Aerosol-generating device with radio frequency energy harvesting system

Abstract

The invention relates to an aerosol-generating device. An aerosol-generating device includes a body having a housing and a heating element. A heating element is disposed within the housing. The aerosol-generating device also includes one or both of a power source and a secondary electrical device. The aerosol-generating device also includes a radio frequency energy harvesting system. The radio frequency energy harvesting system is configured to harvest electromagnetic energy from electromagnetic radiation. The radio frequency energy harvesting system is configured to one or both of recharge a power source and power a secondary powered device. The secondary powered device comprises means for sending location information from the aerosol-generating device. The invention also relates to a charger for an aerosol-generating device. The charger includes a charger power source. The charger is configured to emit radio frequency electromagnetic radiation whose frequency is optimized for energy transfer to a radio frequency energy harvesting system of the aerosol-generating device.

Description

Technical Field

[0001] The present invention relates to an aerosol generating device. The present invention relates to an aerosol generating system. The present invention relates to a charger for an aerosol generating device. The present invention relates to a system comprising an aerosol generating device and a charger. Background Art

[0002] There are known aerosol generating devices for generating an inhalable vapor. Such devices can heat an aerosol-forming substrate to a temperature at which one or more components of the aerosol-forming substrate are volatilized, without burning the aerosol-forming substrate. The aerosol-forming substrate can be provided as part of an aerosol-generating article. The aerosol-generating article can have a strip shape for inserting the aerosol-generating article into a chamber (such as a heating chamber) of the aerosol generating device. A heating element can be arranged in or around the heating chamber for heating the aerosol-forming substrate once the aerosol-generating article is inserted into the heating chamber of the aerosol generating device. Summary of the Invention

[0003] Aerosol generating devices are typically powered by a rechargeable battery. In order to recharge the battery, the aerosol generating device typically has to be connected to a power plug or a charger. During battery recharging, the aerosol generating device is typically not available for use. This can prevent or delay the desired use of the aerosol generating device. Accordingly, the user needs to plan and schedule when and where to recharge their device.

[0004] There is a desire to have an aerosol generating device with improved battery life. There is a desire to have an aerosol generating device with improved energy efficiency. There is a desire to have an aerosol generating device with improved energy supply to a secondary system.

[0005] According to an embodiment of the present invention, there is provided an aerosol generating device. The aerosol generating device includes a body having a housing and a heating element. The heating element is arranged within the housing. The aerosol generating device further includes one or both of a power source and a secondary electrical device. The aerosol generating device further includes a radio frequency energy harvesting system. The radio frequency energy harvesting system is configured to harvest electromagnetic energy from electromagnetic radiation. The radio frequency energy harvesting system is configured to perform one or both of the following operations: recharge the power source and power the secondary electrical device.

[0006] According to an embodiment of the present invention, an aerosol generating device is provided. The aerosol generating device may include a main body having a housing and a heating element. The heating element may be disposed within the housing. The aerosol generating device may further include one or both of a power source and a secondary electrical device. The aerosol generating device may further include a radio frequency energy harvesting system. The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from electromagnetic radiation. The radio frequency energy harvesting system may be configured to perform one or both of the following operations: recharge the power source and power the secondary electrical device.

[0007] By providing an aerosol generating device including a radio frequency energy harvesting system, a device with improved battery life can be provided. By providing an aerosol generating device including a radio frequency energy harvesting system, a device with improved energy efficiency can be provided. By providing an aerosol generating device including a radio frequency energy harvesting system, a device with improved energy supply to the secondary system can be provided.

[0008] Radio frequency energy harvesting is a technology that provides the generation of electrical energy from ambient / surrounding radio frequency signals. This energy can be used to generate direct current. Ambient / surrounding radio frequency signals are, for example, Wi-Fi and wireless networks, signals from mobile phones or television stations.

[0009] The radio frequency energy harvesting system may include one or both of a radio frequency energy harvesting circuit, an impedance matching circuit, a rectifier circuit, and a storage unit. The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from ambient electromagnetic radiation. The ambient electromagnetic radiation may be signals from Wi-Fi and wireless networks, mobile phones, or television stations.

[0010] The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from electromagnetic radiation in a frequency range between 0.8 GHz and 60 GHz, preferably between 0.8 GHz and 6 GHz. The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from electromagnetic radiation having one or both of the frequencies 2.4 GHz and 5 GHz.

[0011] The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from ambient electromagnetic radiation in a frequency range between 0.8 GHz and 60 GHz, preferably between 0.8 GHz and 6 GHz. The radio frequency energy harvesting system may be configured to harvest electromagnetic energy from ambient electromagnetic radiation having one or both of the frequencies 2.4 GHz and 5 GHz.

[0012] The power source may include a battery. The power source may be a lithium-ion battery. Alternatively, the power source may be a nickel-metal hydride battery, a nickel-cadmium battery, or a lithium-based battery, such as a lithium cobalt, lithium iron phosphate, lithium titanate, or lithium polymer battery.

[0013] The body may include a cavity configured to receive an aerosol-generating article or a cartridge containing an aerosol-forming substrate. The cavity may be at least partially surrounded by a heating element. The cavity may be a heating chamber. The cavity may have an opening. The opening may be at the proximal end of the body.

[0014] The heating element may be an inductive heating element. The heating element may include at least one inductor coil. The inductor coil may be arranged at least partially around the heating chamber of the body. Alternatively, the heating element may include a resistive heating element.

[0015] The housing may be elongate. The housing may include any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics, or composite materials containing one or more of these materials, or thermoplastics suitable for food or pharmaceutical applications, such as polypropylene, polyetheretherketone (PEEK), and polyethylene. Preferably, the material is lightweight and not easily breakable. The housing may include a user interface for activating the aerosol-generating device, for example, a button for initiating heating of the aerosol-generating device or a display for indicating the status of the aerosol-generating device or the aerosol-forming substrate.

[0016] The aerosol-generating device may include a primary electrical device and a secondary electrical device. The primary electrical device may be the heating element. The primary electrical device may require at least 5 to 20 times more energy than the secondary electrical device, preferably at least 10 to 15 times more energy than the secondary electrical device.

[0017] The secondary electrical device may be partially powered by a radio frequency energy harvesting system. The secondary electrical device may be powered only by the radio frequency energy harvesting system. By powering the secondary electrical device only by the radio frequency energy harvesting system, the electrical connection from the power source to the secondary electrical device can be omitted.

[0018] The secondary electrical device may include a sensor. The secondary electrical device may be a sensor. The sensor may include a capacitance sensor. The capacitance sensor may be configured to detect whether a user is holding the aerosol-generating device.

[0019] The secondary electrical device may include a device for sending out the location information of the aerosol-generating device. Thus, even when the power source is depleted, the aerosol-generating device can be located. The device for sending out the location information may be configured to emit a radio frequency signal, preferably a backscattered radio frequency signal. The backscattered radio frequency signal may include a unique identifier. The location of the aerosol-generating device may be located via a smartphone. The location of the aerosol-generating device may be located via a charger for charging the aerosol-generating device.

[0020] The secondary power consumer may include a charging indicator, preferably an optical charging indicator. The secondary power consumer may include one or both of a device for sending position information from the aerosol generating device and a charging indicator, preferably an optical charging indicator. The secondary power consumer may include a charging indicator and a capacitive sensor. The optical charging indicator may include an LED. The charging indicator may include a speaker. The secondary power consumer may be a charging indicator. The charging indicator may include a low battery indicator. The low battery indicator may warn the user when the battery level is low. The low battery indicator may indicate when the battery charge is below a certain battery charge, for example below 20% or below 10% or below 5%. The warning may be a specific periodic or persistent signal. The periodic or persistent signal may be a light signal or an acoustic signal. The signal itself may draw power from the battery, so the low battery may be further consumed. Further consumption of the low battery may be prevented by powering the charging indicator by a radio frequency energy harvesting system.

[0021] The aerosol generating device may further comprise a controller. The controller may be configured to control the radio frequency energy harvesting system to recharge the power supply if the controller detects that the power supply is not fully charged. The controller may be configured to control activation of the puff sensor if the capacitive sensor detects that the user is holding the aerosol generating device. The controller may comprise a processor. The controller may be a processor. The processor may cause a retroactive action during or after processing the signal.

[0022] The controller may be configured to control activation of the optical charge indicator if the power level of the power source is below 50%, preferably below 40%, more preferably below 30%, most preferably below 20%.

[0023] The radio frequency energy collection system may include an antenna. The antenna may be a transducer device. The antenna may convert ambient radio frequency into alternating current (AC). The antenna may be arranged to be embedded in the housing of the aerosol generating device or applied to the interior of the housing of the aerosol generating device or directly adjacent to the housing of the aerosol generating device. The housing may include an antenna. The housing may be an antenna. The antenna may be arranged at least partially around the cavity of the body. The antenna may extend over at least 60%, preferably at least 70%, more preferably at least 80%, and most preferably at least 85% of the length of the housing of the aerosol generating device. The length of the housing may be measured in a direction along the longitudinal axis of the aerosol generating device. At least one induction coil may be an antenna. Preferably, at least one induction coil may be a flat induction coil, which is an antenna.

[0024] The secondary power-consuming device may include a capacitance sensor. The capacitance sensor may detect contact of a user's hand or lip on the body of the aerosol-generating device. In the case where the capacitance sensor detects the contact, the radio frequency energy harvesting system may send a "wake-up" signal to the controller, and then the controller activates the draw sensor or increases the sampling frequency of the draw sensor.

[0025] In one embodiment, the aerosol-generating device may include a draw sensor, a battery, a capacitance sensor, a radio frequency energy harvesting system, and a controller. The draw sensor, the battery, the capacitance sensor, and the radio frequency energy harvesting system are all connected to the controller. The draw sensor may be bidirectionally connected to the controller. The capacitance sensor and the battery may be connected to the controller to allow data transmission towards the controller. The radio frequency energy harvesting system may additionally be connected to the capacitance sensor, thus allowing data transmission from the radio frequency energy harvesting system towards the capacitance sensor. Both the battery and the low battery indicator may be connected to the radio frequency energy harvesting system, thus allowing data transmission from the radio frequency energy harvesting system towards them respectively.

[0026] The radio frequency energy harvesting system may provide a primary task and a secondary task. The primary task of the radio frequency energy harvesting system may be to continuously recharge the power source. When the aerosol-generating device is not in operation, the radio frequency energy harvesting system may recharge the power source. The secondary task of the radio frequency energy harvesting system may be to power a secondary power-consuming device. The secondary power-consuming device may include one or both of a capacitance sensor and a charging indicator (preferably a capacitance sensor and a low battery indicator).

[0027] If the battery is completely depleted, the radio frequency energy harvesting system may recharge the power source. If the battery level is low, such as below 20%, 15%, or 10% of the battery level, the radio frequency energy harvesting system may recharge the power source. If the battery level is not full, the radio frequency energy harvesting system may recharge the power source.

[0028] The body may include a charging port. The charging port may be located at a distal end of the body. The charging port may be configured to charge the aerosol-generating device. Additionally or alternatively, the charging port may be configured to transmit data between the aerosol-generating device and an external electronic device (such as a mobile phone).

[0029] The present invention further relates to an aerosol generating system, which comprises an aerosol generating device and an aerosol generating article. The aerosol generating article may comprise an aerosol-forming substrate. The aerosol generating article may be a strip-shaped article. The aerosol generating device may comprise a cavity configured to receive the aerosol generating article. The aerosol generating article may be partially inserted into the cavity of the aerosol generating device. The aerosol generating article may comprise a filter portion and an aerosol-forming substrate portion. When the aerosol generating article is inserted into the cavity of the aerosol generating device, a user may draw on the filter portion of the aerosol generating article. The heating element may comprise at least one inductor coil, and the aerosol generating article may comprise a susceptor material.

[0030] The present invention further relates to a charger for an aerosol generating device as described herein. The charger may comprise a charger power source. The charger may be configured to emit radio frequency electromagnetic radiation whose frequency is optimized for energy transfer to a radio frequency energy harvesting system of the aerosol generating device. The charger may comprise a radio frequency transmitter.

[0031] The charger may be a mobile charger. The charger may further comprise a charger radio frequency energy harvesting system configured to recharge the charger power source.

[0032] The present invention also relates to a system comprising an aerosol generating device as described herein and a charger. The secondary electrical device of the aerosol generating device may comprise means for sending out location information. The charger may be configured to emit a radio frequency search signal. The means for sending out location information may be configured to emit a backscattered radio frequency signal when a radio frequency search signal is detected. The charger may be configured to perform one or both of the following operations when a backscattered radio frequency signal is detected: identify the aerosol generating device and locate the aerosol generating device. Thus, if the aerosol generating device is lost in the area around the user when the battery runs out, the user may find the aerosol generating device. The charger may comprise at least one proximity LED, preferably a plurality of proximity LEDs. The location of the aerosol generating device may be detected by the charger based on the weakening of the detected backscattered radio frequency signal. The proximity LED may indicate the location of the aerosol generating device, for example, by the intensity of the optical signal and / or by changing the light pattern of the plurality of proximity LEDs.

[0033] As used herein, the term "proximal" refers to the user end or mouth end of the aerosol generating device or system or a part thereof, and the term "distal" refers to the end opposite the proximal end. When referring to the heating chamber, the term "proximal" refers to the region closest to the open end of the cavity, and the term "distal" refers to the region closest to the closed end.

[0034] As used herein, the term "aerosol-forming substrate" refers to a substrate capable of releasing volatile compounds that can form an aerosol or vapor. Such volatile compounds can be released by heating the aerosol-forming substrate. The aerosol-forming substrate can be in solid form or can be in liquid form. The terms "aerosol" and "vapor" are used synonymously.

[0035] The aerosol-forming substrate can include nicotine. The nicotine-containing aerosol-forming substrate can be a nicotine salt substrate.

[0036] The aerosol-forming substrate can include plant-based materials. The aerosol-forming substrate can include tobacco. The aerosol-forming substrate can include tobacco-containing materials that include volatile tobacco flavor compounds released from the aerosol-forming substrate upon heating. Alternatively, the aerosol-forming substrate can include non-tobacco materials. The aerosol-forming substrate can include homogenized plant-based materials. The aerosol-forming substrate can include homogenized tobacco materials. The homogenized tobacco materials can be formed by coalescing particulate tobacco.

[0037] The aerosol-forming substrate can include at least one aerosol-forming agent. An aerosol-forming agent is any suitable known compound or mixture of compounds that promotes the formation of a dense and stable aerosol during use and is substantially thermally resistant to degradation at the operating temperature of the aerosol-generating system. Suitable aerosol-forming agents are well known in the art and include, but are not limited to: polyols such as triethylene glycol, 1,3-butanediol, and glycerol; esters of polyols such as glycerol mono-, di-, or triacetate; and aliphatic esters of mono-, di-, or polycarboxylic acids such as dimethyl dodecanedioate and dimethyl tetradecanedioate. Preferred aerosol-forming agents are polyols or mixtures thereof such as triethylene glycol, 1,3-butanediol. Preferably, the aerosol-forming agent is glycerol. If present, the aerosol-forming agent content of the homogenized tobacco materials can be equal to or greater than 5% by weight on a dry weight basis, and preferably is 5% to 30% by weight on a dry weight basis. The aerosol-forming substrate can include other additives and ingredients such as flavorants.

[0038] As used herein, a "sensor" or "sensor element" refers to an element that heats up when subjected to an alternating magnetic field. This can be due to eddy currents induced in the sensor element, hysteresis losses, or both eddy currents and hysteresis losses. During use, the sensor element is positioned in thermal contact or close thermal proximity to the aerosol-forming substrate received in the aerosol-generating article or cartridge. In this way, the aerosol-forming substrate is heated by the sensor such that an aerosol is formed.

[0039] The power source may need to be recharged and may have a capacity enabling sufficient energy to be stored for one or more usage experiences; for example, the power source may have sufficient capacity to continuously generate aerosol for a period of about six minutes or a multiple of six minutes. In another example, the power source may have sufficient capacity to provide a predetermined number of puffs or discontinuous activations of the heating element.

[0040] The power source may be a direct current (DC) power source. In one embodiment, the power source is a DC power source having a DC supply voltage in the range of 2.5 volts to 4.5 volts and a DC supply current in the range of 1 ampere to 10 amperes (corresponding to a DC power source in the range of 2.5 watts to 45 watts). The aerosol generating device may advantageously include a direct current to alternating current (DC / AC) inverter for converting the DC current supplied by the DC power source into an alternating current. The DC / AC converter may include a class D, class C, or class E power amplifier. The AC power output of the DC / AC converter is supplied to the induction coil.

[0041] Features described with respect to one embodiment may equally apply to other embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The present invention will be further described by way of example only with reference to the accompanying drawings, in which:

[0043] Figure 1 A radio frequency energy harvesting system is shown;

[0044] Figure 2A A 3D view of the aerosol generating device is shown, Figure 2B A cross-sectional view of the aerosol generating device is shown;

[0045] Figure 3 The interaction of the electronic components of the aerosol generating device is shown;

[0046] Figure 4 A flowchart depicting an algorithm used by the aerosol generating device is shown;

[0047] Figure 5 A charger for the aerosol generating device is shown, and

[0048] Figure 6 A system including the aerosol generating device and the charger is shown. DETAILED DESCRIPTION

[0049] In Figure 1In it, the general working principle of a radio frequency energy harvesting system is shown. Ambient radio frequency signals 10 (such as, for example, Wi-Fi and wireless networks, signals from mobile phones or television stations) are radiated onto a radio frequency energy harvesting system 12 to generate a direct current (DC) 14. More specifically, the radio frequency energy harvesting system 12 includes an antenna 16, an impedance matching circuit 18, a rectifier circuit 20, and a storage unit 22. The antenna 16 is a transducer device that captures the ambient radio frequency signal 10 and converts it into an alternating current (AC) 24. The impedance matching circuit 18 adjusts the load impedance to the source 10. Thus, the maximum power can be transferred from the antenna 16 to the load. The rectifier circuit converts the AC 24 into DC 14. The storage unit 22 can be a capacitor. When no external energy is available, the storage unit 22 can store electricity to act as a power reserve device.

[0050] Figure 2A A 3D diagram of an aerosol generating device 26 including a body and an aerosol generating article 28 is shown. The aerosol generating article 28 includes a substrate portion (not shown) containing an aerosol forming substrate, and a mouthpiece portion 30. The body of the aerosol generating device 26 includes a user interface 32 that is a button. Figure 2B A cross-sectional view of the aerosol generating device 26 is shown. The device includes a cavity 34 into which the aerosol generating article 28 can be inserted. An inductor coil 36 is arranged at least partially around the cavity 34. The inductor coil 36 can heat a susceptor material (not shown) included in the aerosol generating article 28.

[0051] The aerosol generating device 26 further includes an antenna 16. The antenna 16 is embedded in a coating of the body of the aerosol generating device 26. The antenna 16 encapsulates a power source (which is a battery 38), a controller 40, a radio frequency energy harvesting system 12, and a charging port 40. Additionally, the charging port 40 can also be a data port. The controller 38 is connected via wiring to the battery 36, the radio frequency energy harvesting system 12, and the induction coil 36.

[0052] Figure 3 An interaction of the electronic components of the aerosol generating device 26 is shown. Figure 3 A manner in which the operation of the radio frequency energy harvesting system 12 can be organized according to the battery level of the aerosol generating device 26 is shown. Figure 3The various electronic components of the aerosol generating device 26 shown are a radio frequency energy harvesting system 12, a battery 36, a controller 38, a puff sensor 42, a capacitance sensor 44, and a charging indicator, the charging indicator being a low battery indicator 46. The low battery indicator 46 can be an LED or a speaker for indicating when the battery charge is below a certain battery charge level (such as below 20% or below 10% or below 5%). The radio frequency energy harvesting system 12 harvests ambient radio frequency signals 10. The arrows represent data transmission connections. The direction of the respective arrows shows the direction in which data can be transmitted.

[0053] The puff sensor 42, the battery 36, the capacitance sensor 44, and the radio frequency energy harvesting system 12 are all connected to the controller 38. The puff sensor 42 is bi-directionally connected. The capacitance sensor 44 and the battery 36 are connected to allow data transmission towards the controller 38. The radio frequency energy harvesting system 12 is additionally connected to the capacitance sensor 44, thus allowing data transmission from the radio frequency energy harvesting system 12 towards the capacitance sensor 44. Both the battery 36 and the low battery indicator 46 are connected to the radio frequency energy harvesting system 12, thus allowing data transmission from the radio frequency energy harvesting system 12 towards them respectively. The capacitance sensor 44 detects contact of the user's hand or lip on the body of the aerosol generating device 26. In the case where the capacitance sensor 44 detects contact, the radio frequency energy harvesting system 12 sends a "wake-up" signal to the controller 38, and the controller then activates the puff sensor 42 or increases the sampling frequency of the puff sensor 42. The low battery indicator 46 indicates whether the battery 36 is below a certain battery charge level.

[0054] The main task of the radio frequency energy harvesting system 12 is to continuously recharge the battery 36. The secondary task of the radio frequency energy harvesting system 12 is to power secondary electrical devices. Such secondary electrical devices can consist of one or both of the capacitance sensor 44 and the low battery indicator 46.

[0055] Figure 4 A flowchart depicting an algorithm that can be used by the aerosol generating device 26 including the radio frequency energy harvesting system 12 is shown. Starting at block 48, there is a question of whether the battery is completely depleted. If so, the radio frequency energy harvesting system 12 recharges the battery 50. If not, then at block 52, there is a question 52 of whether the battery charge is low. If the battery charge is low, the radio frequency energy harvesting system 12 recharges the battery 50. If the battery charge is not low, then at block 54 there is a question of whether the battery is full. If the battery charge is not full, the radio frequency energy harvesting system 12 recharges the battery 50.

[0056] Recharging the battery 50 is the main task 56 of the radio frequency energy harvesting system 12. The secondary task 58 of the radio frequency energy harvesting system 12 is to supply energy 60 to one or both of the low battery indicator and the capacitance sensor.

[0057] Figure 5 Shows a charger 62 for an aerosol generating device 26. The aerosol generating device includes the same components as discussed above. The charger 62 includes electronics 66, an antenna 68, and a radio frequency energy harvesting system 12. The charger 62 can transmit a radio frequency signal 10 to transfer energy to the aerosol generating device 26. Then, the transmitted radio frequency signal 10 can be converted by the radio frequency energy harvesting system 12 of the aerosol generating device to charge the battery 36 of the aerosol generating device 26. Thus, no connection is required and the aerosol generating device can still be used during charging.

[0058] The charger 62 can include a radio frequency energy harvesting system 12 that is self-connected to a battery 64. Thus, the charger can charge itself by using ambient radio frequency signals 10.

[0059] Figure 6 Shows a system including an aerosol generating device 70 and a charger 72. The aerosol generating device 70 includes the above-mentioned radio frequency energy harvesting system and a device (not shown) for sending out its location. The aerosol generating device 70 is located in a room of a fictional house depicted by a floor plan 74. The charger 72 includes a proximity LED 76. If the battery of the aerosol generating device 70 runs out, the user can send a radio frequency search signal 78 emitted by the charger. Even when the battery is depleted, the radio frequency energy harvesting system of the aerosol generating device 70 can utilize energy to power the device for sending out the location information of the aerosol generating device 70. When the radio frequency search signal 78 is detected by the aerosol generating device 70, the device for sending out the location information emits a backscattered radio frequency signal 80 to the charger. The backscattered radio frequency signal 80 includes a unique identifier. When the backscattered radio frequency signal 80 is detected, the charger 72 identifies the aerosol generating device 70. The localization of the aerosol generating device 70 can be detected by the charger 72 based on the weakening of the detected backscattered radio frequency signal 80. The proximity LED 76 can indicate the localization of the aerosol generating device 70, for example, by the intensity of the light signal and / or by changing the light pattern of the four LEDs 76.

Claims

1. An aerosol generating device, comprising: a body having a housing; a heating element, wherein the heating element is arranged within the housing; one or both of a power source and a secondary electrical device; and a radio frequency energy harvesting system, wherein the radio frequency energy harvesting system is configured to harvest electromagnetic energy from electromagnetic radiation, and wherein the radio frequency energy harvesting system is configured to perform one or both of the following operations: recharge the power source and supply power to the secondary electrical device, wherein the secondary electrical device includes means for sending out location information from the aerosol generating device.

2. The aerosol generating device according to claim 1, wherein the secondary electrical device includes a sensor, preferably wherein the sensor includes a capacitance sensor, and more preferably wherein the capacitance sensor is configured to detect whether a user is holding the aerosol generating device.

3. The aerosol generating device according to any one of the preceding claims, wherein the secondary electrical device includes a charging indicator, preferably an optical charging indicator, and more preferably wherein the optical charging indicator includes an LED.

4. The aerosol generating device according to any one of the preceding claims, wherein the electromagnetic radiation is preferably ambient electromagnetic radiation.

5. The aerosol generating device according to any one of the preceding claims, wherein the radio frequency energy harvesting system is configured to harvest electromagnetic energy from electromagnetic radiation having a frequency range between 0.8 GHz and 60 GHz, preferably between 0.8 GHz and 6 GHz, and more preferably from electromagnetic radiation having a frequency of one or both of 2.4 GHz and 5 GHz.

6. The aerosol generating device according to any one of the preceding claims, wherein the aerosol generating device further includes a controller.

7. The aerosol generating device according to the previous claim, wherein the controller is configured to control the radio frequency energy harvesting system to recharge the power source when the controller detects that the power source is not fully charged.

8. The aerosol generating device according to claim 2, wherein the controller is configured to control the activation of a puff sensor when the capacitance sensor detects that a user is holding the aerosol generating device.

9. The aerosol generating device according to the previous claim, wherein the puff sensor is configured as a secondary electrical device at least partially powered by the radio frequency energy harvesting system.

10. The aerosol generating device according to claim 3, wherein the controller is configured to control the activation of the optical charging indicator when the power level of the power source is below 50%, preferably below 40%, more preferably below 30%, and most preferably below 20%.

11. The aerosol generating device according to any one of the preceding claims, wherein the radio frequency energy harvesting system includes an antenna, and wherein the antenna is arranged to be embedded in the housing of the aerosol generating device or coated onto the interior of the housing or directly adjacent to the housing.

12. The aerosol generating device according to the preceding claim, wherein the antenna extends over at least 60%, preferably at least 70%, more preferably at least 80%, and most preferably at least 85% of the length of the housing of the aerosol generating device.

13. A charger for an aerosol generating device according to any one of the preceding claims, wherein the charger comprises a charger power supply, and wherein the charger is configured to emit radio frequency electromagnetic radiation whose frequency is optimized for energy transfer to the radio frequency energy harvesting system of the aerosol generating device.

14. The charger according to the preceding claim, wherein the charger is a mobile charger, and wherein the charger further comprises a charger radio frequency energy harvesting system configured to recharge the charger power supply.

15. A system comprising an aerosol generating device according to any one of claims 1 to 12 and a charger according to claim 13 or 14, wherein the secondary electrical device comprises means for sending out position information of the aerosol generating device, wherein the charger is configured to emit a radio frequency search signal, wherein the means for sending out position information is configured to emit a backscattered radio frequency signal upon detection of the radio frequency search signal, and wherein the charger is configured to perform one or both of the following operations upon detection of the backscattered radio frequency signal: identify the aerosol generating device and locate the aerosol generating device.

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