Patent Description:
Confocal communication satellites are employed to receive electromagnetic signals from ground components, process the signals and/or retransmit the signals to other ground components. The signals contain various types of information ranging from voice, video, data, images, etc. for communication between various ground components through the satellite. The satellite can thus both receive information and transmit information.

Satellites employ antennas to transmit and receive signals, and can be fixed optical systems that do not permit modification of positions of components relative to each other once live. Antennas have the ability to direct the signals to a specific location and the ability to tune to signals emanating from a specific location. Antennas can transmit signals having given frequencies to a specific location by focusing the signals into a radiation pattern. Similarly, antennas tune to the same radiation pattern to receive signals with the given frequencies emanating from the specific location. The gain of an antenna is the measure of the ability of an antenna to increase the power to a given area by reducing the power to other areas (e.g., a sensitivity of the antenna). The gain can be related to the size of the radiation pattern and is related to a data rate that the antenna can support (e.g., the higher the gain the higher the data rate). Document: <NPL>, according to its abstract, the zooming and scanning capabilities of a Gregorian confocal dual reflector antenna are described. The basic antenna configuration consists of two oppositely facing paraboloidal reflectors sharing a common focal point. A planar feed array is used to illuminate the subreflector allowing the antenna to scan its beam. The resulting quadratic aberrations can be compensated by active mechanical deformation of the subreflector surface, which is based on translation, rotation and focal length adjustment. In order to reduce the complexity of the mechanical deformation, least squares fit paraboloids are defined to approximate the optimal correction surface. These best fit paraboloids considerably reduce scanning losses and pattern degradation. This work also introduces two different zooming techniques for the Gregorian confocal dual reflector antenna: the first consists of introducing a controlled quadratic path error to the main reflector aperture; and the second is based on reducing the size of the radiating aperture of the feeding array.

Document <CIT> discloses a mechanically adjustable confocal dual reflector antenna with a feed horn.

In a first aspect, there is provided a system according to claim <NUM>, and in a second aspect, there is provided a method according to claim <NUM>.

The various advantages of the examples will become apparent to one skilled in the art by reading the following specification and appended claims, and by referencing the following drawings, in which:.

Turning now to <FIG>, process <NUM> of adjusting a radiation pattern <NUM> of a satellite <NUM> is illustrated. The radiation pattern <NUM> corresponds to a "FOV" of the satellite <NUM>. The satellite <NUM> can target a spot beam (e.g., a focused beam that is increased and concentrated in power to increase gain) within the radiation pattern <NUM> so that the spot beam covers only a fraction of the radiation pattern <NUM> (increases gain in the fraction) and is able to be moved within the radiation pattern <NUM>. Conversely the satellite <NUM> can transmit a wide beam (e.g., a less focused beam that is decreased in power) to cover the entire radiation pattern <NUM> while reducing the gain. Thus, the radiation pattern <NUM> is a maximum coverage area of the satellite <NUM>.

The satellite <NUM> includes an antenna assembly that includes a main reflector 104a (e.g., a parabolic reflector, a semi-parabolic reflector or a shaped reflector), a sub-reflector 104b, an Integrated Phased Array (IPA) feed system 104c and a supporting body 104d. The satellite <NUM> further includes an adjustment mechanism 104e that can adjust a position of the main reflector 104a relative to both the sub-reflector 104b and IPA feed system 104c to adjust optics of the satellite <NUM> (e.g., zoom in on an area of the Earth, zoom out from the area, increase gain, decrease gain, change area of focus, adjust size, shape and/or position FOV, etc.). The adjustment mechanism 104e is attached to the supporting body 104d.

The IPA feed system 104c is directed at the sub-reflector 104b. The satellite <NUM> can operate in a transmission and reception mode. In a transmission mode, the IPA feed system 104c illuminates the sub-reflector 104b with electromagnetic energy. The electromagnetic energy can be radio-frequency (RF) signals. The sub-reflector 104b then reflects this energy to illuminate the main reflector 104a. The main reflector 104a reflects and focuses the electromagnetic energy to generate radiation pattern <NUM> on the Earth. The IPA feed system 104c can be located at a common focal point of the main reflector 104a and the sub-reflector 104b. For example, the IPA feed system 104c can be located in a collimated beam produced by the main reflector 104a and the sub-reflector 104b. Thus, the IPA feed system 104c can intercept reflected electromagnetic energy (e.g., a beam) from the main reflector 104a via the sub-reflector 104b to receive transmissions.

The satellite <NUM> includes a confocal antenna that provides magnification of the radiation pattern <NUM>. The satellite <NUM> includes the confocal antenna that provides magnification of the radiation pattern <NUM>. In the baseline configuration, the satellite <NUM> determines a relation between the main reflector 104a optics and the sub-reflector 104b optics based on the main reflector 104a baseline focal length which maintains common main reflector 104a and sub-reflector 104b focal points to set the radiation pattern <NUM>. For example, in a baseline configuration, the satellite <NUM> sets a ratio between focal lengths of the main reflector 104a and sub-reflector 104b, while maintaining a common focal point to set the radiation pattern <NUM>. Once the main reflector 104a is moved from a baseline location of the baseline configuration, the focal points of the main reflector 104a and the sub-reflector 104b are no longer common. Embodiments can adjust an "effective" focal length for the main reflector 104a to change the magnification as the main reflector 104a is moved and adjust the IPA feed system 104c to compensate for aberrations.

The radiation pattern <NUM> includes attributes such as size and gain (e.g., maximum gain) which can be adjustable by changing a distance between the main reflector 104a and the sub-reflector 104b, and adjusting operating parameters of the IPA feed system 104c. For example, in this example the distance is increased to be set to a length d<NUM> to increase the magnification. Thus, by increasing the distance, the radiation pattern <NUM> can correspondingly be reduced in size but have an increased gain. The increased gain can facilitate higher fidelity communications at a cost to a size of the radiation pattern <NUM>. For example, the increased gain can increase a throughput (e.g., increase a rate of message reception and delivery) and/or bandwidth to a covered area. For example, the increased gain can enable higher throughput or data bandwidth for an exchange of a reduced size of the radiation pattern <NUM> (e.g., a coverage area). Conversely, decreasing the distance will result in a decrease in throughput and/or data bandwidth with an increase in size of the radiation pattern <NUM> or coverage size is obtained.

Adjusting the distance to D<NUM> can result in undesirable aberrations to the shape of the radiation pattern <NUM> (e.g., beam main lobe and sidelobe integrity can be reduced). To mitigate, reduce or eliminate the aberrations, examples include controlling the IPA feed system 104c. Other confocal antennas provide magnification of the antenna radiation pattern by setting the ratio between focal lengths of a main reflector and sub-reflector, while maintaining a common focal point. Changing the focal point of each reflector requires modification of the reflector shape, while maintaining a common focal point requires repositioning of the reflectors about multiple axes. In contrast, some examples simplify the readjustment process by altering performance parameters of the IPA feed system 104c to reduce and/or eliminate aberrations and maintain beam main lobe and sidelobe integrity.

That is, examples described herein allow the confocal antenna system to provide magnification with translation being limited to a single axis and without changing the shape of the main reflector 104a. Complexity of the overall process is dramatically reduced using the IPA feed system 104c (e.g., an electronically-reconfigurable phased array feed that is capable of digital signal processing) that compensates for non-idealities introduced by fixed focal lengths, single axis translation and different focal points. Thus, the IPA feed system 104c assures beam main lobe and sidelobe integrity of the radiation pattern <NUM> at any main reflector 104a position and magnification.

For example, the IPA feed system 104c emits electromagnetic energy towards the sub-reflector 104b where the sub-reflector 104b reflects the electromagnetic energy to the main reflector 104a. The IPA feed system 104c is an electronically-reconfigurable phased array feed that adjusts the electromagnetic energy emitted from the IPA feed system 104c to reduce or eliminate one or more aberrations caused by moving the main reflector 104a. For example, a direction of the electromagnetic energy emitted from the IPA feed system 104c can be electronically adjusted for example by adjusting emitter phases, and/or amplitude and phase of the electromagnetic energy emitted from the IPA feed system 104c to steer a beam of the electromagnetic energy emitted from the IPA feed system 104c. For example, the IPA feed system 104c suppresses an amount of the electromagnetic energy emitted in a first direction from the IPA feed system 104c towards the sub-reflector 104b, and increases an amount of the electromagnetic energy emitted in a second direction from the IPA feed system 104c towards the sub-reflector 104b. Doing so can adjust where the electromagnetic energy impinges on the sub-reflector 104b. Thus, some examples can include the IPA feed system 104c electronically beam steering electromagnetic energy to the sub-reflector 104b to control where the beam strikes the sub-reflector 104b.

In addition to steering phase correction, the IPA feed system 104c can correct for higher order phase distortions caused by a reflector system including main reflector 104a and sub-reflector 104b. Such phase distortions include spherical phase errors, parabolic phase errors, and comma phase errors up to any polynomial. These corrections can be combined with the correction to steering using the process of superposition of waves of electromagnetic energy emitted from the IPA feed system 104c. In some examples, the superposition of waves means the phase of individual emitters of the array required to steer the beam in the desired direction can be linearly added to the complex excitation (e.g., amplitude and phase) of individual emitters of the array required to correct for higher order phase distortions to obtain an excitation that both steers the beam and corrects for higher order phase distortions of the array.

In this example, the radiation pattern <NUM> is at a first size and has a first gain. The process <NUM> conducts an identification that the radiation pattern <NUM> is to be adjusted so as to adjust the first size to a second size and adjust the first gain to a second gain. For example, the satellite <NUM> can receive an instruction from a ground component to adjust the radiation pattern <NUM> from a first size and a first gain to a second size and a second gain. In response to the identification, the process <NUM> adjusts the radiation pattern <NUM>, <NUM>. For example, main reflector 104a can be moved linearly along an axis <NUM> by the adjustment mechanism 104e. The axis <NUM> can be perpendicular to a reflective surface of the main reflector 104a that reflects the electromagnetic energy from the sub-reflector 104b.

Concurrently, the IPA feed system 104c electronically steers a beam of the electromagnetic energy emitted from the IPA feed system 104c towards the sub-reflector 104b. For example, main reflector 104a is moved relative to the sub-reflector 104b and the IPA feed system 104c along the axis <NUM>. The sub-reflector 104b and the IPA feed system 104c can remain stationary on the satellite <NUM>. The IPA feed system 104c can adjust for aberrations caused by moving the main reflector 104a through beam steering. Doing so can enhance a shape of the radiation pattern <NUM> by forming the radiation pattern <NUM> into a desired shape (e.g., circular) while bypassing other corrective measures, such as rotating the main reflector 104a, to enhance the shape. Thus, it can be sufficient to linearly move the main reflector 104a along axis <NUM> while adjusting the beam of the IPA feed system 104c to adjust the radiation pattern <NUM>, without rotating the main reflector 104a. In some examples, the adjustment mechanism 104e can also rotate the main reflector 104a along, or about, a second axis perpendicular to the first axis if desired, but doing so is unnecessary in some examples. Such adjustments can be pre-programmed in an a-priori situation.

In this example, the distance is decreased from length d<NUM> to length d<NUM> while the IPA feed system 104c adjusts the emission of electromagnetic energy described above. Doing so increases the size of the radiation pattern <NUM> (zooms out to increase the FOV) as illustrated in the bottom portion of <FIG>, and further lowers the gain. In some examples, the sub-reflector 104b is also moveable. For example, the sub-reflector 104b can be moved relative to the main reflector 104a and the IPA feed system 104c. For example, the sub-reflector 104b can be moved in any direction, and can be rotatable, moved linearly along an axis, etc..

<FIG> illustrates a defocused confocal antenna <NUM>. Some elements are omitted for clarity. Examples of <FIG> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>). In this example, a reflector bore sight <NUM> of the main reflector <NUM> extends upwardly. The bore sight <NUM> is the axis of maximum gain and/or peak gain. A defocusing vector <NUM> is approximately perpendicular to a major surface of the main reflector <NUM>. The defocusing vector <NUM> is separate from the reflector bore sight <NUM> by α°. IPA feed system <NUM> transmits electromagnetic energy to main reflector <NUM> via sub-reflector <NUM> along path <NUM>. Thus, the defocused confocal antenna <NUM> reflects the electromagnetic energy from the main reflector <NUM> to generate a radiation pattern on a body, such as planet Earth.

In order to adjust the radiation pattern, the main reflector <NUM> is adjusted. A movement mechanism <NUM> transitions the main reflector <NUM> linearly along the defocusing vector <NUM> (e.g., a first axis). For example, a telescoping boom 214b can linearly move the main reflector <NUM>. In some examples, the main reflector <NUM> need only be linearly adjusted without rotating the main reflector <NUM>.

A rotational "nodding" mechanism <NUM> can additionally rotate the main reflector <NUM> about a second axis <NUM> that extends into the page to execute a rotational motion. Thus, in some examples, the main reflector <NUM> can be moved linearly and rotated. For example, the main reflector <NUM> can be rotated about axis <NUM> which is positioned at a right side of the main reflector <NUM>. The main reflector <NUM> can thus be rotated in a clockwise direction <NUM> and a counter-clockwise direction <NUM>. The main reflector <NUM> can therefore be rotated relative to the sub-reflector <NUM> and the IPA feed system <NUM>. In some examples, the rotational nodding mechanism <NUM> can be repositioned to be disposed at a central area of the main reflector <NUM> at position <NUM>. In such examples, the main reflector <NUM> would still be rotatable in the clockwise direction <NUM> and the counter-clockwise direction <NUM>.

The movement mechanisms <NUM> can further shift correction (linear and rotation) due to clocking. For example, the movement mechanism <NUM> can include the telescoping boom (e.g., a linear actuator) 214b, a lower gimbal 214c for rotation and/or an upper gimbal 214a for rotation. Thus, the main reflector <NUM> may be further rotated about upper and lower gimbals 214a, 214c, and relative to the sub-reflector <NUM> and the IPA feed system <NUM>. In some examples, the lower gimbal 214c provides a similar or identical rotation to the rotational nodding mechanism <NUM>. In some examples, the lower gimbal 214c is the same as the rotational nodding mechanism <NUM>. In some examples, the lower gimbal 214c rotates the main reflector <NUM> about a different axis than the second axis <NUM>.

<FIG> illustrates a process <NUM> to adjust a confocal antenna. Examples of <FIG> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>) and/or defocused confocal antenna <NUM> (<FIG>). Initially, an IPA feed system <NUM> transmits a beam <NUM> of electromagnetic radiation to a sub-reflector <NUM>. The sub-reflector <NUM> reflects the beam <NUM> from a first position <NUM> of a reflective surface (e.g., a main surface) of the sub-reflector <NUM>. The beam <NUM> is reflected to the main reflector <NUM>, which in turn can reflect the beam <NUM> to a target area to generate a radiation pattern. The beam <NUM> only strikes a portion of the reflective surface of the sub-reflector <NUM> at first position <NUM> and not the entire reflective surface.

Thereafter, the main reflector <NUM> is moved in a linear motion to adjust the radiation pattern. The IPA feed system <NUM> can correspondingly adjust the direction of the beam <NUM> to move the position that the beam <NUM> strikes the reflective surface of the sub-reflector <NUM>. For example, the beam <NUM> now strikes the main reflector <NUM> at a second position <NUM> on the sub-reflector <NUM> and not the first position <NUM>. Doing so can enhance and simplify operations. For example, the IPA feed system <NUM> can employ digital signal processing techniques to adjust the direction of the beam <NUM> to compensate for aberrations that are caused by linearly moving the main reflector <NUM>. Some examples can also include the IPA feed system <NUM> controlling a strength of beam <NUM> and/or size of the beam <NUM> to compensate for aberrations. Some examples can also include only a linear movement of the main reflector <NUM> without rotating the main reflector <NUM> to modify the radiation pattern. As noted, the rotation can be unnecessary as the IPA feed system <NUM> can compensate for the linear movement to generate the radiation pattern in a desired shape. Conversely, some examples can include rotating the main reflector <NUM> without linearly moving the main reflector <NUM>, and adjusting the IPA feed system <NUM> to reduce aberrations.

Examples of <FIG> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>) and/or process <NUM> (<FIG>). <FIG> illustrates an extended position <NUM> of a telescopic boom <NUM> of a confocal antenna having a main reflector <NUM>, as well as a sub-reflector and IPA feed system <NUM>. The main reflector <NUM> is attached to and moved by the extended telescopic boom <NUM>. The telescopic boom <NUM> is adjustable to increase in length and decrease in length to facilitate proper positioning of the main reflector <NUM> relative to the sub-reflector and IPA feed system <NUM>. For example, <FIG> illustrates a retracted position <NUM> of the telescopic boom <NUM>. The telescopic boom <NUM> is fully retracted to decrease a distance between the main reflector <NUM> and the sub-reflector and IPA feed system <NUM>. Other linear adjustment mechanisms can be readily utilized as needed. For example, in some examples the telescopic boom <NUM> can be adjusted in a manner to specified lengths (e.g., in a discrete manner between a limited set of positions), or can be adjusted in a continuous manner (e.g., in a continuous manner to an unlimited set of positions between a maximum and minimum length).

<FIG> illustrates a rotation process <NUM> of the main reflector <NUM>. The main reflector <NUM> is rotated <NUM> around point <NUM> of the telescoping boom <NUM> to adjust transmission vector <NUM> (e.g., a main transmission vector of electromagnetic radiation). <FIG> illustrates the positional final rotation <NUM> of the main reflector <NUM> to change the direction of the transmission vector <NUM>.

<FIG> illustrates an example of a main reflector linear and rotational nodding motion. A small aperture confocal antenna <NUM> is illustrated. A main reflector <NUM> is rotated about rotational point <NUM> along an axis that extends into the page. Telescopic boom <NUM> is extendable along its' axis as well to adjust the position of the main reflector <NUM>. The main reflector <NUM> is additionally rotatable about pivot points <NUM>, <NUM>. A similar configuration can exist with respect to a large aperture antenna.

<FIG> illustrates a confocal antenna <NUM> in more detail. A main reflector <NUM> is attached to a telescopic boom <NUM>. The telescopic boom includes sections 464a-464f that are individually extendable and retractable to adjust the position of the main reflector <NUM>. The telescopic boom <NUM> is able to be moved between a fully retracted position or fully extended position.

Examples of <FIG> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>), process <NUM> (<FIG>), and/or the examples of <FIG>. <FIG> show various radiation patterns that can be generated by examples described herein. <FIG> shows a first case <NUM> with a baseline performance (e.g., nominal position with no main reflector movement without changes to magnification). The "sample element pattern" as used herein is a pattern of one or more elements of an IPA phase array generating a wide beam. "Scanned beams" as used herein are focused and targeted spot beams as described above. The various radiation patterns are examples illustrating distinctions implementing and omitting IPA control as described herein. <FIG>, <FIG>, <FIG> show radiation patterns without corrective IPA control and movements, while <FIG>, <FIG>, <FIG> show radiation patterns with corrective IPA control. Each of <FIG> includes a sample element pattern and two different scanned beams having different characteristics.

<FIG> shows a second case <NUM> with a <NUM>", <NUM> degree linear movement only (e.g., main reflector moved <NUM>" along <NUM> degrees). The "degree linear movement" as described herein and in each example can correspond to the α°, as defined in <FIG>. That is, if this example is applied to <FIG>, the main reflector <NUM> would be moved linearly along the defocusing vector <NUM> for <NUM>", and the defocusing vector <NUM> is separated by <NUM> degrees from the reflector bore sight <NUM>. As illustrated, aberrations occur when implementing the scanned beam (e.g., az: -<NUM>, el: <NUM> and Peak Dir = <NUM>. 38dBi) to cause the scanned beam to be irregularly shaped and not in a desired shape (circular). An IPA feed system can be programmed to compensate for such aberrations by beam steering emitted electromagnetic radiation. The aberrations are undesirable as the aberrations reduce signal quality strength and cause a scattered coverage area that is outside of normal operational parameters.

<FIG> illustrates a third case <NUM> where the main reflector is moved along a <NUM>" linear translation and rotated for <NUM>° (e.g., a rotational nodding). The IPA feed system can adjust for aberrations as described above. In some examples, rotation is bypassed and the IPA feed system adjusts for the aberrations.

<FIG> illustrates a fourth case <NUM> where a main reflector is moved <NUM>" along <NUM> degrees. As illustrated, aberrations occur when implementing the scanned beams. An IPA feed system can adjust for such aberrations as described above by beam forming. <FIG> illustrates a fifth case <NUM> where the main reflector undergoes a <NUM>" linear translation and a <NUM>° rotational nod, and the IPA feed system adjusts for aberrations.

<FIG> illustrates a sixth case <NUM> where the main reflector undergoes a <NUM>" linear translation only along <NUM> degrees. As illustrated, aberrations occur with the scanned beams. <FIG> illustrates a seventh case where the main reflector undergoes a <NUM>" linear translation along <NUM> degrees and <NUM>° rotational nodding, along with IPA feed system adjusting for the aberrations to reduce and/or eliminate the aberrations.

<FIG> illustrates a process <NUM> to shift a main reflector <NUM> by a translation with a rotation. Process <NUM> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>), process <NUM> (<FIG>), examples of <FIG>, and/or examples of <FIG>. Main reflector <NUM> shift correction can be achieved by the use of any combination of the several mechanisms. For example, the main reflector <NUM> is moved along axis <NUM>, and then rotated by a shift mechanism <NUM>. For example, the shift mechanism <NUM> can move along a first axis parallel to axis <NUM> to thereby move the main reflector <NUM> along the axis <NUM>. The shift mechanism can then rotate about a second axis (e.g., extends inward and outward from the page) perpendicular to the first axis to rotate <NUM> the main reflector <NUM>. The examples of <FIG> can be implemented by the main reflector <NUM> and/or shift mechanism.

<FIG> illustrates various mechanisms that can be used to move a main reflector <NUM>. Examples of <FIG> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>), process <NUM> (<FIG>), examples of <FIG>, examples of <FIG> and/or process <NUM> (<FIG>). A rack and pinion <NUM> linearly moves the main reflector <NUM>. A single axis motor <NUM> rotates the main reflector <NUM>. A bi-axial gimbal <NUM> unfurls the main reflector <NUM> from a packed position to an unfurled position when at an appropriate position.

<FIG> shows a method <NUM> of adjusting a confocal antenna. The method <NUM> is generally implemented in a satellite already discussed. Method <NUM> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>), process <NUM> (<FIG>), examples of <FIG>, examples of <FIG>, process <NUM> (<FIG>) and/or examples of <FIG>. In an example, the method <NUM> is implemented in one or more modules as a set of logic instructions stored in a non-transitory machine- or computer-readable storage medium such as random access memory (RAM), read only memory (ROM), programmable ROM (PROM), firmware, flash memory, etc., in configurable logic such as, for example, programmable logic arrays (PLAs), field programmable gate arrays (FPGAs), complex programmable logic devices (CPLDs), in fixed-functionality logic hardware using circuit technology such as, for example, application specific integrated circuit (ASIC), complementary metal oxide semiconductor (CMOS) or transistor-transistor logic (TTL) technology, or any combination thereof.

Illustrated processing block <NUM> controls an IPA feed system to emit electromagnetic energy towards a sub-reflector. The sub-reflector reflects the electromagnetic energy to a main reflector. The main reflector receives and reflects the electromagnetic energy to form a radiation pattern on an area (e.g., on Earth), where the radiation pattern has a first size and a first gain. Illustrated processing block <NUM> conducts an identification that the radiation pattern is to be adjusted. For example, processing block <NUM> determines that the first size is to be adjusted to a second size and the first gain is to be adjusted to a second gain. In response to the identification, illustrated processing block <NUM> moves the main reflector linearly along a first axis, and electronically steers a beam of the electromagnetic energy emitted from the IPA feed system towards the sub-reflector. The method <NUM> can include moving the main reflector relative to the sub-reflector and the IPA feed system along the first axis. The method <NUM> can include in response to the identification, rotating the main reflector along a second axis perpendicular to the first axis. The confocal antenna system can be part of a satellite.

The method <NUM> can include the IPA feed system being an electronically-reconfigurable phased array feed, and adjusting the electromagnetic energy emitted from the IPA feed system to reduce or eliminate one or more aberrations caused by moving the main reflector linearly along the first axis. The method <NUM> can include adjusting emitter phases and/or amplitude and phase of the electromagnetic energy emitted from the IPA feed system to steer the beam. The method <NUM> can include in response to the identification, suppressing an amount of the electromagnetic energy emitted in a first direction from the IPA feed system, and increasing an amount of the electromagnetic energy emitted in a second direction from the IPA feed system.

<FIG> shows a more detailed example of a satellite controller <NUM> that enables adjustments to a confocal feed array fed confocal antenna system. The satellite controller <NUM> can be used in conjunction with any of the examples described herein, such as process <NUM> (<FIG>), defocused confocal antenna <NUM> (<FIG>), process <NUM> (<FIG>), examples of <FIG>, examples of <FIG>, process <NUM> (<FIG>), examples of <FIG> and/or method <NUM> (<FIG>).

The controller <NUM> includes a transmission interface <NUM> to control transmission of signals from an IPA feed system (e.g., data packets), and a reception interface <NUM> to receive signals from ground. The controller <NUM> includes an IPA feed system interface <NUM> to control a direction and strength of electromagnetic energy emitted from the IPA feed system. A mechanical adjustment interface <NUM> facilitates communication and control over one or more mechanisms that move a main reflector. A network controller <NUM> can establish an internet connection with a ground component for communications to transmit messages and receive messages from the ground component. In some examples, the network controller <NUM> can use other modes of communication (e.g., radio) besides an internet connection.

An adjustment controller <NUM> can control a position and rotation of the main reflector through the mechanical adjustment interface <NUM> to control a gain and size of a radiation pattern. A command analyzer <NUM> can receive commands from the on-ground component either through the reception interface <NUM> or the network controller <NUM>. The command analyzer can analyze the commands to determine an appropriate action to execute. For example, the command can indicate that the radiation pattern is to be adjusted and/or change the position of the main reflector. In response, the command analyzer <NUM> can appropriately route the message to the adjustment controller <NUM> to execute the command.

Additionally, the adjustment controller <NUM> includes a processor 914a (e.g., embedded controller, central processing unit/CPU) and a memory 914b (e.g., non-volatile memory/NVM and/or volatile memory) containing a set of instructions, which when executed by the processor 914a, implements any of the aspects as described herein.

Thus, technology described herein supports an enhanced method of communication and particularly dynamic adjustment of a radiation pattern of a satellite. Doing so reduces latency in communications, permits new radiation patterns to be generated on the-fly, and simplifies the process of adjusting the radiation pattern.

Example sizes/models/values/ranges can have been given, although examples are not limited to the same. As manufacturing techniques (e.g., photolithography) mature over time, it is expected that devices of smaller size could be manufactured. In addition, well known power/ground connections to IC chips and other components can or cannot be shown within the figures, for simplicity of illustration and discussion, and so as not to obscure certain aspects of the examples. Further, arrangements can be shown in block diagram form in order to avoid obscuring examples, and also in view of the fact that specifics with respect to implementation of such block diagram arrangements are highly dependent upon the computing system within which the example is to be implemented, i.e., such specifics should be well within purview of one skilled in the art. Where specific details (e.g., circuits) are set forth in order to describe example examples, it should be apparent to one skilled in the art that examples can be practiced without, or with variation of, these specific details. The description is thus to be regarded as illustrative instead of limiting.

The term "coupled" can be used herein to refer to any type of relationship, direct or indirect, between the components in question, and can apply to electrical, mechanical, fluid, optical, electromagnetic, electromechanical or other connections. In addition, the terms "first", "second", etc. can be used herein only to facilitate discussion, and carry no particular temporal or chronological significance unless otherwise indicated.

Claim 1:
A confocal satellite antenna system comprising:
an Integrated Phased Array, IPA, feed system (104c, <NUM>, <NUM>, <NUM>) to emit electromagnetic energy;
a sub-reflector (104b, <NUM>, <NUM>) to reflect the electromagnetic energy;
a main reflector (104a, <NUM>, <NUM>, <NUM>), to receive and reflect the electromagnetic energy to form a radiation pattern on an area, wherein the radiation pattern has a first size and a first gain;
at least one processor (914a); and
at least one memory (914b) coupled to the at least one processor (914a), the at least one memory (914b) including a set of instructions, which when executed by the at least one processor (914a), causes the confocal antenna system to:
receive an instruction from a ground component that the radiation pattern is to be adjusted so as to adjust the first size to a second size and adjust the first gain to a second gain; and
in response to the instruction,
move the main reflector (104a, <NUM>, <NUM>, <NUM>) linearly along a first axis perpendicular to the reflective surface of the main reflector, and
electronically steer a beam of the electromagnetic energy emitted from the IPA feed system (104c, <NUM>, <NUM>, <NUM>) towards the sub-reflector (104b, <NUM>, <NUM>).