Patent ID: 12199348

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, example embodiments will be described in detail with reference to the accompanying drawings. However, various alterations and modifications may be made to the example embodiments. Here, the example embodiments are not construed as limited to the disclosure. The example embodiments should be understood to include all changes, equivalents, and replacements within the idea and the technical scope of the disclosure.

The terminology used herein is for the purpose of describing particular example embodiments only and is not to be limiting of the example embodiments. The singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises/comprising” and/or “includes/including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, such as those defined in commonly-used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

When describing the example embodiments with reference to the accompanying drawings, like reference numerals refer to like constituent elements and a repeated description related thereto will be omitted. In the description of example embodiments, detailed description of well-known related structures or functions will be omitted when it is deemed that such description will cause ambiguous interpretation of the present disclosure.

Also, in the description of the components, terms such as first, second, A, B, (a), (b) or the like may be used herein when describing components of the present disclosure. These terms are used only for the purpose of discriminating one constituent element from another constituent element, and the nature, the sequences, or the orders of the constituent elements are not limited by the terms. When one constituent element is described as being “connected”, “coupled”, or “attached” to another constituent element, it should be understood that one constituent element can be connected or attached directly to another constituent element, and an intervening constituent element can also be “connected”, “coupled”, or “attached” to the constituent elements.

The constituent element, which has the same common function as the constituent element included in any one embodiment, will be described by using the same name in other example embodiments. Unless disclosed to the contrary, the configuration disclosed in any one example embodiment may be applied to other example embodiments, and the specific description of the repeated configuration will be omitted.

FIG.1is a block diagram for a communication system according to an example embodiment, andFIG.2is a perspective view for the communication device according to an example embodiment.

Referring toFIGS.1and2, a communication system1may be configured to perform radio-wave communication with a moving object ST on a field of view. The communication system1may include a communication device10and a controller20.

The communication device10may be configured to transmit and receive radio waves to and from the moving object ST on the field of view. The communication device10may include a tracker110and a pedestal120.

The tracker110may be configured to track the moving object ST on the field of view. The tracker110may include a reflector having a reflective surface, the reflector with an approximately parabolic cross-section. The tracker110may be configured to rotate with respect to an elevational axis EL, an azimuth axis AZ, and/or a cross-level axis CL. The elevational axis EL, the azimuth axis AZ, and the cross-level axis CL may be orthogonal to each other.

The pedestal120may be configured to support the tracker110. The pedestal120may include a shaft121, a first gimbal122, and a second gimbal123.

The shaft121may be configured to rotate with respect to the azimuth axis AZ. The shaft121may have an elongated cylindrical shape. The shaft121may be installed on a reference plane of a fixed world FW.

The first gimbal122may be configured to rotate with respect to the azimuth axis AZ. The first gimbal122may be connected to the shaft121. The first gimbal122may be supported by the shaft121. For example, the first122may include a pair of first arms extending from sides of the shaft121at an upper end of the shaft121and then extending along the azimuth axis AZ.

The second gimbal123may be configured to support the tracker110and rotate with respect to the elevational axis EL. The second gimbal123may be connected to the first gimbal122. The second gimbal123may be supported by the first gimbal122. For example, the second gimbal123may include a body portion connected to the tracker110and configured to rotate with respect to the cross-level axis CL and a pair of second arms surrounding the body portion and rotatably connected to the pair of first arms of the first gimbal122.

The communication device10may be installed on the fixed world FW. For example, the fixed world FW may include a surface of the earth, a ship and the like. As a preferred example, the communication device10is installed in a ship. Since a ship performs 6-degree of freedom motions on water surface, the communication device10installed on the ship needs to track the moving object ST on the field of view while further considering motions to or with respect to multi-axial directions. Although not shown, the controller20may also be installed on the fixed world FW together with the communication device10.

The controller20may be configured to control tilting and rotating of the communication device10with respect to the elevational axis EL, the azimuth axis AZ, and/or the cross-level axis CL. The controller20may control the tilting and rotating of the communication device10according to a position of the moving object ST on the field of view. For example, the controller20may control the tilting and rotating of the communication device10considering a trajectory angle of the moving object ST on the field of view. A specific control scheme of the controller20for the communication device10will be described in detail with reference toFIGS.3through7.

FIGS.3and4are diagrams illustrating an operation of a communication device in a range of a first trajectory angle according to an example embodiment.

Referring toFIGS.3and4together, the controller20may control an operation of the communication device10for the tracker110to rotate with respect to the azimuth axis AZ and the elevational axis EL, respectively, to track the moving object ST, while the moving object ST is in a range of a first trajectory angle (±X° to)±Y° on a field of view. For example, the controller20may control rotation of the shaft121, the first gimbal122, and/or the second gimbal123for the first gimbal122to rotate with respect to the azimuth axis AZ for the second gimbal123to rotate with respect to the elevational axis EL.

In a non-limiting example, when the communication device10(SeeFIG.2) is installed on the ground, the range of the first trajectory angle may be ±10° to ±54°. In a non-limiting example, when the communication device10is installed on a ship, the range may be ±35° to ±79°.

Meanwhile, there may be a case that rotation of the tracker110with respect to the cross-level axis CL in the range of the first trajectory angle is not necessary. In this case, the controller20may prevent the tracker110from rotating with respect to the cross-level axis CL. For example, the controller20may prevent the body portion of the second gimbal123from rotating with respect to the cross-level axis CL.

FIGS.5and6are diagrams illustrating an operation of a communication device in a range of a second trajectory angle according to an example embodiment.

Referring toFIGS.5and6together, the controller20may control an operation of the communication device10to make the tracker110rotate with respect to the elevational axis EL and the cross-level axis CL, respectively, to track the moving object ST, while the moving object ST is in a range of a second trajectory angle (−X° to +X°) on a field of view. For example, the controller20may control rotation of the second gimbal123to make the second gimbal123rotate with respect to the elevational axis EL and make the body portion of the second gimbal123rotate with respect to the cross-level axis CL.

In a non-limiting example, when the communication device10(SeeFIG.2) is installed on the ground, the range of the second trajectory angle may be −10° to +10°. In a non-limiting example, when the communication device10is installed on a ship, the range may be −35° to +35°.

The controller20may tilt the tracker110with respect to the cross-level axis CL such that a rotation angle of the tracker110for the cross-level axis CL and a trajectory angle of the moving object ST may be substantially equal in the range of the second trajectory angle. The controller20may control the communication device10to maintain a tilting angle of the tracker110and the trajectory angle of the moving object ST to be substantially equal in the range of the second trajectory angle.

Meanwhile, there may be a case that the rotation of the tracker110with respect to the azimuth axis AZ in the range of the second trajectory angle is not necessary. In this case, the controller20may prevent the tracker110from rotating with respect to the azimuth axis AZ. For example, the controller20may prevent the first gimbal122from rotating with respect to the azimuth axis AZ.

FIG.7is a conceptual diagram to describe a control scheme for a communication device according to an example embodiment.

Referring toFIG.7together, a conceptual diagram is illustrated to help intuitively understand a specific control scheme of the controller20for the tracker110with respect to the elevational axis EL, the azimuth axis AZ, and/or the cross-level axis CL.

According to a conventional control scheme, the tracker110does not rotate and tilt with respect to the cross-level axis CL but follows a first movement path P1in which the tracker110rotates with respect to the elevational axis EL throughout a range of a first trajectory angle R1and a range of a second trajectory angle R2. The tracker110on the first movement path P1is bound to pass through a singular area PA on a field of view where a keyhole effect occurs. Since the tracker110requires a rapid rotation with respect to the azimuth axis AZ to smoothly track the moving object ST while the tracker110is passing through the singular area PA, a relatively large driving torque may be required for the rotation of the tracker110.

According to the control scheme of the controller20of the example embodiment, the tracker110follows a second movement path P2for avoiding the singular area PA throughout the range of the first trajectory angle R1and the range of the second trajectory range R2. For example, in the range of the first trajectory R1, the tracker110may avoid the singular area PA by rotating with respect to the elevational axis EL as in the first movement path P1and then tilting by a trajectory angle of the moving object ST with respect to the cross-level axis CL and/or maintaining the status of tilting before entering the range of the second trajectory angle R2having the singular area PA. When the tracker110enters the range of the first trajectory angle R1and starts being away from the singular area PA, the controller20may adjust a rotation angle of the tracker110for the cross-level axis CL to move along a path similar to the first movement path P1.

FIGS.8and9are graphs to describe another control scheme for a communication device according to an example embodiment.

Referring toFIGS.8and9, according to an example embodiment of a communication device, the communication device may be controlled in an alternative way different from the way described above. For example, a controller may limit an angular velocity of an azimuth angle of a tracker to below a threshold angular velocity, and in case that an angular velocity equal to or higher than the threshold angular velocity is required, the controller may control the tracker with a driving based on a three-axis (an azimuth axis, an elevational axis, and a cross-level axis) trajectory to reduce occurrence of load required for driving the tracker. Alternatively, the controller may control the tracker by using a two-axis (the azimuth axis and the elevational axis) trajectory in an environment in which the tracker is driven at the threshold angular velocity or below.

FIG.8is a graph showing changes in azimuth angles over time when maximum values of an elevation angle of the tracker are 90°, 88°, 85°, and 80°, andFIG.9is a graph showing the angular velocities of the azimuth angles of the tracker when maximum values of the elevation angle of the tracker are 90°, 88°, 85°, and 80°. In the example ofFIG.8, the threshold angular velocity may be 5 degrees per second (deg/sec). In this case, when the maximum values of the azimuth angle are 90° and 88°, a period in which the angular velocity exceeds the threshold angular velocity may be recognized.

The methods according to the above-described examples may be recorded in non-transitory computer-readable media including program instructions to implement various operations of the above-described examples. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The program instructions recorded on the media may be those specially designed and constructed for the purposes of example embodiments, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of non-transitory computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROM discs or DVDs; magneto-optical media such as optical discs; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher-level code that may be executed by the computer using an interpreter. The above-described devices may be configured to act as one or more software modules in order to perform the operations of the above-described example embodiments, or vice versa.

The software may include a computer program, a piece of code, an instruction, or some combination thereof, to independently or uniformly instruct or configure the processing device to operate as desired. Software and data may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or in a propagated signal wave capable of providing instructions or data to or being interpreted by the processing device. The software also may be distributed over network-coupled computer systems so that the software is stored and executed in a distributed fashion. The software and data may be stored by one or more non-transitory computer-readable recording mediums.

A number of example embodiments have been described above. Nevertheless, it should be understood that various modifications may be made to these example embodiments. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents.

Therefore, the scope of the disclosure is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.