Abstract: A wireless communication apparatus includes multiple antennas, a receiver for performing diversity reception using the antennas, a transmitter, a selector circuit connected to the antennas, a divider, and a phase shifter. The divider is located in a transmission line which connects the selector circuit to the transmitter and distributes a signal outputted from the transmitter among the antennas during transmission. The phase shifter is located in at least one of multiple transmission lines, each of which connects the divider to a corresponding one of the antennas.

Abstract: A hybrid satellite antenna comprises an ESA with two steerable dimensions connected to a motor. The motor rotates the antenna about an axis to position the antenna such that a satellite signal can be sufficiently resolved using the two steerable dimensions of the ESA.

Abstract: A portable motorized satellite television antenna system is connectable to a separate receiver. The satellite television antenna system can include an enclosure with at least a portion thereof comprising an electromagnetic wave permeable material. A reflector dish can be disposed inside of the enclosure. A low noise block converter can be disposed inside of the enclosure and configured to receive incoming satellite television signals. A first drive motor can be coupled to the satellite television antenna system such that at least one of an azimuth orientation and an elevation orientation of the dish can be adjusted. An electronic control system disposed inside of the enclosure and connected to the first drive motor to control automated aiming of the dish. The electronic control system and first drive motor can be powered solely by the separate receiver though a single conduit that spans between the satellite antenna system and the receiver.

Abstract: A scan alignment system and method for calibrating a scan path for a directional antenna system is presented. The scan alignment system calibrates the scan path by generating a scan path, scanning the directional antenna through the scan path, receiving a signal signature responsive to the scanning, comparing the signal signature with a reference signature, and determining a corrective calibration to apply to the scan path that minimizes the difference between the signal signature and the reference signature. In an embodiment, the reference signature is modeled based on the directional antenna and the intended scan path.

Abstract: One embodiment of the present invention sets forth a technique for transmitting data in a frequency hopping spread spectrum (FHSS) wireless communication system. A multi-channel receiver is configured to receive data from one or more channels simultaneously. The multi-channel receiver enables efficient implementation of a transmission protocol in which multiple candidate nodes within a wireless mesh network are polled for availability to receive a packet of data. The packet of data is transmitted to one or more available nodes based on prevailing link conditions, thereby increasing the likelihood of successful delivery. Data flooding may be selectively implemented to further increase the likelihood of successful delivery.

Abstract: A service-ability system determines a probability of a proper installation of satellite broadcast reception equipment at a given location. A method for determining service-ability comprises accessing data related to a given location via a computer, assigning a weight and a value to each accessed data point with the computer, compiling the values of each accessed data point, and comparing the compiled values to a predetermined probability threshold.

Abstract: A system for broadcasting and receiving a beacon signal includes a beacon transmitter (310, 400) and a beacon receiver (320, 500). The beacon transmitter includes a beacon signal generator (410) to generate a beacon signal, and a directional antenna system (420) to selectively transmit the beacon signal in a corresponding one of M different directions during each one of M beacon slots (342) during a beacon period (340) in each of a plurality of superframes (330). The beacon receiver includes a beacon signal detector (510) to receive and detect the beacon signal, and a directional antenna system (520) having an antenna pattern including a main lobe and being adapted to selectively steer the main lobe in a selected one of N different directions during each of a plurality of receiver frames each having a time period substantially equal to a time period of one of the superframes.

Abstract: A method, apparatus, system, and computer program product for auto-installing an integrated receiver/decoder (IRD) includes issuing an auto-installation command from the IRD to an outdoor unit (ODU) and receiving a plurality of tones from the ODU in response to the auto-installation command, each tone representing a center frequency of available user bands (UBs). The auto-installation also includes acquiring a UB center frequency by the IRD, requesting the ODU to confirm a UB number corresponding to the acquired UB center frequency, and receiving confirmation from the ODU that a UB number corresponds to the acquired UB center frequency. The auto-installation also includes sending an acceptance of the assigned UB number from the IRD to signal the ODU that it may mark the assigned UB as assigned.

Abstract: A system incorporating the subject disclosure may include, for example, a method including determining, by a communication device comprising a processor, a usage state of the communication device. The communication device includes selectable antennas, and the usage state includes an orientation of the communication device. The method also includes selecting a set of antennas according to the usage state, and obtaining an antenna gain pattern for an antenna in the selected set of antennas. The method further includes evaluating an expected performance of an antenna configuration corresponding to the selected set of antennas, relative to a performance of an existing antenna configuration. The method also includes initiating usage of the antenna configuration in accordance with improved performance relative to the existing antenna configuration. The antenna configuration comprises a polarization configuration, and the selected set of antennas comprises elements in different planes.

Abstract: A stabilization control method for a satellite tracking antenna disclosed herein includes outputting a monopulse signal and a gyro signal through a satellite tracking antenna having a gyro mounted thereto, under a situation that disturbance is applied to the satellite tracking antenna, inputting the output monopulse signal and gyro signal into a Kalman filter for stabilization of the satellite tracking antenna, defining a state vector of the Kalman filter based on a pointing-error angle for the satellite tracking, corresponding to the monopulse signal, and a pointing-error angular velocity for the satellite tracking, corresponding to the gyro signal, predicting an original monopulse signal corresponding to a state prior to distortion of the monopulse signal based on the defined state vector, and continuously updating the prediction of the original monopulse signal, and carrying out the stabilization control for the satellite tracking antenna by using the predicted original monopulse signal as a pointing-error

Abstract: A Communications base-station configured to operate as a hub in a wireless network and provide communication services to a set of remote customer devices using a wireless protocol is disclosed. The communications base-station includes an antenna array having a plurality of antennae arranged in a fashion as to enable the antenna array to transmit and receive wireless signals in both a substantially omnidirectional and non-omnidirectional pattern, a physical layer (PHY) device coupled to the antenna array and configured to transmit and receive wireless signals and a media access control (MAC) device coupled to the PHY device and configured to direct the antenna array to concurrently provide beamformed wireless signals to a first customer device and omnidirectional wireless signals to second customer device.

Abstract: An interference reduction system is operable to reduce interference experienced by one or more antennas. The system detects the presence of one or more interference signals. The system then causes an antenna's radiation pattern to change. The change in the radiation pattern results in a reduction in interference.

Abstract: A communication system including a plurality of horn antennas, a waveguide feed network, and a converter unit coupled to the plurality of horn antennas is disclosed. The waveguide feed network is coupled to each horn antenna, splits an information signal into a first component signal having a first polarization and a second component signal having a second polarization and provides a first summed component signal at a first feed port and a second summed component signal at a second feed port. The converter unit receives the first summed component signal and the second summed component signal and compensates for polarization skew between the antenna array and a source.

Abstract: An alignment device provides position information for an antenna coupled to an extendable tower. The alignment device can provide position data including pitch data, roll data, and azimuth data. The position data can be collected at multiple times, and reported to a remote computing device. The position data can be reported as the raw measured data, a delta between two sets of position data, or other data. The alignment device may be solar powered and include a transceiver client for communicating with a remote computing device via a transceiver server.

Abstract: A user-controlled method for modifying the radiation of a wireless device (1) in one or more volumes used for in-house communications, comprising user-selecting this one or more volumes (10, 10?, 10?, 10??, 10IV) while holding the orientation of this wireless device (1) modifying the intensity of this radiation in one or more directions so as to control the radiation in this user-selected one or more volumes (10, 10?, 10?, 10??, 10IV). The invention allows the user to define volumes or regions where radiation should be modified, e.g. reduced, and one or more temporal intervals in which this radiation should be reduced.

Abstract: Systems and methods for determining a positional state of an airborne array antenna using distributed accelerometers are described.

Abstract: A system and method of training antennas for two devices having heterogeneous antenna configurations in a wireless network is disclosed. The method includes communicating one or more estimation training sequences between two devices via a phased array antenna and a switched array antenna, wherein a beamforming vector of the phased array antenna is switched between phase vectors within a set of weight vectors while the switched array antenna is switched within a plurality of antenna sectors. The method further includes tuning at least one of the phase array and switched array antennas with an antenna parameter selected based at least in part on the one or more estimation training sequences. The method further includes communicating data messages via at least one of the phase array and switched array antennas so tuned.

Abstract: An in-flight entertainment (IFE) system for an aircraft includes a phased array antenna and control circuitry associated therewith to be carried by the aircraft and to generate dual antenna beams for television programming and Internet data from respective spaced apart satellites. A television programming distribution system is to be carried by the aircraft and coupled to the phased array antenna and control circuitry to provide television programming within the aircraft. At least one access point is to be carried by the aircraft and coupled to the phased array antenna and control circuitry to provide a wireless local area network (WLAN) within the aircraft for the Internet data.

Abstract: Some demonstrative embodiments include devices, systems and/or methods of wireless communication via multiple antenna assemblies. For example, a device may include a wireless communication unit to transmit and receive signals via one or more quasi-omnidirectional antenna assemblies, wherein the wireless communication unit is to transmit, via each quasi-omnidirectional antenna assembly, a plurality of first transmissions, to receive, in response to the first transmissions, a plurality of second transmissions from another device via one or more of the quasi-omnidirectional antenna assemblies, and, based on the second transmissions, to select at least one selected transmit antenna assembly for transmitting to the other device and a selected receive antenna assembly for receiving transmissions from the other device. Other embodiments are described and claimed.

Abstract: For determining the topology of a bulk material surface, a series of echo curves are detected in different primary radiation directions of the antenna. Subsequently, for each distance cell of the echo curves, the maximum of all of the echo curves is determined and the distance thereof is plotted as a function of the coordinates thereof so as to obtain an image of the topology of the bulk material surface in two or three dimensions.

Abstract: A normality detector includes a steering angle yaw rate calculator, a first difference calculator, a lateral G yaw rate calculator, a second difference calculator, and a normality determination section. The steering angle yaw rate calculator calculates a steering angle yaw rate. The first difference calculator calculates a first difference which is a difference between the steering angle yaw rate and an actual yaw rate. The lateral G yaw rate calculator calculates a lateral G yaw rate. The second difference calculator calculates a second difference which is a difference between the lateral G yaw rate and the actual yaw rate. The normality determination section determines that the yaw rate detector is in a normal state when the first difference falls within a first predetermined value and the second difference falls within a second predetermined value.

Abstract: A radar system that includes a gimbal and a platform secured to a frame through the gimbal is disclosed. The radar system includes an antenna rotatably supported by the platform for rotation about an axis and configured to scan a hemispherical field of view above the platform. A controller that controls the rotation of the antenna and a gyroscopic stabilizer that is secured to the platform to maintain the platform in a stable and level position during operation of the radar system and rotation of the antenna is also disclosed. A vehicle is also disclosed for traversing a geographic region with the radar system. The antenna may transmit in the X band. A telescoping mast having a first end secured to the platform and having a second end secured to the gimbal is also disclosed.

Abstract: Multipoint wireless communications are coordinated in cells with radiation that is emanated from antennas in an inward direction. In an example embodiment, an apparatus includes a first antenna, a second antenna, a third antenna and a controller. The first antenna emanates radiation from a first location in an inwardly direction for a cell. The second antenna emanates radiation from a second location in an inwardly direction for the cell. The third antenna emanates radiation from a third location in an inwardly direction for the cell. The controller coordinates the emanation of the radiation via the first, second, and third antennas so as to reduce intra-cell interference for remote terminals located within the cell. The coordination may be effected in accordance with one or more coordinated multi-point (transmission/reception) (CoMP) techniques. Different numbers of sub-cells and antennas per cell and different CoMP cell organizations may be implemented.

Abstract: The present invention discloses a communication antenna automatic orientation apparatus and method, wherein the apparatus comprises: a target base station geographical storage for storing the corresponding relation between the spatial location information on the air lane and the identifier of a target base station; a sensor for confirming current spatial location information of the aircraft; an aircraft spatial orientation sensor for confirming a current spatial orientation of the aircraft; a master controller for confirming a target direction of a directional antenna according to the current spatial location information, the corresponding relation and the current spatial orientation and sending an instruction carrying the target direction; an automatic antenna directional system for receiving the instruction and driving the directional antenna according to the target direction so as to enable the directional antenna to receive a signal from a ground base station in the target direction; a wide aperture anten

Abstract: A method of optimizing an antenna system can include determining a desired angle to rotate an antenna based on an axial ratio of electromagnetic waves exiting a radome that surrounds the antenna. The desired angle can be determined by a computing device based on a set of axial ratio values.

Abstract: A Master Antenna Controller System is provided. In one example, the Master Antenna Controller System comprises a handheld wireless device and a RET Master. The handheld wireless device may comprise an Android OS or iOS based smartphone or tablet that includes Wi-Fi capabilities communications capabilities. The RET Master may provide full RET control based on the AISG 1.1 and 2.0 standards and communicate with the handheld wireless device via a wireless access point, such as a Wi-Fi server. The combination may be configured to provide extensive, screen-guided, intuitive RET diagnostics functionality. The RET Master itself may also include multiple different pre-defined tests (e.g. test one actuator, test one RET cable, test AISG signal from TMA) and also some standard electrical tests, e.g. measuring voltage, current etc. Additional higher-level functions may be provided on an Application on the handheld wireless device and communicated to the RET Master wirelessly or by USB connection.

Abstract: A horizontal beam adjusting method and apparatus for an omni-directional antenna are provided. The horizontal beam adjusting apparatus may generate a switch control signal according to an inclination of the omni-directional antenna, and adjust a radiation direction of the omni-directional antenna according to the switch control signal. Accordingly, the adjusted radiation direction may have horizontal omni-directionality with respect to a ground surface.

Abstract: A system and method to provide a means of communication, command and control between a mobile antenna and a satellite receiver that allows the receiver to send tuning information to the antenna and the antenna to provide feedback to the receiver when a signal has been acquired. The antenna and the receiver can share the appropriate states and status such as diagnostics, test, GPS coordinates, etc.

Abstract: Method, device and computer readable memory aspects describe aligning antennas such as short range communication antennas in communication devices that may be used to transmit and receive electrical power for device charging. A measure of antenna alignment may be determined in response to electrical power received by one of the antennas. A suggested movement is determined for moving at least one of the antennas (e.g. the communication device housing the antenna) for increasing the measure of antenna alignment and the suggested movement is presented in a graphical user interface (GUI). Movement may be suggested along a first plane to maximize antenna alignment followed by movement along a second plane to further maximize antenna alignment. A map may be defined from measured antenna alignment values and movement suggested in response to the map. Maximized antenna alignment may be signalled (e.g. vibration) when the measure of alignment is within a threshold range.

Abstract: A direction finding system for finding the angle of arrival of a target signal from a transmitter. The system includes a plurality of directional antennas positioned to face different directions for receiving the target signal. The antennas are mounted as an antenna array on a rotatable mount for supporting and rotating the antenna array. A receiver unit down converts the RF target signal to IF signals that are digitized by an A/D converter providing digital values. A computer computes the power in the signals from the A/D samples. A computer stores calibration information for the directional antennas, processes the digital values and the calibration information to determine a rotation angle ? for rotating the antennas to provide new digital values, processes the new digital values and the calibration information to determine an intersection angle, and subtracts the rotation angle from the intersection angle to determine the final value for the angle of arrival of the target signal.

Abstract: The present invention is directed to systems and methods for enhancing link integrity between two wireless cable devices through automatic link acquisition and tracking. Embodiments of the invention utilize inexpensive motors and control components to automatically enhancing signal strength between a first wireless cable device and a second wireless cable device. Either the first wireless cable device, the second wireless cable device, or both may include an omnidirectional wireless antenna. Alternatively, the first wireless cable device, the second wireless cable device, or both may include a directional antenna. In another embodiment, the first wireless cable device, the second wireless cable device, or both may include both an omnidirectional antenna and a directional antenna.

Abstract: An apparatus and methods are provided to realize an input waveform using wavelet processing and reconstruction via separated antenna array systems having different beam paths and different frequency components which can include phased array transmitters to recreate the input waveform. One aspect of the invention can include a wavelet function used for the examples shown herein which includes a first and second moments of a statistical function, i.e. the mean and variance used with an inverse wavelet to create rectangular pulses that lend themselves to use in the invention herein. Other embodiments of the invention can use other input waveform separation functions paired with signal separation and recombination at a focus point. A selected function can be matched to its application associated with avoidance of sending the input waveform along a single beam path, a desired a focus point, and separation of an input signal.

Abstract: A system and method for imaging and aligning antennas that includes an overlay imaging aligner composed of two or more antennas in association with a polarization gate, a polarization beam splitter, a non-polarizing beam splitter, a beam dump, one or more imaging lens and a common detector array. The overlay imaging aligner aligns the antennas by overlaying simultaneous digital images associated with the antennas on the common detector array. The antennas can be, for example, mm Wave antennas, waveguides, etc. The detector array generates real-time digital images the antennas. Such an approach of simultaneous imaging leverages the spatial resolution of digital optical imaging to aligning antenna components.

Abstract: The system comprises an orientable block, in which are mounted at least transmission and reception antennas of means for detecting improvised explosive devices, which are directed in such a way as to illuminate at least one and the same zone of space, and a detection confirmation camera which is directed towards the zone illuminated by these transmission and reception antennas in such a way as to be able to form an image of this zone, as well as means for controlling the orientation of said orientable block, which bring about a displacement of said block in such a way as to generate a scan of a part of space by said detection means.

Abstract: Embodiments disclosed herein relate to a communication system. Particularly disclosed are systems and methods for locating and tracking radio frequency signals and for automatically positioning an antenna to receive a desired radio frequency signal. The system may comprise an antenna module comprising a receive antenna and a plurality of tracking antennas, a base, one or more motors configured to rotate the antenna module and/or tilt the receive antenna relative to the base, and processing circuitry. The processing circuitry may include a spectrum analyzer and may be configured to receive inputs from the tracking antennas and provide outputs to control the motors.

Abstract: An effective marine stabilized antenna system, in terms of antenna to radome size and antenna/RF performance complies with all relevant worldwide SatCom regulations. The combination of a dual offset Gregorian antenna (DOGA) with a stabilized polarization over elevation over tilt over azimuth pedestal, and a control/stabilization algorithm, ensures antenna orientation restrictions guarantee compliance with side-lobe intensity regulations. Operating a dual offset Gregorian antenna substantially within a pre-determined antenna cut range of a 45 degree angle relative to a configuration of the antenna and a relative position of a target provides antenna performance that complies with applicable SatCom regulations, despite having to flip the antenna 90 degrees to continue tracking the satellite.

Abstract: A system and method for automatically coordinating different remote broadband communications sources using multiple directional antennas mounted on a single vehicle and automatically tracking the signal sources in accord with the coordination. The system scans the horizon to identify all available signals being respectively received from the plurality of remote broadband wireless communication sources. The signals or sources are then ranked based on an optimization criteria. Based on the criteria, a first directional antenna is positioned to allow two-way communication with the first remote broadband communication source and the second directional antenna is positioned to allow two-way communication with the second remote broadband communication source.

Abstract: A method for access or starting verification for a vehicle using a mobile identification encoder and at least two antennas located in or on the vehicle at different locations includes: the antennas emitting electromagnetic signals at alterable times, wherein the electromagnetic signals are emitted in transmission blocks having alterable specific properties and wherein a plurality of transmission blocks are strung together to form a communication message in which each transmission block adopts an alterable position in time, the identification encoder receiving the electromagnetic signals emitted by the antennas and processing them to generate a response signal, and altering at least one of the times at which the individual antennas are actuated, the specific properties of the individual transmission blocks, and the position of the individual transmission blocks in time in the communication message in accordance with a cryptographical method.

Abstract: A communication device is described comprising an antenna arrangement, an orientation determining device configured to determine the orientation of the antenna arrangement, and a controller configured to control the directivity of the antenna arrangement based on the determined orientation of the antenna arrangement.

Abstract: Systems and methods for antenna pointing are disclosed. A transmit antenna system having an adjustable boresight transmits a signal exhibiting a far-field pattern including a feature (e.g. a V-Notch) in a polarization of the signal disposed at a fixed position off a beam peak of the far-field pattern of the signal. A receive antenna system scans across the far-field pattern of the signal in the polarization to locate the feature and determine a pointing error of the adjustable boresight therefrom. The system may be applied to a cross-polarization of the signal where a co-polarization of the signal is simultaneously used for telecommunication.

Abstract: Apparatuses and methods for maintaining an optimal beam direction in a wireless communication system are provided. The method for operating a receiving node in a wireless communication system includes, determining a first transmission beam is determined as a preferred transmission beam using a plurality of reference signals transmitted by a transmitting node, generating preferred transmission beam information, transmitting the preferred transmission beam information to the transmitting node, receiving transmissions from the transmitting node via the first transmission beam, and determining whether a change of a transmission beam is necessary. When the change of the transmission beam is determined to be necessary, generating a beam change request and transmitting the beam change request to the transmitting node.

Abstract: A system is provided to establish and maintain a data path between a Local Area Network (LAN) that is mounted on a moving vehicle and a satellite. In combination, an antenna assembly, an Antenna Control Unit (ACU), an Inertial reference Unit (IRU), and a modem are mounted together on the moving vehicle, under the overall control of a services platform. Operationally, the IRU generates parametric values indicative of the spatial attitude and location of the moving vehicle. The ACU then uses the parametric values to aim the antenna in a direction toward the satellite. In this combination, the modem is connected with the antenna to transmit and receive data between the system and the satellite. Individually or collectively, operationally compatible components of the system (IRU, ACU, antenna and modem) can be appropriately substituted to thereby customize the system.

Abstract: A directional antenna system for portable communication device that provides user control on the transmit antennas. The directional antenna system is made by two or more directional antennas with the directional antennas arranged in the pattern such that one of the directional antenna is pointing towards the user and the other directional antenna(s) are pointing away from the user. The directional antenna system is designed to cover a 360 degree circle in both the receiving and transmitting mode. In one of the transmitting mode, the portable communication device transmits RF signal on the directional antenna(s) that is pointing away from the user to minimize the electromagnetic energy exposure to the user. In the case when the RF receiving signal is below the desired operating condition on the outward pointing directional antenna(s), the portable communication device will generate an alert to the user.

Abstract: A satellite communication ground station configured for communicating over an inclined orbit geostationary satellite may include a tracking antenna having three fixed axis and one moving axis, a motor for swinging the antenna along the moving axis, a controller for controlling the motor, a receiver configured to receive a signal arriving from the satellite via the tracking antenna and an estimator configured to estimate reception quality of a signal received by the receiver. The invention described herein presents a method for tracking an inclined orbit geostationary satellite, the method comprising a learning step and a tracking step, wherein the learning step includes use of a filter for reducing alignment errors and reducing the amount of peaking required for aligning the antenna with the satellite and tracking its movement.

Abstract: An app running on a communication device determines a current position of an antenna, which is to be aligned with a transmitter. The app determines a direction in which the antenna should be oriented so that the antenna is aligned with the transmitter when the communication device is placed by the antenna. The app may generate, based on the determined direction, one or more cues to enable alignment of the antenna so that the current position or a newly determined current position of the antenna is aligned with the determined position of the transmitter. The cues may include audible, visual and/or vibration cues. The app may acquire information from one or more sensors, which are located within the communication device and/or integrated within the antenna. The acquired information may be utilized to determine the current position and/or a newly determined current position of the antenna.

Abstract: A signal reception assembly may be installed by a user, and configured to achieve optimal alignment (e.g., perfect or near-perfect alignment) with a particular signal source. The signal reception assembly may receive signals from the signal source, and signal related information may be determined based on processing of the received signals, with the signal related data comprising parameters pertinent to configuring reception of signals from the particular signal source. An electronic device may be coupled to the signal reception assembly, and may be utilized to obtain and/or determine positioning information which may correlate with the positing of the signal reception assembly. Adjustments to aiming and/or alignment of the signal reception assembly, relative to the particular signal source, may be determined based on the positioning information and the signal related data to achieve the optimal alignment.

Abstract: An antenna control system enabling the remote variation of antenna beam tilt. A drive means continuously adjusts phase shifters of a feed distribution network to radiating elements to continuously vary antenna beam tilt. A controller enables the beam tilt of a number of antenna at a site to be remotely varied.

Abstract: Some demonstrative embodiments include devices, systems and/or methods of wireless communication via multiple antenna assemblies. For example, a device may include a wireless communication unit to transmit and receive signals via one or more quasi-omnidirectional antenna assemblies, wherein the wireless communication unit is to transmit, via each quasi-omnidirectional antenna assembly, a plurality of first transmissions, to receive, in response to the first transmissions, a plurality of second transmissions from another device via one or more of the quasi-omnidirectional antenna assemblies, and, based on the second transmissions, to select at least one selected transmit antenna assembly for transmitting to the other device and a selected receive antenna assembly for receiving transmissions from the other device. Other embodiments are described and claimed.

Abstract: Methods, systems, and computer-readable media are described herein for using a modified Kalman filter to generate attitude error corrections. Attitude measurements are received from primary and secondary attitude sensors of a satellite or other spacecraft. Attitude error correction values for the attitude measurements from the primary attitude sensors are calculated based on the attitude measurements from the secondary attitude sensors using expanded equations derived for a subset of a plurality of block sub-matrices partitioned from the matrices of a Kalman filter, with the remaining of the plurality of block sub-matrices being pre-calculated and programmed into a flight computer of the spacecraft. The propagation of covariance is accomplished via a single step execution of the method irrespective of the secondary attitude sensor measurement period.

Abstract: A directional antenna system for an aircraft is disclosed. The directional antenna system may include an enclosure, a linear antenna array disposed within the enclosure and a controller. The linear antenna array may include a plurality of antenna elements physically oriented in the same orientation. The plurality of antenna elements may be positioned along a longitudinal axis of the aircraft and spaced apart from each other by a predetermined distance center-to-center. The controller may be in communication with each of the plurality of antenna elements of the linear antenna array. The controller may be configured for independently controlling a RF phase angle of each of the plurality of antenna elements based on a position of the aircraft and at least one ground station available to the aircraft, allowing the linear antenna array to concentrate RF radiations in a particular wavelength toward a general direction.