Claims:I/We Claim:
1. A device for simulating an avian target for detection by a radar, the device comprising:
- a meteorological balloon;
- an inflatable object;
- a set of foils configured to cover the inflatable object;
- a non-conducting mesh configured to enclose the inflatable object, and
- a nylon string, wherein one end of the nylon string is clamped to the meteorological balloon and another end of the nylon string is clamped to the non-conducting mesh.

2. The device as claimed in claim 1, wherein the inflatable object covered by the set of foils is configurable to varying sizes corresponding to varying radar cross sections of the avian target.

3. The device as claimed in claim 1, wherein the foil comprises a conductive material.

4. The device as claimed in claim 3, wherein the conductive material comprises a metallic material or non-metallic material.

5. The device as claimed in claim 1, wherein an amount of a gas used for inflating the meteorological balloon determines an altitude attainable by the device.

6. The device as claimed in claim 5, wherein the gas used for inflating the meteorological balloon is hydrogen or helium or any gas lighter than air.

7. The device as claimed in claim 1, wherein the meteorological balloon, the rope and the mesh comprise materials that are transparent to radio frequency.

8. The device as claimed in claim 1, wherein a sensor is attached with the inflatable object to monitor the direction and speed of the device.

9. The device as clamed in claim 8, wherein the sensor comprises a transmitter and a receiver.

10. The device as claimed in claim 8, wherein the sensor is remotely controllable.

, Description:DISCLAIMER
Portions of this patent document may contain material that may be subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. All copyrights and trademarks are owned by AXISCADES Aerospace & Technologies Private Limited and/or its subsidiaries/residual companies.

FIELD OF TECHNOLOGY
This disclosure relates to radar detection.

BACKGROUND
Detection theory or signal detection theory may be a means to quantify ability to discern between information-bearing patterns (referred to as stimulus in living organisms, as signal in machines) and random patterns that distract from such information-bearing patterns (also referred to as noise, consisting of background stimuli and random activity of the detection machine and of the nervous system of the operator). In the field of electronics, the separation of such patterns from a disguising background is referred to as signal recovery,
Generally, radar may be an object-detection system that uses radio waves to determine range, angle, or velocity of objects. Usually, it is used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. Typically, a radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the object(s). Radio waves (pulsed or continuous) from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed.
The modern uses of radar may be highly diverse, including air and terrestrial traffic control, radar astronomy, air-defence systems, anti-missile systems, marine radars to locate landmarks and other ships, aircraft anti-collision systems, ocean surveillance systems, outer space surveillance and rendezvous systems, meteorological precipitation monitoring, altimetry and flight control systems, guided missile target locating systems, ground-penetrating radar for geological observations, and range-controlled radar for public health surveillance. High technology radar systems are associated with digital signal processing, machine learning and may be capable of extracting useful information from very high noise levels.
A current disadvantage of the radar system may be associated with detecting birds or other flying object that can cause damage to flying objects such as aircrafts.

SUMMARY
Embodiments of the present disclosure ameliorate the disadvantages with the current radar systems. Embodiments of the present disclosure related to a device for simulating an avian target for detection by a radar, the device comprises a meteorological balloon, a non-conducting mesh configured to enclose an inflatable object, a set of foils configured to cover the inflatable object and a nylon string, wherein one end of the nylon string is clamped to the meteorological balloon and another end of the nylon string is clamped to the non-conducting mesh. Other embodiments will also be disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
For better understanding of the nature and desired objects of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference character denote corresponding parts throughout the several views. Objects, features, and advantages of embodiments disclosed herein may be better understood by referring to the following description in conjunction with the accompanying drawings. The drawings are not meant to limit the scope of the claims included herewith. For clarity, not every element may be labeled in every Figure. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments, principles, and concepts. Thus, features and advantages of the present disclosure will become more apparent from the following detailed description of exemplary embodiments thereof taken in conjunction with the accompanying drawings in which:
Figure 1 illustrates an exemplary overall setup of the simulation avian target according to an embodiment of the present disclosure; and
Figure 2 illustrates an exemplary setup of the radar reflective inflatable object (ball/balloon) in accordance with an embodiment of the present disclosure;
DETAILED DESCRIPTION
Hereinafter, various exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings, where all of these drawings and description are only presented as exemplary embodiments. It is to noted that based on the subsequent description, alternative embodiments may be conceived that may have a structure and method disclosed as herein, and such alternative embodiments may be used without departing from the principle of the disclosure as claimed in the present disclosure.
It may be appreciated that these exemplary embodiments are provided only for enabling those skilled in the art to better understand and then further implement the present disclosure, not intended to limit the scope of the present disclosure in any manner. Besides, in the drawings, for a purpose of illustration, optional steps, modules, and units may be illustrated in dotted-line blocks.
Embodiments of the present disclosure related to a device for simulating an avian target for detection by a radar. In one embodiment, the device may include an object (for example a meteorological balloon), a non-conducting mesh enclosing an inflatable object (ball/balloon), a set of foils covering the inflatable object and a nylon string, wherein one end of the nylon string is clamped to the object (meteorological balloon) and another end of the nylon string is clamped to the non-conducting mesh.
In a further embodiment, the inflatable object may be covered by the set of foils, wherein the inflatable object may be configurable to varying sizes corresponding to varying radar cross sections of an avian target. In a further embodiment, target objects of different sizes for detection by the radar may be simulate by using varying sizes of inflatable objects and/or by controlling the size of the inflatable object by an amount of gas filled in the inflatable object. In a further embodiment, an altitude attainable by the device may be determined by the amount of a gas used for inflating the object (meteorological balloon) and the inflatable object. In a further embodiment, the gas used may include at least one of hydrogen or helium or any other light weight gas that may make the inflatable object light and float in air.
In a further embodiment, the foil may include a conductive material. In a further embodiment, the conductive material may be either metallic or non-metallic material. In a further embodiment, a sensor may be attached with the inflatable object to monitor the direction and speed of the device. In a further embodiment, the weight of the sensor may be in the range varying from 1 gram to about 80 grams, and preferably less than 65 grams. In a further embodiment, the sensor may include a transmitter and a receiver. In a further embodiment, the sensor may be remotely controllable.
In one embodiment, bird detection radars may be used to study bird behavior and associated patterns to prevent bird airstrike hazard (BASH), and also to prevent birds being hit by wind mill propellers. In a further embodiment, bird behavior and associated patterns studies may help in determining immigration/migration patterns and routes as well as their habitat studies and flying behavior.
In one embodiment, flying objects such as birds may be generally non-cooperative to radar systems and therefore there may be a difficulty in calibration of radars and to accurately measure the capabilities of the radar. In a further embodiment, there may also be no way to repeat any test carried out as there may no birds behaving in similar way repeatedly. In a further embodiment, therefore, there may be a need to simulate avian targets of various radar cross sections (RCS), whose path may be predicted and repeated. In a further embodiment, though, RCS may be easily made by using objects (for example balls) of conducting surfaces, making these fly in a pattern similar to that of flying birds may be a challenge.
In one embodiment a method has been evolved by using light weight objects, preferably balls, of a required diameter. In a further embodiment, these objects may include a wrapping of a conducting material, for example aluminum foil and then hoisting these into the air by weather balloons. In a further embodiment, the size of the objects may be varied by using inflatable balls. In a further embodiment, this may allow flexibility in simulating birds of different sizes. In a further embodiment, the heights to which these simulated targets (objects) need to be hoisted may be controlled by inflating the weather balloons to different diameters. In a further embodiment, lateral travel of the simulated targets may be simulated by releasing the simulated targets at desired wind speeds and directions. In a further embodiment, this method of simulating avian targets may be used as a standard for evaluating bird detection radars all over the world.
Embodiments of the present disclosure relate to a means of simulating avian targets for testing and evaluation of Bird Detection Radar System (BDRS). In a further embodiment, the disclosure provides advantages over presently used evaluation of Bird Detection Radar System, which is typically carried out either by using remotely piloted aerial vehicles or by using trained birds as targets.
In one advantageous embodiment, the present disclosure may provide a means of simulating avian targets for testing and evaluation of bird detection radar systems, which gives full control over the size and the dynamics of the bird to be simulated. In a further advantageous embodiment, the present disclosure allows for simulating small targets for short range general purpose radars with different RCS (Radar Cross Section).
In one embodiment, the present disclosure may provide a means of simulating avian targets for testing and evaluation of Bird Detection Radar System. In a further embodiment, Bird Detection Radar may be used to detect birds of different sizes around the airfield and may be configured to warn pilots about possible hazard of a bird hit. In a further embodiment, this may also be used to warn wind farms to stop operating during times of bird migration. In a further embodiment, Bird Detection Radar System may need to be evaluated for its claimed performance by subjecting it to an environment with aerial targets. In a further embodiment, these targets may need to be of the Radar Cross Section (RCS) specified in the capability of the Radar System.
In a further embodiment, evaluation may be performed in one of the two following ways: -
(a) In one embodiment, a remotely piloted aerial vehicles (RPV) may be used to simulate avian targets. In this embodiment, due to sharp edges of the RPV the avian targets can’t be realistically simulated. In a further embodiment, the RCS can’t be varied as desired according to the evaluation criteria as the RCS of the target may depend on the radar reflective characteristics of the RPV. In a further embodiment, small birds cannot be simulated.
(b) In an alternate embodiment, trained birds may be used to fly at a desired distance from the Radar for evaluation purposes. This embodiment may be cost effective only if a large number of radars are to be evaluated and may be unsuitable for a one-off requirement.
Reference is now made to Figure 1, which illustrates an exemplary object that represents the overall setup of a simulated avian target in accordance with an embodiment of the present disclosure. The simulated avian target includes inflatable meteorological balloon (10). A non-conducting light weight rope/string is clamped to one end of meteorological balloon (10) by means of clamp (12). The other end of the rope/string is coupled to non-conducting mesh (14). Inside the mesh is placed radar reflective ball (18). Radar reflective ball is an inflatable ball, filled with a light weight gas such as hydrogen or helium or any other light weight gas having a density lesser than that of air and wrapped in a thin aluminum foil.
In one embodiment, clamp (12) may include a non-conducting material. In a further embodiment, clamp (12) may be a light weight string made of nylon or jute or cotton or any non-conducting material. In one embodiment, non-conducting mesh (14) may be an extension of the same material of the rope/string, woven in the form of a mesh. In a further embodiment, the rope/string may be approximately 1 metre in length. In a further embodiment, non-conducting mesh (14) may be a different material from that of the rope/string/ In an example embodiment, the rope string can be made of nylon and the mesh can be made to cotton. In one embodiment, radar reflective balls (18) may be filled with a desired amount of gas to mimic a particular avian target. In an example embodiment, to mimic a crow the amount of gas filled may be 3 psi, whereas to mimic an eagle the amount of gas filled may be 5 psi.
Reference is now made to Figure 2, which illustrates an exemplary radar reflective ball in accordance with the embodiments of the present disclosure. Radar reflective ball (22) simulates the avian target such as a bird. Radar reflective ball (22) is covered with a conducting metal foil (24), which is used in the radar detection. Radar reflective ball includes nozzle (20) used to fill the ball with air.
In one embodiment, conducting material (24) may include aluminum and/or copper foils. In a further embodiment, any conducting material may be used. In a further embodiment, the radar reflective ball may be completely covered with the conducting material or the conducting material may be in a particular pattern over the ball such that the conducting material is configured to reflect the radar. In an example embodiment, the radar reflective ball may be made of plastic or rubber and the ball may be covered with an aluminum foil to simulate the avian target. In a further embodiment, an altitude attainable by the system may be determined by an amount of a gas used for inflating the meteorological balloon.
In a further embodiment, the present disclosure overcomes one or more drawbacks of both the methodologies adopted for BDR System evaluation. In a further embodiment, the simulated avian target consists of a meteorological balloon of standard size (approximately 1m in diameter). In a further embodiment, the balloon may be filled with helium (He) or hydrogen (H) gas to provide buoyancy. In a further embodiment, the balloon may be clamped to a short nylon rope. In a further embodiment, a non-conducting mesh is hung from this rope. In a further embodiment, the balloon, rope and mesh may be so chosen so as to be transparent to radio frequencies and do not reflect alter the RCS measurements. A radar reflecting ball is carried in the mesh which acts as the simulated avian target for the radar. In a further embodiment, only the radar reflecting balls contribute to the RCS.
In a further embodiment, the radar reflecting object consists of an inflatable ball of required size which is covered with conducting tape made of copper or aluminum or any other conducting material. In a further embodiment, the size of the ball depends on the RCS of the avian target to be simulated. In a further embodiment, the RCS of the radar reflecting ball may be found by subjecting it to RCS measurement in an anechoic chamber.
In a further embodiment, the rate of climb of the balloon along with the under slung simulated avian target may depend on the volume of helium/hydrogen in the meteorological balloon. In a further embodiment, the dynamics of the simulated target like the dwell time within the coverage area of the radar, the horizontal drift as the balloon rises etc., may depend on the ambient wind conditions as well as the volume of the balloon at ground level. In a further embodiment, different amount of helium/hydrogen may be filled in the balloon to achieve desired target dynamics. In a further embodiment, an increase in the volume of helium/hydrogen may lead to faster ascent of the target and hence lesser drift due to wind. In a further embodiment, however, this may also result in decrease in the dwell time of the target within the radar coverage volume.
In an alternate embodiment, instead of radar reflecting ball, a payload of corner reflector may be carried. In a further embodiment, this may be utilized for evaluation of general purpose short range radars. In a further embodiment, an increase in the amount of helium/hydrogen may be used to achieve a desired rate of climb of the target depends on the weight of the payload being carried.
Any flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and /or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
Additionally, if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., “a” and/or “an” should be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations.
In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” or “one or more of A, B, and C, etc.” or “one or more of the following of A, B, and C, etc.” is used, in general such a construction is intended to include A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together, etc.
Further, any disjunctive word or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” should be understood to include the possibilities of “A” or “B” or “A and B.”
In addition, the use of “adapted to” or “configured to” in this disclosure is meant as open and inclusive language that does not foreclose devices adapted to or configured to perform additional tasks or steps.Additionally, the use of “based on” is meant to be open and inclusive, in that a process, step, calculation, or other action “based on” one or more recited conditions or values may, in practice, be based on additional conditions or values beyond those recited. Headings, lists, and numbering included herein are for ease of explanation only and are not meant to be limiting.
All examples and conditional language recited in the present disclosure are intended for pedagogical objects to aid the reader in understanding the present disclosure and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Although embodiments of the present disclosure have been described in detail, various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the present disclosure
Elements of different embodiments described herein may be combined to form other embodiments not specifically set forth above. Various elements, which are described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. Other embodiments not specifically described herein are also within the scope of the following claims.
Although the foregoing disclosure has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. The scope of the disclosure is limited only by the claims and the disclosure encompasses numerous alternatives, modifications, and equivalents. Numerous specific details are set forth in the above description in order to provide a thorough understanding of the invention. These details are provided for the purpose of example and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the invention is not unnecessarily obscured. Accordingly, the above implementations are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.