Drone Network and Operation Methods

Abstract

The present disclosure relates to a drone network and operating method, wherein the drone network includes a first drone and a second drone, the first drone including a first receiver, a first transmitter, and a first processor, the second drone being positionable at a distance from the first drone. The second drone includes a second receiver, a second transmitter, and a second processor. The first transmitter is configured to transmit a signal to the second drone for reception at the second receiver, and the second processor is configured to determine a minimum signal power for the signal to be processed at the second drone. The second transmitter is configured to transmit a return signal to the first drone for reception at the first receiver. The return signal includes minimum signal power data determined by the second processor, and the first processor is configured to modulate the power of the signal transmitted from the first transmitter to the second drone based on the minimum signal power data.

Description

Technical Field

[0001] The field relates generally to unmanned aerial vehicles and, more particularly, to systems and methods for efficiently managing energy usage in a network of drones. Background Art

[0002] Unmanned aerial vehicles, such as drones, have been used to perform communications, delivery, and / or reconnaissance and surveillance missions. To perform these missions, aerial vehicles can be grouped into interconnected and at least semi-autonomous "swarms." The swarm can include multiple vehicles that communicate with each other to coordinate the operation and movement of the drones when performing a mission. Each vehicle can be equipped with communications equipment, and one or more vehicles in the swarm can be equipped with a payload for performing certain missions. In addition, aerial vehicles typically use propeller-based propulsion systems to maintain flight and travel to and / or from a target location. At least some known aerial vehicles facilitate communications, mission execution, and propulsion operations by drawing power from onboard batteries. Among other problems with known networks, batteries have a limited power supply, which limits the ability of a swarm to perform missions for extended periods of time.

[0003] This section is intended to introduce the reader to various aspects of the technology that may be related to various aspects of the present disclosure described and / or claimed below. It is believed that this discussion will help provide the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Therefore, it should be understood that these statements are to be read in this light, and not as admissions of prior art. Summary of the Invention

[0004] One aspect is a drone network. The network includes a first drone and a second drone. The first drone includes a first receiver, a first transmitter, and a first processor. The second drone is positionable at a distance from the first drone. The second drone includes a second receiver, a second transmitter, and a second processor. The first transmitter is configured to transmit a signal to the second drone for reception at the second receiver, and the second processor is configured to determine a minimum signal power for the signal to be processed by the second drone. The second transmitter is configured to transmit a return signal to the first drone for reception at the first receiver. The return signal includes minimum signal power data determined by the second processor, and the first processor is configured to modulate the power of the signal transmitted from the first transmitter to the second drone based on the minimum signal power data.

[0005] Another aspect is a drone. The drone includes a receiver subsystem configured to receive a signal, and a processor configured to determine a minimum signal power for the signal to be processed at the drone. The processor is further configured to determine excess signal power contained in the signal based on a difference between the power of the signal and the minimum signal power. The drone also includes an energy harvesting subsystem configured to harvest and store the excess signal power.

[0006] Yet another aspect is a method of controlling the operation of a drone network. The method includes transmitting a first signal from a first drone; receiving the signal at a second drone in the network; determining, at the second drone, a minimum signal power for the signal to be processed at the second drone; transmitting a return signal from the second drone to the first drone, the return signal including the minimum signal power data as determined at the second drone; and transmitting a second signal from the first drone to the second drone, wherein the power of the second signal is modulated based on the minimum signal power data.

[0007] There are various refinements of the features mentioned with respect to the above-mentioned aspects of the present disclosure. Other features may also be incorporated into the above-mentioned aspects of the present disclosure. These refinements and additional features may exist individually or in any combination. For example, the various features discussed below with respect to any of the exemplary embodiments of the present disclosure may be incorporated into any of the above-mentioned aspects of the present disclosure individually or in any combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a diagram of an example drone network.

[0009] Figure 2 It is an example management Figure 1 A flow chart of an example method for energy usage in a network is shown.

[0010] Figure 3 It is an example management Figure 1 A flow chart of an alternative method of energy usage in the network is shown.

[0011] Figure 4 Yes, you can Figure 1 A schematic diagram of the internal components of the drone used in the network is shown.

[0012] Figure 5 is a flow chart illustrating an example method of operating a drone network.

[0013] Corresponding reference numerals indicate corresponding parts throughout the drawings. DETAILED DESCRIPTION

[0014] The examples described below include systems and methods for efficiently managing energy usage in drones or drone networks. As used herein, the term "drone" refers to autonomous or remotely piloted unmanned aerial vehicles. Drones in a network can be relatively small, bee-sized, or handheld drones with a power consumption of approximately 10 watts. As a "swarm" either remains stationary at a target location or travels to or from a target location, the drones are typically spaced apart from each other. For example, a first drone at the outer edge of a swarm may be positioned at a first distance from a second drone at the opposite outer edge of the swarm, and may be positioned at a second, smaller distance from a third drone located within the swarm. In one example, for example, drones in a network use a laser communication system to facilitate high-data-rate communication between drones to coordinate drone movements and missions. As described herein, the drones' operations can be dynamically adjustable to conserve power when performing communication operations and to store excess power derived from signals sent between drones in the network or received from ground-based systems.

[0015] For example, the described systems and methods facilitate energy-efficient signal transmission between drones in a network (such as a first drone to a second, third, and / or subsequent drones). In one example, a first drone has a transmitter subsystem that transmits a signal to at least a second drone. The first drone also has a receiver subsystem that receives a return signal from the second drone. This return signal contains data that enables the first drone to modulate its signal transmission power to a minimum signal power just sufficient for processing by the second drone. Thus, the first drone conserves energy and battery life by transmitting signals at a signal power no greater than the minimum required to communicate with the second drone. However, a third drone is positioned at a second, smaller distance from the first drone, such that the modulated signal is received at the third drone with excess signal power. Therefore, the third drone includes an energy harvesting subsystem that collects the excess signal power and stores it in the third drone. The drones can be repositioned relative to each other to facilitate balancing power consumption loads and energy harvesting potential across the swarm. Thus, the drones work together to enhance the operational capabilities of the swarm and improve data transmission security by maintaining a broadcast area within the physical space defined by the swarm.

[0016] As used herein, an element or step recited in the singular and followed by the quantifier "a" or "an" should be understood as not excluding plural elements or steps, unless such exclusion is explicitly stated. Furthermore, reference to "an example," "an example implementation," or "an implementation" of the present disclosure is not intended to be interpreted as excluding the existence of additional implementations that also incorporate the referenced features.

[0017] Figure 1is a diagram of an example drone network 100. In an example implementation, network 100 includes a plurality of drones 102 defining a swarm 104. The drones 102 can move independently of one another within or outside of swarm 104 and / or can move synchronously with one another in coordinated movements. Drones 102 are wirelessly coupled to one another to facilitate and coordinate the movements of individual drones 102 within swarm 104. Furthermore, at least some drones 102 can be spaced apart by varying distances from one another within swarm 104. For example, drones 102 can include a first drone 106, a second drone 108 spaced a first distance D1 from first drone 106, and a third drone 110 spaced a smaller second distance D2 from both first drone 106 and second drone 108.

[0018] A first drone 106 and a second drone 108 may be positioned at opposite outer edges of the swarm 104, such that the second drone 108 is the drone 102 positioned farthest from the first drone 106 in the swarm 104. For effective communication between the first drone 106 and the second drone 108, signals transmitted therebetween must have a signal power greater than a threshold power level. Drones 102 positioned closer to the first drone 106 than to the second drone 108 may also be intentional or unintentional recipients of signals transmitted from the first drone 106 to the second drone 108. However, due to the proximity of other drones 102 to the first drone 106, signals transmitted from the first drone 106 to the second drone 108 may contain excess signal power when received by other drones 102, such as the third drone 110. As will be described in more detail below, the excess power contained in the signals may be collected and stored by the other drones 102 to improve the operational service time of the swarm 104.

[0019] Figure 2 is an example management network 100 ( Figure 1 1 . In an example implementation, a first drone 106 transmits a first signal 112 therefrom for reception at a second drone 108. The second drone 108 analyzes the first signal 112 to determine a minimum signal power (i.e., a threshold power level) for processing the signal transmitted from the first drone 106 at the second drone 108. For digital signals, the ability of the second drone 108 to process the signal and thus determine the minimum signal power and potential excess power in the signal is based at least in part on the ability of the second drone 108 to decrypt the bits of the bit stream defining the signal. For example, the processor ( Figure 4) can analyze the signal to determine a bit error rate, and the bit error rate can be compared to a threshold (i.e., a minimum signal error rate). If the determined bit error rate exceeds the threshold, the minimum signal power is verified and excess signal power may be present. For analog signals, the ability of the second drone 108 to process the signal is based at least in part on the spurious-free dynamic range (SFDR) of the signal. For example, the minimum signal power can be determined to be at the lower end of the SFDR, and excess signal power can be determined to be present at any power level greater than the lower end of the SFDR.

[0020] In one example, the first drone 106 transmits the first signal 112 with an attenuated power level to facilitate determining the minimum signal power. Figure 2 In the illustrated first process step 114, first drone 106 transmits first signal 112 at a first signal power greater than the minimum power required for processing of first signal 112 at second drone 108. If first drone 106 continues to transmit first signal 112 at the first signal power, valuable power reserves within first drone 106 may be depleted at an inefficient rate. Furthermore, transmitting first signal 112 at a signal power greater than that required for processing at second drone 108 may cause first signal 112 to be outside network 100, thereby being received by unsecured and unintended third-party recipients. Therefore, from first process step 114 to second process step 116, the signal power of first signal 112 is gradually reduced from the first signal power to a second signal power. In an exemplary implementation, the decaying power level of first signal 112 is monitored at second drone 108, and second drone 108 analyzes the decaying power level to determine the minimum signal power for first signal 112 to be processed at second drone 108.

[0021] In a third process step 118, second drone 108 transmits a return signal 120 to first drone 106. Return signal 120 includes minimum signal power data, which provides first drone 106 with information about the power level used to transmit first signal 112 to second drone 108, enabling first signal 112 to be processed at second drone 108. Return signal 120 may be transmitted to first drone 106 at the minimum signal power. First drone 106 receives return signal 120 and modulates the power of the signal to be transmitted to second drone 108 based on the minimum signal power data. Thus, in a fourth process step 122, efficient and power-efficient communication is established between first drone 106 and second drone 108. Specifically, first signal 112 and return signal 120 are transmitted between first drone 106 and second drone 108 at the minimum signal power, thereby helping to conserve energy for both first drone 106 and second drone 108.

[0022] In the example implementation, throughout process steps 114, 116, 118, and 122, the third drone 110 is located between the first drone 106 and the second drone 108. In operation, the third drone 110 analyzes the first signal 112 and the return signal 120 to determine a minimum signal power for the signals transmitted from the first drone 106 and the second drone 108 to be processed at the third drone 110. Because the third drone 110 is located at a smaller second distance D2 (between the first and second drones 106 and 108) from the first and second drones 106 and 108, the third drone 110 is located between the first and second drones 106 and 108. Figure 1 ), the minimum signal power for processing the first signal 112 and the return signal 120 at the third drone 110 is less than, for example, the minimum signal power for processing the first signal 112 at the second drone 108. Therefore, the third drone 110 may determine that the first signal 112 and the return signal 120 contain excess signal power when received at the third drone 110. The excess signal power may be determined based on the difference between the power of the first signal 112 and the return signal 120 received at the third drone 110 and the minimum signal power for processing the signals at the third drone 110. Therefore, the third drone 110 may collect and store the excess signal power to improve its operational capability and service life.

[0023] Figure 3 is an example management network 100 ( Figure 1 As described above, the second drone 108 analyzes the first signal 112 transmitted from the first drone 106 to determine the minimum signal power at which the signal transmitted from the first drone 106 is processed at the second drone 108. In an example implementation, the first drone 106 transmits the first signal 112 with a fixed power level to facilitate determining the minimum signal power. For example, Figure 3In the illustrated first process step 124, first drone 106 transmits first signal 112, whose signal power is greater than the minimum power required for first signal 112 to be processed at second drone 108. Second drone 108 then attenuates the power level of first signal 112 by an attenuation value. This attenuation value is determined based on the difference between the minimum signal power and the power of first signal 112 received at second drone 108. In a second process step 126, second drone 108 transmits a return signal 120 to first drone 106. Return signal 120 contains minimum signal power data, including the attenuation value determined by second drone 108. First drone 106 receives return signal 120 and modulates the power of the signal transmitted to second drone 108 based on the minimum signal power data, such as by modulating the signal power proportionally to the attenuation value. Thus, in a third process step 128, efficient and power-efficient communication is established between first drone 106 and second drone 108. Specifically, the first signal 112 and the return signal 120 are transmitted between the first drone 106 and the second drone 108 with minimum signal power to help conserve energy of the first drone 106 and the second drone 108 .

[0024] exist Figure 2 and Figure 3 In the example shown, if interference, for example, limits the ability of the second drone 108 to process the signal 112 , the power of the signal transmitted from the first drone 106 may also be increased to determine a minimum signal power.

[0025] Refer again Figure 1 , drones 102 in swarm 104 can move independently of one another within or outside of network 100, and / or can move synchronously with one another in coordinated movements. For example, swarm 104 can be positioned at a fixed location relative to the Earth while drones 102 move relative to one another. Alternatively, swarm 104 can move at a speed relative to the Earth while drones 102 move relative to one another. In either example, drones 102 can move relative to one another to facilitate balancing power consumption loads and energy harvesting potential across swarm 104.

[0026] For example, in Figure 1In the illustrated swarm configuration, first drone 106 may have a greater power consumption load than third drone 110 due to the need for first drone 106 to use more power than third drone 110 to effectively communicate with second drone 108. Thus, first drone 106 may move inward from its position at the outer edge of swarm 104, thereby decreasing the distance of first drone 106 relative to other drones 102 in swarm 104 and reducing the amount of power available for effective communication with other drones 102. In one example, first drone 106 may move to the relative center of swarm 104 after being at the outer edge for a predetermined amount of time or based on an analysis of the remaining battery life of first drone 106.

[0027] In another example, first drone 106 and third drone 110 may switch relative positions within swarm 104 such that third drone 110 moves from the relative center of swarm 104 to the outer edge of swarm 104. During operation of swarm 104 and up until the time of the position switch, third drone 110 uses less transmission power and also collects power from other drones 102. Thus, moving first drone 106 and third drone 110 relative to each other also helps balance power consumption loads and energy collection potential across swarm 104.

[0028] While the above description has been discussed in the context of drones 106 , 108 , and 110 , it should be understood that the receiving, analyzing, power modulation, and transmitting processes may be performed simultaneously by all drones 102 in the network 100 to help manage energy conservation.

[0029] Figure 4 is available for network 100( Figure 1 1 is a schematic diagram of the internal components of a drone 102 (shown in FIG). In an example implementation, drone 102 includes a transmitter subsystem 130, a receiver subsystem 132, an energy harvesting subsystem 134, and a processor 136. Subsystems 130, 132, and 134 may share one or more components with each other. Thus, drone 102 includes a collection lens 138 and a culminating lens 140 for transmitting outgoing signals 142 and for receiving incoming signals 144 from other drones 102.

[0030] When in the first receive mode, the incoming signal 144 is routed through the lenses 138 and 140 to a circulator 146. The circulator 146 can be a free-space optical circulator or a fiber-based circulator 146. The circulator 146 is a passive multi-port device that enables signals to be sent and received from the same component. Therefore, the incoming signal 144 received at the circulator 146 is routed to a tunable beam splitter 148, which is controlled by the processor 136 to determine the splitting ratio to be performed by the beam splitter 148. In an alternative example, the incoming signal 144 received at the circulator 146 is routed to a tunable fiber coupler (not shown). In one example, the processor 136 controls the beam splitter 148 to split the incoming signal 144 into a first output 150 and a second output 152. The first output 150 is routed to the processor 136, and the second output 152 is routed to components of the energy harvesting subsystem 134, as will be described in more detail below.

[0031] In an example implementation, the first output 150 is routed through an optical filter 154 and a receiver 156 positioned between the beam splitter 148 and the processor 136. The optical filter 154 filters noise from the first output 150 and the receiver 156 of the incoming signal 144. The receiver 156 may be defined by a photodiode that converts an optical signal into an electronic signal and an electrical filter that filters electrical noise from the signal. The processor 136 then analyzes the first output 150 to determine a minimum signal power for the incoming signal 144 to be processed at the drone 102. The transmitter subsystem 130 includes a laser transmitter 158 in communication with the processor 136 and a collimator 160 positioned between the laser transmitter 158 and the lenses 138 and 140. Thus, in one example, once the minimum signal power has been determined, the processor 136 controls the laser transmitter 158 to transmit an outgoing signal 142 (e.g., the return signal 120) containing the minimum signal power data, as described above. In one embodiment, the laser transmitter 158 is a CWNd 3+ :YAG launcher.

[0032] In an alternative example, a limited number of drones 102 in the swarm 104 have independent laser transmitters 158 mounted thereon, and the remaining drones 102 have laser transmitters 158 mounted thereon that act as modulated retroreflectors. Thus, the limited number of drones 102 (e.g., a single drone 102) can be the source of the laser transmission, and the remaining drones 102 can conserve energy by reflecting signals received from the source.

[0033] While in the first receive mode, processor 136 also analyzes incoming signal 144 to determine the presence of excess signal power therein. Incoming signal 144 may be received from other drones 102 in swarm 104 or from a ground-based system. If it is determined that incoming signal 144 contains excess signal power, processor 136 may adjust the ratio of beam splitter 148 to enable second output 152 of incoming signal 144 to be routed to energy harvesting subsystem 134. In an example implementation, energy harvesting subsystem 134 includes photovoltaic (PV) cells 162, a DC-DC (power) converter 164, and a battery 166 electrically connected to power-consuming components of drone 102. In operation, PV cells 162 convert energy from incoming signal 144 (i.e., laser transmission) into electricity, and DC-DC converter 164 further converts the electricity for storage within battery 166. Alternatively, the output of the DC-DC converter may be routed directly to energy-consuming components of drone 102.

[0034] While in the second receive mode, the drone 102 can be the recipient of an incoming signal 144 containing minimum signal power data. The incoming signal 144 can be analyzed by the processor 136, and the operation of the transmitter subsystem 130 can be adjusted accordingly to help conserve battery 166. In an example implementation, the transmitter subsystem 130 includes an optical modulator 168 that receives output from the laser transmitter 158 and selectively manipulates the output to produce the outgoing signal 142. For example, if the processor 136 determines that the outgoing signal 142 is transmitted at a power level greater than the minimum signal power, the optical modulator 168 can operate to reduce the power level of the outgoing signal 142 to the minimum signal power.

[0035] Figure 5 2 is a flow chart illustrating an example method 200 for operating a drone network. The method 200 includes transmitting 202 a first signal from a first drone; receiving 204 the signal at a second drone in the network; determining 206 at the second drone a minimum signal power for a signal to be processed at the second drone; transmitting 208 from the second drone to the first drone a return signal containing minimum signal power data determined at the second drone; and transmitting 210 a second signal from the first drone to the second drone, wherein the power of the second signal is adjusted based on the minimum signal power data.

[0036] Additionally, the present disclosure includes the following examples, the scope of which is provided by the claims.

[0037] Example 1. A drone network, comprising: a first drone, the first drone comprising a first receiver, a first transmitter, and a first processor; and a second drone, the second drone being positionable at a distance from the first drone, the second drone comprising a second receiver, a second transmitter, and a second processor, wherein the first transmitter is configured to transmit a signal to the second drone for receipt at the second receiver, and the second processor is configured to determine a minimum signal power of the signal to be processed at the second drone, wherein the second transmitter is configured to transmit a return signal to the first drone for receipt at the first receiver, the return signal comprising minimum signal power data determined by the second processor, and the first processor is configured to modulate the power of the signal transmitted from the first transmitter to the second drone based on the minimum signal power data.

[0038] Example 2. The network of Example 1, wherein the first transmitter is configured to transmit a signal having an attenuated power level, and wherein the second processor is configured to monitor the attenuated power level to determine the minimum signal power.

[0039] Example 3. A network according to any one of Examples 1 to 2, wherein the first transmitter is configured to transmit a signal having a fixed power level, and wherein the second processor is configured to generate the minimum signal power data based on an attenuation value, the attenuation value being determined based on a difference between the power of the signal and the minimum signal power.

[0040] Example 4. A network according to any of Examples 1 to 3, wherein the first processor is configured to modulate the power of a signal to be transmitted to the second drone to a power level approximately equal to the minimum signal power.

[0041] Example 5. A network according to any one of Examples 1 to 4, wherein the second processor is further configured to determine excess signal power contained in the signal based on a difference between the power of the signal and the minimum signal power, and the second drone also includes an energy collection subsystem configured to collect the excess signal power and store the excess signal power within the second drone.

[0042] Example 6. A network according to any one of Examples 1 to 5, further comprising a third drone that can be positioned at a smaller distance from the first drone than the second drone, wherein the third drone comprises: a third receiver configured to receive a signal transmitted by the first drone; a third processor configured to determine a minimum signal power of the signal to be processed at the third drone and determine excess signal power contained in the signal based on a difference between the power of the signal and the minimum signal power; and an energy collection subsystem configured to collect the excess signal power and store the excess signal power within the third drone.

[0043] Example 7. A network according to Example 6, wherein the third drone further comprises a third transmitter configured to transmit a return signal to the first drone for receipt at the first receiver, the return signal comprising minimum signal power data determined by the third processor, wherein the first processor is configured to modulate the power of signals transmitted from the first transmitter to the second drone and the third drone based on an analysis of the minimum signal power data contained in the return signal.

[0044] Example 8. A drone comprising: a receiver subsystem configured to receive a signal; a processor configured to determine a minimum signal power of the signal to be processed at the drone and to determine excess signal power contained in the signal based on a difference between the power of the signal and the minimum signal power; and an energy collection subsystem configured to collect and store the excess signal power.

[0045] Example 9. The drone of Example 8, further comprising a transmitter subsystem comprising a laser transmitter and an optical modulator, both of which are controllable by the processor, the laser transmitter being configured to provide an output to the optical modulator, the optical modulator being configured to selectively modulate the power of the output to form a signal to be transmitted from the drone.

[0046] Example 10. A drone according to Example 9, wherein the processor is configured to identify whether there is excess signal power in the signal, and is configured to modulate the power of the transmitted signal using the optical modulator when the excess signal power is identified.

[0047] Example 11. A drone according to any of Examples 9 to 10, wherein the laser transmitter comprises a modulated retroreflector.

[0048] Example 12. A drone according to any of Examples 9 to 11, further comprising a circulator configured to selectively route inputs and outputs between the receiver subsystem and the transmitter subsystem.

[0049] Example 13. The drone of Example 8, further comprising a transmitter subsystem configured to transmit a return signal from the drone, the return signal comprising minimum signal power data determined by the processor.

[0050] Example 14. A drone according to Example 8, wherein the receiver subsystem includes a beam splitter controllable by the processor, and wherein the energy collection subsystem includes a battery, wherein the processor is configured to identify whether there is excess signal power in the signal based on a first output received from the beam splitter, and is configured to instruct the beam splitter to provide a second output containing the excess signal power to the battery when the excess signal power is identified.

[0051] Example 15. The drone of Example 14, wherein the energy harvesting subsystem further comprises a photovoltaic cell and a power converter coupled between the beam splitter and the battery for converting the second output into storable power.

[0052] Example 16. A method for controlling the operation of a drone network, the method comprising the following steps: transmitting a first signal from a first drone; receiving the signal at a second drone in the network; determining at the second drone a minimum signal power for the signal to be processed at the second drone; transmitting a return signal from the second drone to the first drone, the return signal containing minimum signal power data determined at the second drone; and transmitting a second signal from the first drone to the second drone, wherein the power of the second signal is modulated based on the minimum signal power data.

[0053] Example 17. The method according to Example 16 further includes the following steps: receiving the signal at a third drone in the network, wherein the third drone can be positioned at a smaller distance from the first drone than the second drone; storing excess signal power contained in the signal transmitted from the first drone at the third drone; selectively moving the first drone, the second drone and the third drone relative to each other so that the second drone is positioned at a smaller distance from the third drone than the first drone; and storing excess signal power contained in the signal transmitted from the first drone at the second drone.

[0054] Example 18. A method according to Example 17, wherein the first drone, the second drone and the third drone define a drone swarm, and the method further includes the following steps: when the first drone, the second drone and the third drone move relative to each other, the drone swarm is positioned at a fixed position relative to the earth.

[0055] Example 19. A method according to any one of Examples 17 to 18, wherein the first drone, the second drone, and the third drone define a drone swarm, the method further comprising the following steps: when the first drone, the second drone, and the third drone move relative to each other, so that the drone swarm moves at a speed relative to the earth.

[0056] Example 20. A method according to any one of Examples 17 to 19, wherein a plurality of drones including at least the first drone and the second drone define a drone swarm, and the method further comprises the following steps: moving the first drone to the relative center of the drone swarm.

[0057] This written description uses examples to disclose different implementations, including the best mode, and also to enable those skilled in the art to practice the different implementations, including making and using any devices or systems and performing any combined methods. The patentable scope of the disclosure is defined by the claims and may include other examples that occur to those skilled in the art after reading this specification. Such other examples are intended to fall within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A drone network (100), comprising: a first drone (106) comprising a first receiver (132), a first transmitter (130), and a first processor (136); and A second drone (108) is configured to be positioned at a distance from the first drone (106), the second drone (108) comprising a second receiver (132), a second transmitter (130), and a second processor (136), wherein the first transmitter (130) is configured to transmit a signal (112) to the second drone (108) for receipt at the second receiver (132), and the second processor (136) is configured to determine the signal to be processed at the second drone (108). a minimum signal power of a transmitted signal (112), wherein the second transmitter (130) is configured to transmit a return signal (120) to the first drone (106) for receipt at the first receiver (132), the return signal (120) containing minimum signal power data determined by the second processor (136), and the first processor (136) is configured to modulate the power of a signal (112) to be transmitted from the first transmitter (130) to the second drone (108) based on the minimum signal power data, The second processor (136) is further configured to determine excess signal power contained in the transmitted signal based on a difference between the power of the transmitted signal (112) and the minimum signal power, and the second drone (108) further includes an energy collection subsystem (134), which is configured to collect the excess signal power and store the excess signal power in the second drone (108).

2. The drone network (100) according to claim 1, wherein: The first transmitter (130) is configured to transmit a signal (112) having an attenuated power level, and wherein the second processor (136) is configured to monitor the attenuated power level to determine the minimum signal power.

3. The drone network (100) according to claim 1 or 2, wherein: The first transmitter (130) is configured to transmit a signal (112) having a fixed power level, and wherein the second processor (136) is configured to generate the minimum signal power data based on an attenuation value, the attenuation value being determined based on a difference between a power of the transmitted signal (112) and the minimum signal power.

4. The drone network (100) according to claim 1 or 2, wherein: The first processor (136) is configured to modulate the power of a signal (112) to be transmitted to the second drone (108) to a power level approximately equal to the minimum signal power.

5. The drone network (100) of claim 1 or 2, further comprising a third drone (110) that is positionable at a smaller distance from the first drone (106) than the second drone (108), wherein: The third drone (110) comprises: a third receiver (132) configured to receive a signal (112) transmitted by the first drone (106); a third processor (136) configured to determine a minimum signal power of the transmitted signal (112) to be processed at the third drone (110), and to determine excess signal power contained in the transmitted signal (112) based on a difference between the power of the transmitted signal (112) and the minimum signal power; and An energy harvesting subsystem (134) is configured to harvest the excess signal power and store the excess signal power within the third drone (110).

6. The drone network (100) according to claim 5, wherein: The third drone (110) further includes a third transmitter (130) configured to transmit a return signal (120) to the first drone (106) for receipt at the first receiver (132), the return signal (120) including minimum signal power data determined by the third processor (136), wherein the first processor (136) is configured to modulate the power of a signal (112) transmitted from the first transmitter (130) to the second drone and the third drone (110) based on an analysis of the minimum signal power data included in the return signal (120).

7. The drone network (100) according to claim 5, wherein: The first drone (106), the second drone (108) and the third drone (110) include: a receiver subsystem (132), the receiver subsystem (132) configured to receive a signal (144); a processor (136) configured to determine a minimum signal power of the received signal (144) to be processed at the drone and to determine excess signal power contained in the received signal (144) based on a difference between the power of the received signal (144) and the minimum signal power; and An energy harvesting subsystem (134) is configured to harvest and store the excess signal power.

8. The drone network (100) according to claim 7, wherein: Each drone (106, 108, 110) also includes a transmitter subsystem (130), the transmitter subsystem (130) including a laser transmitter (158) and an optical modulator (168), both of which are controllable by the processor (136), the laser transmitter (158) being configured to provide an output to the optical modulator (168), and the optical modulator (168) being configured to selectively modulate the power of the output to form a signal (142) to be transmitted from each drone (106, 108, 110).

9. The drone network (100) according to claim 8, wherein: Define at least one of the following: The processor (136) is configured to identify whether excess signal power is present in the received signal (144) and to modulate the power of the transmitted signal (142) using the optical modulator (168) when the excess signal power is identified; The laser emitter (158) includes a modulated retroreflector; and A circulator (146) configured to selectively route inputs and outputs between the receiver subsystem (132) and the transmitter subsystem (130).

10. A method of controlling the operation of a drone network (100), the method comprising the steps of: Transmitting a first signal (112) from a first drone (106); Receiving the first signal (112) at a second drone (108) in the drone network (100); determining, at the second drone (108), a minimum signal power of the first signal (112) to be processed at the second drone (108); transmitting a return signal (120) from the second drone (108) to the first drone (106), the return signal including minimum signal power data determined at the second drone (108); transmitting a second signal (112) from the first drone (106) to the second drone (108), wherein a power of the second signal (112) is modulated based on the minimum signal power data; determining, at the second drone, an excess signal power contained in the first signal based on a difference between the power of the first signal (112) and the minimum signal power; and The excess signal power is collected at the second drone and stored in the second drone (108).

11. The method according to claim 10, further comprising the steps of: receiving the first signal (112) at a third drone (110) in the drone network (100), wherein the third drone (110) is positionable at a smaller distance from the first drone (106) than the second drone (108); storing, at the third drone (110), excess signal power contained in the first signal (112) transmitted from the first drone (106); and The first drone (106), the second drone (108), and the third drone (110) are selectively moved relative to each other to position the second drone (108) at a smaller distance from the first drone (106) than the third drone (110).

12. The method according to claim 11, wherein The first drone (106), the second drone (108), and the third drone (110) define a drone swarm (104), and the method further includes the step of positioning the drone swarm (104) at a fixed position relative to the earth when the first drone (106), the second drone (108), and the third drone (110) move relative to each other.

13. The method according to claim 11 or 12, wherein: The first drone (106), the second drone (108), and the third drone (110) define a drone swarm (104), and the method further includes the step of causing the drone swarm (104) to move at a speed relative to the earth when the first drone (106), the second drone (108), and the third drone (110) move relative to each other.

14. The method according to claim 11 or 12, wherein: A plurality of drones including at least the first drone (106) and the second drone (108) define a drone swarm (104), and the method further comprises the following steps: moving the first drone (106) to a relative center of the drone swarm (104).

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