to a maximum of 5.9 GHz, or at least 5.7 GHz to a maximum of 5.9 GHz.

[0107] Prior art systems are typically designed to transmit microwaves to a wide target area at relatively low frequencies (i.e., below 2.0 GHz), and thus may affect all plant tissues, roots, and seeds growing in the target area, i.e., including non-weed plants such as crops or leaves. Thus, the use of low frequency, non-focused microwaves to treat weed plants requires high power, which in turn requires longer treatment times and / or heavier batteries or generators. Additionally, such microwaves also have unnecessarily deep penetration depths at relatively low frequencies. Thus, even though similar prior art systems may show potential for controlling weed growth by microwaves, they fail to achieve the efficiency required for industrial applications.

[0108] A typical microwave generator suitable for use in the present invention provides an integrated solution designed to generate and transmit microwave power. The microwave generator may be functionally adjustable so that the timing or properties of the microwaves may be controlled. In particular, the microwaves may be generated on demand (i.e. in response to an input signal that may be sent to the generator by a control system). Additionally, the properties of the microwaves (such as power or amplitude and / or frequency) may be adjustable at least to some extent.

[0109] Figure 4 An antenna system 3 according to a possible embodiment of the invention is shown in FIG.

[0110] The antenna system 3 includes a signal adapter 20, which is provided with a connector 21, which is connected to the transmission line 2 and mechanically attached to the end of the holder 4. The signal adapter 20 is a component that converts the electromagnetic microwave signal from the coaxial cable into a series of microwaves that are continuously emitted. The adapter 20 is hollow, thereby defining a hollow space that preferably has a square or rectangular cross-section. A small antenna is located in the hollow space, which is connected to the cable 2 and emits microwaves at a frequency and amplitude as transmitted by the generator 14. The microwaves propagate through the hollow space that acts as a waveguide, and further through an additional waveguide connected to the adapter 20. This type of adapter 20 is known in the prior art, and existing types of adapters can be used in devices according to the present disclosure.

[0111] The signal adapter 20 is coupled via a first coupling flange 22 to two additional components, namely an impedance adapter 23 and an antenna 24, which are coupled to each other via a second coupling flange 25. In addition to providing one or two coupling flanges, the coupled components can also be produced as one unified component.

[0112] The impedance adapter 23 is a waveguide with the same cross section as the signal adapter 20, so that the microwaves propagate further through the hollow space defined by the impedance adapter 23. However, the adapter is provided with three lateral control devices 26. These lateral control devices are cylinders with manually retractable plunger elements. In other words, the adapter 23 is a component known in the prior art as a "stub tuner". The plunger forms a "stub", and the position of the plunger determines the impedance of the load formed by the transmission line 2, the antenna system 3 and the processing area.

[0113] In the embodiment shown, the antenna 24 is an element having a square or rectangular inlet matching the cross section of the impedance adapter 23 and having a slot-shaped (i.e., elongated) outlet 27. The microwaves are output near the weeds via this outlet 27, through which the microwaves are heated to a temperature and / or pressure that destroys the weeds. However, the shape of the antenna is not fixed within the scope of the invention, and other shapes can be used, such as a horn antenna (as in the case of a loudspeaker) or a wire antenna in which the cross section of the outlet is larger than the cross section of the inlet. Suitable types of horn antennas are, for example, pyramidal horns, conical horns, fan-shaped horns, exponential horns, etc. However, a shape with a slot-shaped cross section 27 is useful because the width of the outlet (which is the length of the elongated outlet portion) can be optimized so that the impedance of the outlet corresponds as well as possible to the impedance of the area to be treated, while the height of the outlet has little or no effect on the impedance. Then, the height can be designed as a function of the power of the generator and the maximum breakdown voltage.

[0114] The antenna may also be formed of one or more antenna elements, such as a plurality of horn antennas. In an embodiment, at least one antenna element, preferably all antenna elements of the plurality of antenna elements, may be a dipole antenna. This type of antenna is typically formed of two identical conductive elements, such as metal wires or metal rods. A dipole antenna may take a variety of shapes, and the present invention is by no means limited to a certain type.

[0115] In an embodiment, at least one antenna element, preferably all antenna elements of the plurality of antenna elements, may be a patch antenna. This type of antenna is typically made up of a piece of metal foil having a specific shape, which is etched on the surface of a substrate and has a metal foil ground plane on the other side. As an alternative, the patch antenna may be made up of a metal patch mounted above the ground plane with the aid of a dielectric spacer. Patch antennas may take a variety of shapes, and the present invention is by no means limited to a certain type. In particular, patch antennas etched into the surface of a printed circuit board may also be referred to as microstrip antennas. The use of patch / microstrip antennas may have the advantage of reducing the system footprint and provides the possibility of integrating the antenna element into a protective housing.

[0116] In terms of the impedance of this space, the area to be treated in the case of microwave treatment of weeds is essentially considered as open space. Even when plants are located in this area, the impedance is not much different from the theoretical impedance of free space (377 ohm), which is known from spatial wave physics. Now, considering that the impedance of the treatment area is about 377 ohm, the device of the present invention is designed so that when the device is used to treat this area, no or as little wave reflection occurs at the transition between the antenna and the area to be treated. This condition (i.e., the absence of reflection) is a condition for the maximum transmission of the power of the generator to the treatment area. In the terms of wave physics, an "impedance matching" condition is created; in other words, the impedance of the load matches the impedance of the source.

[0117] To make it easier to understand the impedance matching conditions, two exemplary scenarios will be discussed below. It should be understood that these examples represent illustrative simplifications of physical principles, and the actual implementation of the technology will be further described below in this disclosure.

[0118] Figure 7 A first scenario is shown where the antenna system 3 transmits microwaves onto an open area 30 (e.g., soil without weeds). Due to the lack of reflective material, the transmitted microwaves will scatter on the soil surface, which will result in power losses. The antenna system can detect the amount of microwave power (or lack thereof) reflected to determine the degree of reflectivity and the corresponding impedance value, which for an open area will correspond to a free space value of 377 ohms.

[0119] Figure 8 A second scenario is shown where the antenna system 3 transmits microwaves towards an area where weeds are growing. The weeds will absorb the microwaves, but at least a portion will be reflected back to the source antenna, e.g. Fig. 9The presence of weeds will thereby change the impedance value of the area away from the free space value mentioned above. The reflection coefficient and the corresponding impedance value of the treatment area can be determined based on the standing wave ratio within the antenna, which is affected when the transmitted wave interferes with the reflected wave. In this way, the presence of weeds in the treatment area can be effectively detected without increasing the complexity of the equipment using cameras or sensors. The actual implementation of such impedance monitoring will be discussed below.

[0120] exist Figure 4 In the embodiment shown, an impedance adapter 23 can be used to establish impedance matching conditions for a determined process. This can be accomplished by connecting the signal adapter 20 to a test generator via a coaxial cable that is the same length and the same gauge as the transmission line 2 of the device. The test generator includes or is connected to a measurement device that measures the load impedance so that the "stub" 26 can be set to "impedance matching". During the actual process, the stub 26 is then maintained at these set positions. However, Figure 4 The exemplary embodiments are not particularly suitable for large-scale use by inexperienced users who are not familiar with mechanically setting up "stub tuners" or generators.

[0121] Figure 5 Another embodiment of the device is shown in which the generator is not provided with or connected to a user-visible measuring device and the antenna system is not provided with a "stub tuner". In this embodiment, the antenna system 3 comprises a waveguide whose impedance is pre-configured according to the treatment of an area with an impedance of 377 ohms or slightly deviating from this value, which covers an open area with a large part of vegetation cover. Omitting the "stub tuner" can reduce the operating complexity of the device, thereby bringing the benefit of user-friendliness to inexperienced users. As Figure 5 As shown, the length of the guide element can therefore also be limited so that it forms almost one continuous piece with the holder 4 .

[0122] While pre-configuring components of a device based on static impedance values ​​can reduce device complexity, it can also inadvertently reduce process efficiency. To clarify, device components such as transmission lines have a Q factor (quality factor) associated with them that represents the strength of damping of wave oscillations caused by power loss mechanisms. Fig.10 The possible effect of the Q factor on the resonant frequency bandwidth is shown. Specifically, the higher the Q factor, the narrower the bandwidth ( Fig.10 The peak value in 1), while the lower the Q factor, the wider the bandwidth ( Fig.102). A narrower resonant curve means that a device configured with a higher Q factor will require less power to treat weeds than a device with a lower Q factor. However, in order to maintain such a high Q factor, the impedance matching conditions need to be adjusted to the specific impedance factor of the weed being treated, which is possible in a laboratory environment when focusing on a single weed type, but is impractical when using the device in a field where multiple different weeds are growing.

[0123] There are configurations that allow minimizing or preventing changes in the Q factor at the receiver and transmitter sides. On the transmitter side, the device can be configured to minimize the reflection of microwaves. For example, a shield can be provided for the shape of the antenna so that the reflected waves are blocked. On the other hand, the device can be configured to maximize the absorption of microwaves by optimizing the absorption curve. However, as discussed previously, such a configuration may be too complex for a single pre-configured impedance value. However, this limitation can be overcome by changing the resonant frequency peak to a higher / lower frequency at the microwave generator to implement a variable impedance value. Specifically, as Fig.10 As further indicated by the dashed arrow, since the bandwidth broadening (peak 2) is the result of quality loss, the narrow bandwidth can be maintained by changing the microwave frequency whenever a decrease in the Q factor is detected. This solution can be implemented as a dynamic adjustment of the emitted microwave frequency based on the detected reflection curve of the treatment area. Dynamic microwave frequency adjustment is considered a preferred embodiment of the device, and the actual implementation of this technology will be further described below in the present disclosure.

[0124] In an embodiment, the antenna system is configured so that the electromagnetic field generated in the treatment area is strong enough so that the time span to reach the predetermined temperature of the treatment area is as short as possible, preferably less than 10s. This speed is conducive to treating weeds at average walking speed.

[0125] Preferably, the device of the present invention is additionally provided with a feedback unit, which is configured to intervene in the operation of the device when the impedance of the treatment area deviates from a standard operating impedance value, which preferably corresponds to a free space value of 377 ohms. This may occur, for example, when the device is directed at a substance with a higher impedance value than plants, such as at the body of a person or an animal. As discussed above, in the case of different impedance values, the transmitted wave will be partially reflected back to the antenna system, as a result of which the reflected wave will interfere with the transmitted wave and change the standing wave ratio. By measuring the standing wave ratio (usually expressed as reflection coefficient Γ), the reflectivity can be determined. Therefore, the feedback unit can, for example, be used as a safety measure to prevent accidents and / or an efficiency measure for ensuring treatment efficiency, as will be further described below.

[0126] In an embodiment, the feedback unit may be configured to act as a safety measure by preventing microwaves from being emitted from the device whenever the presence of non-plant matter is detected in the area to be treated. As discussed above, the impedance value of non-plant organic matter (such as the body of a human or animal) will be very different from plant tissue, which can be determined based on the standing wave ratio principle discussed above. Obviously, the same principles apply when the device is pointed at inorganic or reflective materials (such as metals), which may potentially compromise safety by reflecting microwaves onto the user. Preferably, the emission of microwaves is prevented by reducing the power of the microwave generator to a harmless power level (i.e., harmless to the user), turning off the generator and / or mechanically blocking the microwaves from being emitted from the antenna system, for example by providing a slidable cover on the antenna system or within other components of the device such as a transmission line.

[0127] In an embodiment, the feedback unit may be configured to function as an efficiency measure by dynamically adjusting one or more operating parameters of the microwave generator whenever a decrease in the Q factor is determined during treatment. As discussed above, different plant types and / or growth stages will have slightly different impedance values ​​corresponding to different resonant frequencies. Changes in the resonant frequency may affect the resonant frequency bandwidth, resulting in a widening such that more power and / or time is required to treat the weeds. Therefore, by dynamically changing the microwave frequency to correspond to the impedance value of the weeds in the treatment area, a narrow resonant frequency bandwidth may be maintained to ensure efficient treatment. Therefore, a preferred embodiment is that the feedback unit dynamically adjusts the frequency of the microwaves generated by the microwave generator to correspond to the resonant frequency of the treatment area.

[0128] In a preferred embodiment, the feedback unit can be configured to act as a safety and efficiency measure by dynamically adjusting one or more operating parameters of the microwave generator, in particular changing the microwave frequency when the characteristics of the processing area remain within a predefined safe operating range and preventing microwave emission when the characteristics exceed a predefined safe operating threshold. The characteristics of the processing area can be determined based on one or more parameters of the standing wave ratio principle discussed above, including wave reflection, standing wave ratio, reflection coefficient and / or impedance value. The actual implementation of these embodiments will be described below.

[0129] In one embodiment, the feedback unit can be configured to intervene by preventing the emission of microwaves with a wave reflection higher than 30% or 35%, preferably higher than 40% or 45%, still more preferably 50% or 55%, still more preferably 60% or 65%, still more preferably 70% or 75%, for example 80%, 85%, 90%, 95% or 100%.

[0130] In one embodiment, the feedback unit can be configured to intervene by blocking the emission of microwaves having a standing wave ratio higher than 5.0 or 5.5, preferably higher than 6.0 or 6.5, still more preferably higher than 7.0 or 7.5, still more preferably higher than 8.0 or 8.5 (e.g. 9.0, 9.5 or 10).

[0131] In one embodiment, the feedback unit may be configured to intervene by blocking the emission of microwaves having a reflection coefficient lower than 0.95 or 0.9, preferably lower than 0.85 or 0.8, such as 0.75, 0.7, 0.65 or 0.6.

[0132] In one embodiment, the feedback unit can be configured to intervene by dynamically adjusting the microwave parameters at which the wave reflection is below 30% or 35%, preferably below 40% or 45%, still more preferably 50% or 55%, still more preferably 60% or 65%, still more preferably 70% or 75%, for example 80%, 85%, 90%, 95% or 100%.

[0133] In one embodiment, the feedback unit may be configured to intervene by dynamically adjusting microwave parameters at a standing wave ratio below 5.0 or 5.5, preferably 6.0 or 6.5, still more preferably below 7.0 or 7.5, still more preferably below 8.0 or 8.5 (e.g. 9.0, 9.5 or 10).

[0134] In one embodiment, the feedback unit may be configured to intervene by dynamically adjusting microwave parameters having a reflection coefficient higher than 0.95 or 0.9.0, preferably higher than 0.85 or 0.80, such as 0.75, 0.70, 0.65 or 0.60.

[0135] The configuration of the feedback unit described previously was found to be suitable for accurately distinguishing substances with impedance values ​​of 50 ohms or more (such as human or animal bodies) or plant tissues without experiencing undesirable interruptions due to other objects or substances that may be located in the area to be treated. However, those skilled in the art therefore understand that the configuration of the feedback unit can be adjusted according to the desired safety.

[0136] According to one embodiment of the feedback unit, an integrated detection and control unit may be used in the generator in the device of the invention, which has this option and which may be suitably arranged so that when the detected impedance changes, the generator automatically switches off or reduces the power. When the control unit forms an integral part of the generator, the integrated control unit for controlling the feedback unit may itself form part of the control unit of the device.

[0137] However, the control unit of the device itself may also be a separate component connected to the generator and to one or more input means and / or indicators, such as operating buttons or LEDs on the handle of the holder. The control unit of the device may also consist of a plurality of interconnected control units, such as a control unit forming part of the generator and controlling the feedback unit, and a separate control unit connected to the generator and to operating means and / or indicators intended for a user of the device. The feedback unit may thus also be connected to a warning system which informs the user of a possible problem, for example via an acoustic signal or light.

[0138] Yet another embodiment of the feedback unit comprises an antenna system provided with an impedance adapter which cannot be adjusted manually, but comprises an automatic adjustment system which can be controlled using electrical control signals. As described above, the automatic adapter is then connected to the control unit of the feedback unit. When the control unit determines that the deviation of the impedance is too great, the impedance can be adjusted by sending a control signal to the automatic adapter so that the determined target value is maintained, or so that the "impedance matching" may be temporarily interrupted. This can replace or supplement the automatic control of the generator by the feedback unit.

[0139] In the embodiment shown, a roller system is attached to the second coupling flange 25 in the form of an angle plate 28, wherein two wheels 29 are attached to the ends. The wheels 29 rest on the ground and allow the holder 4 to roll on the ground. In this way, when the holder 4 is kept at an angle that deviates very little from the average, the distance between the outlet 27 and the ground remains more or less constant. However, the present invention is not limited to a holder provided with such a roller system. According to another embodiment, the holder 4 does not rest on the ground, and the user himself determines the distance of the ground from which the outlet 27 of the antenna 24 moves.

[0140] Figure 6 An alternative embodiment is shown in which the transmission line 2 is partially incorporated into the holder 4, in this case the holder comprises a hollow stem. The transmission line 2 is preferably also a coaxial cable, consisting of a first portion extending from the microwave generator 14 to the holder 4 and a second portion contained in the hollow stem of the holder 4. The first portion is long enough to enable all necessary manipulations of the stem. The antenna system 3 can be arranged in a manner similar to that of the antenna system 3, except that the signal adapter 20 may not have lateral connections but connections parallel to the holder. Figure 4 or Figure 5In any embodiment of the device, the portable part 1 may additionally be provided with means for charging the battery 12. These means may consist of a port into which a charger cable may be inserted. In a preferred embodiment, the portable part 1 may include one or more solar cells attached to the housing 10 or incorporated into the material of the housing 10 (e.g. a textile), so that the battery can be optionally recharged during use of the device.

[0141] According to another embodiment of the device, the power supply may include a cable connected to an external power source. The power supply may consist of a port into which a power cable connected to the external power source may be inserted and a device configured for transmitting electrical energy, by which the energy of the power source is adjusted to the power requirement of the microwave generator (e.g. a transformer). The external power source may be, for example, a portable generator placed in a field near the area to be treated, or alternatively directly connected to the grid.

[0142] In any embodiment of the device, the holder 4 may additionally be provided with a user interaction panel, preferably provided with indicators, such as green and red LEDs, which indicate when sufficient energy has been delivered to a given part of the treated plant. These indicators are controlled by the control unit of the device based on various parameters, which may include the power and frequency of the generator 14 or input data entered by the user. Preferably, there are also indicators on the holder 4, which indicate to what extent the battery is charged and / or how much charge is left.

[0143] According to one embodiment, the device is provided with a temperature sensor arranged on the microwave generator 14, the temperature sensor preferably being a spectrum sensor connected to a control unit of the device, and wherein the control unit is configured to adjust the operation of the microwave generator based on the measured spectrum, preferably by switching off the microwave generator when a predetermined temperature threshold is exceeded. The spectrum sensor may be an infrared sensor.

[0144] Another aspect of the present disclosure relates to a feedback unit for use in an apparatus for treating weeds by microwaves. It will be appreciated that the feedback unit discussed above and any of its embodiments may be independently applied to an apparatus having a configuration different from that of the portable apparatus described above. In particular, the feedback unit (advantageously in the form of an integrated control unit) may be applied to an apparatus whereby the microwave generator does not need to be included in the portable part and / or the microwave emitter does not need to be attached to a holder. However, in order to avoid repetition in writing, reference is made to the principles and practical implementations of the feedback unit as described above. Unless otherwise stated, it will be appreciated that all embodiments of the feedback unit when applied to the portable apparatus described above also form embodiments of the feedback unit when applied to an apparatus of a different configuration.

[0145] Another aspect of the present disclosure relates to an apparatus for treating weeds by microwaves, wherein the apparatus comprises the following components:

[0146] - a microwave generator and a power supply arranged to supply power to said generator;

[0147] - an antenna system configured to direct the microwaves to the area to be treated,

[0148] - optionally, a transmission line or waveguide configured to transmit microwaves from the microwave generator to the antenna system; and

[0149] - a control unit operatively connected to or forming part of the microwave generator; wherein the control unit is configured to detect a change in the impedance of the treatment area outside a predetermined range around an expected value of the impedance and to intervene in the operation of the device upon detection of said change.

[0150] In an embodiment, the control unit may be configured to act as a safety measure by preventing microwaves from being emitted from the device whenever the presence of non-weed organic matter and / or inorganic matter is detected in the area to be treated; preferably by reducing the power of the microwave generator to a harmless level, switching off the generator and / or mechanically blocking microwaves from being emitted from the antenna system.

[0151] In an embodiment, the control may be configured to act as an efficiency measure by dynamically adjusting one or more operating parameters of the microwave generator whenever a reduction in the Q factor is determined; preferably by adjusting the microwave frequency to correspond to the resonant frequency of the treatment zone.

[0152] In an embodiment, the device may include or be arranged on a vehicle, preferably an autonomous vehicle (AV), which may benefit from the same advantageous safety measures against accidents and / or efficiency measures to ensure treatment efficiency when moving the device over the area to be treated, as previously discussed for the device in the portable embodiment.

Claims

1. A device for treating weeds by microwaves, characterized in that The device comprises the following components: a portable part (1) configured to be fixed to the body of a user; wherein the portable part comprises a housing (10) in which a microwave generator (14) is arranged and a power supply for supplying power to the microwave generator (14); - a holder (4) provided with at least two ends, wherein the holder can be held by the user via one end, and wherein an antenna system (3) is attached to the other end, the antenna system being configured to guide microwaves into the area to be treated (30); - a transmission line (2) configured to transmit the microwaves from the microwave generator (14) to the antenna system (3).

2. The device according to claim 1, wherein: The antenna system (3) comprises the following components arranged one after the other: - a signal adapter (20) for converting the signal from the transmission line (2) into microwaves, - a waveguide (23), and -An antenna (24) or a group of antenna elements.

3. The device according to claim 2, wherein: The waveguide (23) is an impedance adapter, the impedance of which can be adjusted manually or automatically so that almost no reflection occurs at the transition between the antenna (24) or the antenna element group and the area to be treated (30).

4. The device according to claim 2, wherein: The impedance of the waveguide is configured so that when the impedance of the area to be treated is within a predetermined range around a value of 377 ohm, almost no reflection occurs at the transition between the antenna (24) or the antenna element group and the area to be treated (30).

5. The device according to claim 3, wherein: The impedance of the waveguide is configured so that when the impedance of the area to be treated is within a predetermined range around a value of 377 ohm, almost no reflection occurs at the transition between the antenna (24) or the antenna element group and the area to be treated (30).

6. The device according to any one of claims 2 to 5, wherein: The antenna (24) has an entrance portion coupled to the signal adapter (20) or the waveguide (23), and a slot-shaped exit portion (27) along which the microwaves are guided to the outside.

7. The apparatus according to any one of claims 1 to 5, further comprising a control unit operatively connected to the microwave generator (14) or forming part of the microwave generator and configured to control the operation of the microwave generator based on (i) input from the user, (ii) detected information about the area to be processed (30), and / or (iii) Detected information about the operation of the device itself.

8. The device according to claim 7, further comprising a temperature sensor connected to the control unit, and wherein The control unit is configured to adjust operation of the microwave generator based on the measured temperature.

9. The device according to claim 8, wherein: The temperature sensor is arranged on the microwave generator (14).

10. The device according to claim 8, wherein: The control unit is configured to switch off the microwave generator when the measured temperature exceeds a predetermined threshold.

11. The device according to claim 7, further comprising a feedback unit, the feedback unit being configured to detect a change in the impedance of the area to be treated (30) beyond a predetermined range around an expected value of the impedance, and to intervene in the operation of the device when the change is detected.

12. The device according to claim 11, wherein The feedback unit is configured to act as a safety measure by preventing microwaves from being emitted from the device whenever the presence of non-weed organic matter and / or inorganic matter is detected in the area to be treated.

13. The device according to claim 12, wherein: The feedback unit is configured to act as a safety measure by reducing the power of the microwave generator (14) to a harmless level, switching off the microwave generator (14) and / or mechanically blocking the microwaves from being emitted from the antenna system (3).

14. The apparatus according to claim 12 or 13, wherein: The feedback unit is configured to measure and / or determine wave reflection, standing wave ratio and / or reflection coefficient and to prevent microwave emission in the following situations - said wave reflection is lower than or equal to 30%, - the standing wave ratio is lower than or equal to 8, and / or - said reflection coefficient is higher than or equal to 0.

8.

15. The device according to any one of claims 11 to 13, wherein: The feedback unit is configured to function as an efficiency measure by dynamically adjusting one or more operating parameters of the microwave generator whenever a decrease in the Q factor is determined.

16. The device according to claim 15, wherein: The feedback unit is configured to act as an efficiency measure by adjusting the microwave frequency during treatment to correspond to the resonance frequency of the area (30) to be treated.

17. The apparatus according to claim 15, wherein: The feedback unit is configured to measure and / or determine wave reflection, standing wave ratio and / or reflection coefficient, and to dynamically adjust one or more operating parameters of the device in the event of - said wave reflection is higher than or equal to 30%, - the standing wave ratio is higher than or equal to 8, and / or - said reflection coefficient is lower than or equal to 0.

8.

18. The device according to any one of claims 1-5, 8-13 and 16-17, wherein: The microwave generator (14) is a solid-state microwave generator.

19. The device according to any one of claims 1-5, 8-13 and 16-17, wherein: The portable part (1) comprises a power source (12).

20. The apparatus of claim 19, wherein: The power source is a rechargeable and / or replaceable battery.

21. The apparatus according to any one of claims 1-5, 8-13, 16-17 and 20, wherein: The portable part (1) comprises a cooling element for cooling the microwave generator (14) and / or a power supply (12) of the portable part (1).

22. The apparatus according to any one of claims 1-5, 8-13, 16-17 and 20, wherein: The portable part (1) comprises a port for connecting a power cable connected to an external power source, and means for transmitting electrical energy, by means of which the energy of the power source is adjusted to the power requirement of the microwave generator (14).

23. The apparatus of claim 22, wherein: By means of the device for transmitting electrical energy, the energy of the power source is adjusted to the power requirement of the transformer.

24. The apparatus of any one of claims 1-5, 8-13, 16-17, 20 and 23, wherein: The holder (4) is in the shape of an elongated handle, a first end of which is provided with a grip for the user, and the other end of which is connected to the antenna system (3).

25. The apparatus of claim 24, wherein: The handle is provided with an input device for the user and / or is provided with an indicator to provide the user with information about the treatment of the area to be treated (30).

26. The apparatus of any one of claims 1-5, 8-13, 16-17, 20 and 23, wherein: The holder (4) is provided with a hollow channel, and wherein a portion of the transmission line (2) and / or the waveguide (23) of the antenna system (3) is located in the hollow channel.

27. The apparatus of any one of claims 1-5, 8-13, 16-17, 20 and 23, wherein: The antenna system (3) and / or the holder (4) are provided with a roller system (28, 29), by means of which the user can roll the holder (4) on the ground during the treatment of the area (30) to be treated.

28. A method for treating weeds by microwaves using a device according to any one of claims 1 to 27, the method comprising: (a) generating microwaves using a microwave generator; (b) directing the generated microwaves toward the area to be treated (30); (c) determining the impedance value of the area to be treated by measuring wave reflection, standing wave ratio and / or reflection coefficient; (d) Continue to guide the generated microwaves under the following conditions: - wave reflection is less than or equal to 30%, - Standing wave ratio less than or equal to 8, and / or -Reflection coefficient greater than or equal to 0.

8.

29. The method according to claim 28, wherein: Step (d) includes stopping directing the generated microwaves when - wave reflection higher than 30%, - Standing wave ratio higher than 8, and / or -Reflectance coefficient is less than 0.

8.

30. The method according to claim 28 or 29, further comprising: (e) whenever a decrease in the Q factor is determined, adjusting one or more operating parameters of the microwave generator.

31. The method according to claim 30, wherein: Step (e) comprises dynamically adjusting the microwave frequency to correspond to the resonant frequency of the area (30) to be treated during treatment.

32. Use of a device according to any one of claims 1 to 27 for treating weeds.

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