WO2003007420A1 - System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof - Google Patents

System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof Download PDF

Info

Publication number
WO2003007420A1
WO2003007420A1 PCT/US2002/021814 US0221814W WO03007420A1 WO 2003007420 A1 WO2003007420 A1 WO 2003007420A1 US 0221814 W US0221814 W US 0221814W WO 03007420 A1 WO03007420 A1 WO 03007420A1
Authority
WO
WIPO (PCT)
Prior art keywords
antenna
position location
elevation
information
transceiver
Prior art date
Application number
PCT/US2002/021814
Other languages
French (fr)
Other versions
WO2003007420A8 (en
Inventor
Samir S. Soliman
Ernest T. Ozaki
Peter Gaal
Original Assignee
Qualcomm Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US10/071,928 external-priority patent/US6690917B2/en
Application filed by Qualcomm Incorporated filed Critical Qualcomm Incorporated
Priority to AU2002320390A priority Critical patent/AU2002320390A1/en
Priority to MXPA04000347A priority patent/MXPA04000347A/en
Priority to KR1020047000435A priority patent/KR100924245B1/en
Publication of WO2003007420A1 publication Critical patent/WO2003007420A1/en
Publication of WO2003007420A8 publication Critical patent/WO2003007420A8/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
    • G01S3/14—Systems for determining direction or deviation from predetermined direction
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/02—Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
    • G01S3/14—Systems for determining direction or deviation from predetermined direction
    • G01S3/38—Systems for determining direction or deviation from predetermined direction using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal
    • G01S3/42—Systems for determining direction or deviation from predetermined direction using adjustment of real or effective orientation of directivity characteristic of an antenna or an antenna system to give a desired condition of signal derived from that antenna or antenna system, e.g. to give a maximum or minimum signal the desired condition being maintained automatically
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/125—Means for positioning
    • H01Q1/1257—Means for positioning using the received signal strength
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/246—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for base stations
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/02—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical movement of antenna or antenna system as a whole
    • H01Q3/08—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical movement of antenna or antenna system as a whole for varying two co-ordinates of the orientation

Definitions

  • the present invention relates generally to the field of wireless communications and, in particular, to an automatic antenna directing system capable of accurately pointing a wireless communication directional antenna at a desired transceiver.
  • Wireline solutions which include cable network services and Digital Subscriber Line (DSL) services, offer relief to subscribers having access to such services. Because of the relatively high capital expenditures and labor costs associated with providing connectivity and access to new regions, these services are far from ubiquitous.
  • DSL Digital Subscriber Line
  • wireless solutions are more cost effective and may service a wider range of subscribers.
  • These wireless solutions are based on high-speed wireless data communication systems that employ either satellite-based data networks, such as, for example, DirecPC and StarBand services, or terrestrially-based data networks, such as cellular data networks.
  • satellite-based data networks such as, for example, DirecPC and StarBand services
  • terrestrially-based data networks such as cellular data networks.
  • these high-speed wireless data communication systems are power limited hence contemplate the use of a high-gain, narrow beam, highly-directional fixed antenna coupled to a user terminal to deliver information to a subscriber.
  • these fixed user antennas generally manifest stringent alignment requirements. That is, to ensure adequate communication capabilities, the user transmit or receive antennas need to accurately point in the direction of their counterpart antennas for both transmit and receive operations.
  • link budgets have small margins, hence user antennas need to point to a satellite along specific elevation and azimuthal directions in order to maximize the gain of the received beam pattern and, thus, ensure optimal data transmission.
  • user antennas need to be aligned along specific elevation and azimuthal directions to point to the radiation center of a cellular antenna arrangement to ensure maximum possible signal-to-noise ratio. It will be appreciated that, although the specific location of both the user antenna and satellite antenna or cellular antenna may be known, such information does little to identify the exact orientation of the user antenna.
  • the system includes a position location receiver, which receives signals indicating position location information of the antenna and a position location transmitter.
  • a processing mechanism coupled to the position location receiver determines calibration information of the antenna based on the location information of the antenna and the position location transmitter.
  • An alignment mechanism coupled to the processing mechanism and the antenna, automatically orients the antenna, based on the calibration information, and automatically directs the oriented antenna to point to the wireless transceiver, based on the directional location information of the wireless transceiver.
  • Additional aspects of the present invention include determining the calibration information by first accurately pointing to the position location transmitter via a direction finding mechanism and then establishing a vector reference space. The necessary elevation and azimuthal components, within the vector reference space, are then calculated to identify the proper calibration of the antenna. Once the calibration information has been determined, an alignment mechanism automatically orients the antenna and, based on the directional location information of the wireless transceiver, alignment mechanism automatically directs the oriented antenna to point to the wireless transceiver. BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1A illustrates a functional block diagram of an automatic antenna directing system, constructed and operative in accordance with an embodiment of the present invention
  • FIG. IB illustrates a functional block diagram of an automatic antenna directing system in a satellite network application, constructed and operative in accordance with another embodiment of the present invention
  • FIG. 1C illustrates a functional block diagram of an automatic antenna directing system in a terrestrial network application, constructed and operative in accordance with another embodiment of the present invention
  • FIG. ID illustrates beam patterns as functions of gain and azimuthal angles, in accordance with another embodiment of the present invention.
  • FIG. 2A depicts a functional flow chart diagram of an automatic directing process, constructed and operative in accordance with an embodiment of the present invention.
  • FIG. 2B depicts a spatial vector reference diagram in accordance with an embodiment of the present invention.
  • a system for automatically directing a user antenna that accurately points to a desired communication transceiver may be employed to ensure adequate performance of high-speed data communication networks.
  • the system exploits the position location information between a position location receiver and a position location transmitter to generate a reference vector and a corresponding vector reference space. Because the position location information only contains location information and cannot render orientation information of the* user antenna, the reference vector and vector reference space are used as a frame of reference to facilitate the deduction of orientation information (e.g., elevation and azimuthal direction information). This orientation information is then used to calibrate and properly orient the user antenna.
  • orientation information e.g., elevation and azimuthal direction information
  • the user antenna may then be aligned to point to the desired communication transceiver based on the position location information of the transceiver or other methods.
  • An antenna alignment mechanism then automatically adjusts the user antenna to point to the transceiver based on the user and the transceiver location information.
  • FIG. 1A illustrates an automatic antenna directing system 100, constructed and operative in accordance with an embodiment of the present invention.
  • wireless communications such as, for example, filters, duplexers, amplifiers, and up/down converters that are ancillary to the present invention have been omitted.
  • Antenna directing system 100 may be used in conjunction with the high-speed wireless data communication services.
  • the high-speed wireless data communication services may be provided by either a satellite- based or terrestrially-based data communication network.
  • system 100 employs a user terminal 108, which is coupled to a user communication antenna 102A.
  • User antenna 102A communicates with a network communication transceiver mechanism 112 via a network communication antenna 110.
  • User terminal 108 may include a processing mechanism 108A configured to execute program instructions residing in system memories.
  • System 100 further comprises a user communication transceiver mechanism 104 coupled to both user terminal 108 and user communication antenna 102A.
  • user transceiver mechanism 104 is configured to modulate and up-convert the baseband data into a form suitable for subsequent radiation by user communication antenna 102A.
  • user transceiver mechanism 104 is configured to demodulate and down-convert the signals received by user communication antenna 102A into baseband data.
  • User antenna 102A may also comprise alignment mechanism 105, capable of aligning antenna 102A along the elevation and azimuthal directions.
  • Alignment mechanism 105 may comprise motorized components and associated circuitry to align antenna 102A along the proper directions once the elevation and azimuthal directional information have been resolved. To this end, alignment mechanism 105 may receive control signals from processing mechanism 108A to drive the motorized components and align antenna 102A along the proper directions.
  • System 100 may further comprise a position location receiver 106, such as, for example, a Global Positioning System (GPS) receiver or similar navigation/position location receiver, and an associated position location antenna 102B.
  • Position location receiver 106 is configured to process and provide antenna 102B location information from at least one geostationary satellite capable of rendering position location services. Such information may be based on GPS or similar navigation/position location systems, which employ a plurality of position location transmitters (e.g., 3 or more) to yield accurate position location information. Consistent with navigation/position location systems, these transmitters may be configured as orbiting satellites (e.g., GPS satellites).
  • GPS Global Positioning System
  • user communication antenna 102A may also serve as position location antenna 102B or may be integrated with position location antenna 102B to form integrated antenna 103 that functions as both a communication and position location antenna.
  • alignment mechanism 105 may be used in conjunction with the position location functionality to provide directional finding capabilities for tracking the position location transmitters.
  • FIG. IB illustrates an automatic antenna directing system 125 operative with a high-speed, satellite-based data communication network, in accordance with an embodiment of the present invention.
  • antenna directing system 125 employs an integrated user antenna 103, which communicates, via a satellite network antenna 110A, with a satellite network transceiver 112A (e.g., transponder) to effect the transmission of the high-speed data.
  • user antenna 103 radiates a narrow transmit beam pattern for the transmission of data to satellite antenna 110A and collects a receive beam pattern from satellite antenna 110A for the reception of data.
  • user antenna 103 is depicted as a microwave dish antenna, it will be appreciated that other antenna configurations may be employed.
  • Antenna directing system 125 further comprises a position location receiver 106, coupled to user antenna 103.
  • user antenna 103 may be configured to also receive position location information from a position location transmitter 114.
  • position location information may be based on GPS or similar navigation/position location systems, employing a plurality of position location transmitters (e.g., 3 or more), which may configured as orbiting satellites (e.g., GPS satellites).
  • Position location transmitter 114 may be configured to furnish, on a predetermined basis, data detailing timing information and ephemeris data indicating the position location of transmitter 114.
  • the position location of satellite transceiver 112A, as well as other information are parts of the configuration of the high-speed communication system, which are either known a priori or may be calculated from a set of GPS satellite transmitters similar to transmitter 114.
  • the position location information based on transmitter 114 specifies the user antenna 103 and satellite transceiver 112A location, it will be appreciated that such information cannot identify or determine the orientation of antenna 103.
  • user transceiver 104 determines relative antenna 103 location information, U.
  • Transmitter 114 location information S is broadcasted through the ephemeris navigation message of transmitter 114.
  • ECEF earth-centered, earth-fixed
  • Antenna directing system 125 may further include a direction finding mechanism to track, and accurately point to, position location transmitter 114.
  • Direction finding mechanism comprises an array of calibration antenna element pairs 102D, 102E, mounted on user antenna 103, and a beam-forming network 107, both used in conjunction with alignment mechanism 105.
  • calibration antenna element pairs 102D, 102E may be configured as circularly polarized micro-strip patch antennas or other antenna elements suitable for such purposes.
  • calibration antenna element pairs 102D, 102E may be mounted on diametrically opposite corners of antenna 103, having a boresight axis for the array formed by these elements coincident with the boresight of antenna 103.
  • antenna element pairs 102D, 102E may be used to generate two orthogonal radiation beam patterns. These patterns may then be processed to generate the sum and difference between the patterns, as indicated in FIG. ID, to assist in identifying the elevation and azimuthal directions rendering the strongest signals from position location transmitter 114. Alignment mechanism 105 is then used to direct user antenna 103 to accurately point to position location transmitter 114, based on direction rendering the strongest signals.
  • Beam-forming network 107 is configured to process the transmit and receive beam patterns conveying signals of interest, including the two orthogonal radiation beam patterns generated by array of calibration antenna element pairs 102D, 102E.
  • Beam- forming network 104 may comprise transform matrices and gain/phase adjusting elements as well as associated circuitry to achieve the desired beam patterns.
  • Such circuitry may include, for example, combiners, splitters, and switching mechanisms, all of which have been omitted for the sake of brevity.
  • system 125 exploits the position location information between antenna 103 and transmitter 114 to generate a reference vector and a corresponding vector reference space.
  • the reference vector and vector reference space will be used as a frame of reference, allowing the deduction of orientation information (e.g., elevation and azimuthal direction information) to properly orient user antenna 103.
  • orientation information e.g., elevation and azimuthal direction information
  • the properly oriented user antenna 103 may then be automatically aligned to point to the satellite antenna 110A, by virtue of the satellite transceiver's 112A position location information.
  • FIG. 1C illustrates an automatic antenna directing system 150 operative with a high-speed, terrestrially-based data communication network, in accordance with an embodiment of the present invention.
  • Terrestrially-based data communication network may comprise, for example, a wireless data network, including, but not limited to, microwave line-of-sight networks and cellular networks.
  • a wireless data network including, but not limited to, microwave line-of-sight networks and cellular networks.
  • some of the components in the terrestrially-based antenna directing system 150 are similar to the components identified in satellite-based antenna directing system 125 and are, therefore, denoted by like reference numerals. In the interest of brevity, some of these similar components will not be described further, it being understood that the lack of such description does not sacrifice any aspect of the present embodiment.
  • Antenna directing system 150 employs a user antenna 103, which communicates, via terrestrial antenna HOB, with a terrestrial communications transceiver 112B to affect the transfer of high-speed data.
  • Terrestrial transceiver 112B and terrestrial antenna HOB may comprise, for example, a base station transceiver system and associated base station antenna arrangement.
  • user antenna 103 radiates a narrow transmit beam pattern for the transmission of data to terrestrial antenna HOB and collects a receive beam pattern from terrestrial antenna HOB for the reception of data.
  • System 150 also employs a position location receiver 106, coupled to user antenna 103, which may be configured to receive position location information from a position location transmitter 114.
  • the location information of user antenna 103, transmitter 114, and terrestrial antenna HOB may be stored in a position location database.
  • position location information cannot identify or determine the orientation of user antenna 103.
  • User transceiver 104 determines antenna 103 location information, U, and receives transmitter 114 location information, S.
  • FIG. 2A is a functional flow diagram depicting automatic antenna directing process 200, constructed and operative in accordance with an embodiment of the present invention.
  • process 200 operates to determine the necessary orientation information (e.g., elevation and azimuthal direction information) to properly orient user antenna 103.
  • the properly oriented user antenna 103 may then be automatically aligned to point to the satellite or terrestrial antenna HOA, HOB by using the satellite transceiver 112A position location information or the terrestrial transceiver 112B position location information.
  • process 200 initiates the acquisition of position location information with respect to user antenna 103, position location transmitter 114, and satellite transceiver antenna HOA or terrestrial transceiver antenna HOB.
  • position location transmitter 114 employs a plurality of position location transmitters that communicate timing information, user antenna 103 position location, network transceiver antenna HOA, HOB position location, and ephemeris data identifying position location of the transmitters in view. Accordingly, process 200 acquires the relevant information communicated by the various position location transmitters.
  • process 200 Upon receiving the relevant information communicated by the various position location transmitters, in block B212, process 200 selects at least one position location transmitter 114, from the plurality of transmitters, having acceptable signal conditions and/or signal levels. Such acceptable signal conditions may include, for example, a transmitter signal having signal-to-noise ratio (SNR) that meets a predetermined threshold. By doing so, process 200 ensures that it operates with only the strongest transmitter position location signals.
  • SNR signal-to-noise ratio
  • process 200 utilizes the capabilities of the direction finding mechanism to precisely point user antenna 103 to the at least one position location transmitter 114.
  • the precise pointing of user antenna 103 facilitates the establishment of vector reference space that will subsequently be used to accurately calibrate the orientation of user antenna 103.
  • process 200 implements the direction finding capabilities by initiating the formation and radiation of two orthogonal beam patterns from the array of calibration antenna element pairs 102D, 102E, as indicated in block B214A.
  • One beam pattern is in the elevation plane while the other is in the azimuthal plane.
  • Calibration antenna element pairs 102D, 102E may be mounted on diametrically opposite corners of antenna 103, having a boresight axis for the array formed by these elements coincident with the boresight of antenna 103.
  • the true north vector n for calibration antenna element pairs 102D, 102E is the same as that of antenna 103.
  • process 200 initiates the formation of the sum and difference of the two orthogonal beam patterns along each of the elevation and azimuthal planes by beam forming network 107.
  • Typical sum and difference patterns in the azimuthal plane are plotted in FIG. IB, as a function of gain and azimuthal angle ⁇ .
  • Plots for the elevation plane are similarly configured.
  • One notable characteristic of the difference patterns is the steep null between the lobes, which represent the maximum gain of the beam patterns.
  • process 200 adjusts user antenna 103 relative to the steep null of the difference pattern for the elevation and azimuthal planes. Specifically, for both the elevation and azimuthal planes, user transceiver mechanism 104 tracks the gain of the difference pattern.
  • mechanism 104 Upon detecting the steep null within the respective difference patterns, mechanism 104 communicates the elevation angle ⁇ and azimuthal angle ⁇ information associated with the null to processing mechanism 108A. Processing mechanism 108A then generates a first set of control signals based on the elevation and azimuthal angle ⁇ , ⁇ information to drive alignment mechanism 105 along the elevation and azimuthal planes in order to automatically align antenna 103 along the direction of optimal gain. In this manner, process 200 is able to exploit the direction finding capabilities to automatically and accurately direct user antenna 103 to point to the at least one position location transmitter 114.
  • process 200 may then establish a precise and reliable vector reference space.
  • process 200 In response to identifying position vectors U, S, process 200 establishes a reference vector R, which points from the user antenna 103 location, U, to the transmitter 114 location, S. With position vectors U, S and reference vector R, process 200 may then establish a vector reference space, which serves as a frame of reference from which orientation information may be deduced.
  • Vector reference space also comprises unit vector n, which points north from user location U, and unit vector e, which points east from U. Note that the three unit vectors u, n, and e are pair-wise orthogonal.
  • Equations (2) and (3) establish vector reference space comprising unit vector n, which points true north from user location U, and unit vector e, which points east. Note that Equations (2) and (3) are not valid when vectors u and z are parallel, i.e. when the user is located at either the North or South Pole
  • process 200 is capable of deducing the orientation information necessary to calibrate and properly orient user antenna 103.
  • the orientation information includes elevation direction and azimuthal direction components.
  • process 200 in block B218, determines the elevation directional information necessary for orienting user antenna 103 in the proper elevation direction. This is achieved by calculating the offset elevation angle ⁇ , which defines the necessary angular adjustment of user antenna 103 along vector u. Offset elevation angle ⁇ is related to the projection of vector r onto u and may be calculated as follows:
  • ⁇ sin "1 (r • u) (4) where r • u is the scalar product between vectors r and u.
  • ⁇ cos- 1 [ (n . p)/
  • sign ( ⁇ ) sign (e » p) (7)
  • n • p and e • p are the scalar products of n and p and e and p, respectively, and
  • process 200 Upon calculating the elevation and azimuthal direction information, process 200 achieves the orientation information necessary to properly calibrate and orient user antenna 103.
  • reference vector r the vector reference space, offset elevation angle ⁇ , and offset azimuthal angle ⁇
  • user antenna 103 may be adjusted and corrected to achieve proper orientation. Accordingly, in an exemplary embodiment, this may be achieved by having processing mechanism 108A generate a second set of control signals, based on offset elevation angle ⁇ and offset azimuthal angle ⁇ , to drive alignment mechanism 105 along the proper directions to orient user antenna 103.
  • offset angle ⁇ measured between the projection of vector v and the projection of u on the plane P r , where P r is a plane perpendicular to vector r.
  • This offset angle ⁇ must be additionally corrected for in all subsequent antenna orientation operations. Said corrections may be carried out by processing mechanism 108A, by way of using appropriate coordinate transformations when converting the desired elevation and azimuthal movements to signals driving alignment mechanism 105. [0053] As mentioned above, it may be necessary in some cases, i.e. when the initial parallel orientation of vectors u and v cannot be ensured, to determine offset angle ⁇ .
  • This may be done, for example, by repeating the operation of block B214 to align user antenna 103 to a second position location transmitter 114, or to the same position location transmitter as before but after it is moved to a different location, and compute ⁇ from the offset elevation angles ⁇ and offset azimuthal angles ⁇ , resulting from the two block B214 operations.
  • a more efficient method of determining ⁇ is when the alignment to the second position location transmitter 114 is aided by utilizing information obtained during alignment to the first position location transmitter.
  • an appropriate second position location transmitter 114 is chosen, whose location is such that the vector pointing to it from user location U is not parallel to the vector pointing to the first position location transmitter.
  • the position location information of the second position location transmitter 114 is translated into corresponding target elevation and azimuthal direction information valid at user location U.
  • Process 200 then aligns antenna 103 along the target elevation and azimuthal direction information in an attempt to point it to the chosen second position location transmitter 114. If the second position location transmitter is found precisely at that direction, then ⁇ is zero and no further correction is needed.
  • the second position location transmitter can be searched for by changing the azimuthal angle that is measured in plane P r , where P r is a plane perpendicular to vector r, while keeping the elevation that is measured relative to P r constant.
  • ⁇ will be readily determined as the azimuthal adjustment that took place in plane P r , relative to the initial position. Note that since offset angle ⁇ is determined as an azimuthal difference in plane P r , appointing a reference 'zero' azimuthal direction in plane P r is not required. Also note that the best geometry for determining ⁇ is when the angle seen from user location U between the first and second position location transmitters is approximately 90°.
  • process 200 may then align antenna 103 to point to the desired network communication transceiver, i.e., satellite communication antenna HOA or terrestrial communication antenna HOB.
  • desired network communication transceiver i.e., satellite communication antenna HOA or terrestrial communication antenna HOB.
  • process 200 uses the network transceiver antenna 110A HOB position location information, which may be translated into corresponding target elevation and azimuthal direction information.
  • Process 200 then aligns antenna 103 along the target elevation and azimuthal direction information to point to the desired network communication transceiver. In an exemplary embodiment, this may be achieved by having processor mechanism 108A generate a third set of control signals based on the target elevation and azimuthal direction information to drive alignment mechanism 105 to automatically adjust and align antenna 103 along the desired directions.
  • the separate alignments based on the second and third set of control signals may be done in a single step based on a single set of control signals. This single set is obtained with subtracting the control signals in the second set from the control signals in the third set.

Abstract

A system and method for automatically directing a communication antenna to point to a desired wireless communication transceiver, is presented herein. The system includes a position location receiver, which receives signals indicating the position location information of the antenna and a position location transmitter and a processing mechanism, which determines calibration information of the antenna. The calibration information is achieved by first establishing a reference vector between the location of the antenna and position location transmitter and establishing a vector reference space and then calculate the necessary elevation and azimuthal components, within the vector reference space, to identify the proper calibration of the antenna. Once the calibration information has been determined, an alignment mechanism automatically orients the antenna. The alignment mechanism then automatically directs the oriented antenna to point to the wireless transceiver, based on the directional location information of the wireless transceiver.

Description

SYSTEM AND METHOD FOR AUTOMATIC DETERMINATION OF AZIMUTHAL AND ELEVATION DIRECTION OF DIRECTIONAL
ANTENNAS AND CALIBRATION THEREOF
BACKGROUND OF THE INVENTION
Reservation of Copyright
[0001] The disclosure of this patent document contains material which is 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 U.S. Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
Field of the Invention
[0002] The present invention relates generally to the field of wireless communications and, in particular, to an automatic antenna directing system capable of accurately pointing a wireless communication directional antenna at a desired transceiver.
Description of Background Information
[0003] Recent advances in computer and cellular technologies, as well as the unprecedented growth of Internet-related applications, have resulted in placing great demands on conventional communication infrastructures to convey information at high transmission rates with increased reliability. For example, conventional infrastructures were based, at least in part, on statistical telephonic usage patterns. As users progressively spend more time on the Internet and tie up communication lines for longer periods of time, traditional usage patterns are no longer dependable. In many cases, such changes in usage patterns render conventional infrastructures inadequate.
[0004] In an effort to meet the demand for high transmission rates and provide users with high-speed Internet access, various wireline and wireless solutions have evolved. Wireline solutions, which include cable network services and Digital Subscriber Line (DSL) services, offer relief to subscribers having access to such services. Because of the relatively high capital expenditures and labor costs associated with providing connectivity and access to new regions, these services are far from ubiquitous.
[0005] On the other hand, wireless solutions are more cost effective and may service a wider range of subscribers. These wireless solutions are based on high-speed wireless data communication systems that employ either satellite-based data networks, such as, for example, DirecPC and StarBand services, or terrestrially-based data networks, such as cellular data networks.
[0006] Typically, these high-speed wireless data communication systems are power limited hence contemplate the use of a high-gain, narrow beam, highly-directional fixed antenna coupled to a user terminal to deliver information to a subscriber. As such, these fixed user antennas generally manifest stringent alignment requirements. That is, to ensure adequate communication capabilities, the user transmit or receive antennas need to accurately point in the direction of their counterpart antennas for both transmit and receive operations. For example, in high-speed satellite-based data communication systems link budgets have small margins, hence user antennas need to point to a satellite along specific elevation and azimuthal directions in order to maximize the gain of the received beam pattern and, thus, ensure optimal data transmission. Similarly, for high-speed terrestrially- based data communication systems, user antennas need to be aligned along specific elevation and azimuthal directions to point to the radiation center of a cellular antenna arrangement to ensure maximum possible signal-to-noise ratio. It will be appreciated that, although the specific location of both the user antenna and satellite antenna or cellular antenna may be known, such information does little to identify the exact orientation of the user antenna.
[0007] With this said, it is to be noted that most fixed antennas are susceptible to misalignment. Various factors, such as, poor initial installation, atmospheric conditions (e.g., wind), and antenna site construction may all contribute to antenna misalignment. Consequently, the misalignment of highly-directional user antennas may have a deleterious effect on the performance of high-speed wireless data communication systems. [0008] Traditionally, the calibration and corrective re-alignment of fixed antennas require the dispatch of a technician to physically adjust the antenna in the direction containing the strongest signal. Such a process is not cost effective and fraught with inaccuracies as technicians often employ a trial-and-error approach to correct misalignments. Moreover, the process is time and task intensive, often requiring several hours of system down time before the misalignment can be corrected. This goes against the normal plug-and-go approach of most of today's applications.
SUMMARY OF THE INVENTION
[0009] Systems and methods consistent with the principles of the present invention, as embodied and broadly described herein, provide for an automatic antenna directing system capable of accurately pointing a wireless communication antenna at a desired transceiver.
[0010] In one embodiment, the system includes a position location receiver, which receives signals indicating position location information of the antenna and a position location transmitter. A processing mechanism coupled to the position location receiver determines calibration information of the antenna based on the location information of the antenna and the position location transmitter. An alignment mechanism coupled to the processing mechanism and the antenna, automatically orients the antenna, based on the calibration information, and automatically directs the oriented antenna to point to the wireless transceiver, based on the directional location information of the wireless transceiver.
[0011] Additional aspects of the present invention include determining the calibration information by first accurately pointing to the position location transmitter via a direction finding mechanism and then establishing a vector reference space. The necessary elevation and azimuthal components, within the vector reference space, are then calculated to identify the proper calibration of the antenna. Once the calibration information has been determined, an alignment mechanism automatically orients the antenna and, based on the directional location information of the wireless transceiver, alignment mechanism automatically directs the oriented antenna to point to the wireless transceiver. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The above noted features and advantages of the present invention are further described in the detailed description which follows, with reference to the drawings, wherein like reference numerals represent similar parts of the present invention throughout the several views and wherein:
[0013] FIG. 1A illustrates a functional block diagram of an automatic antenna directing system, constructed and operative in accordance with an embodiment of the present invention;
[0014] FIG. IB illustrates a functional block diagram of an automatic antenna directing system in a satellite network application, constructed and operative in accordance with another embodiment of the present invention;
[0015] FIG. 1C illustrates a functional block diagram of an automatic antenna directing system in a terrestrial network application, constructed and operative in accordance with another embodiment of the present invention;
[0016] FIG. ID illustrates beam patterns as functions of gain and azimuthal angles, in accordance with another embodiment of the present invention;
[0017] FIG. 2A depicts a functional flow chart diagram of an automatic directing process, constructed and operative in accordance with an embodiment of the present invention; and
[0018] FIG. 2B depicts a spatial vector reference diagram in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0019] The following detailed description of the present invention refers to the accompanying drawings that illustrate exemplary embodiments consistent with this invention. Other embodiments are possible and modifications may be made to the embodiments without departing from the spirit and scope of the invention. Therefore, the following detailed description is not meant to limit the invention. Rather the scope of the invention is defined by the appended claims. [0020] The embodiments described below may, instead, be implemented in many different embodiments of software, firmware, and hardware in the entities illustrated in the figures. The actual software code or specialized control hardware used to implement the present invention is not limiting of the present invention. Thus, the operation and behavior of the present invention will be described with the understanding that modification and variations of the embodiments are possible, given the level of detail present herein. [0021] As will be described in greater detail below, a system for automatically directing a user antenna that accurately points to a desired communication transceiver may be employed to ensure adequate performance of high-speed data communication networks. In one embodiment, the system exploits the position location information between a position location receiver and a position location transmitter to generate a reference vector and a corresponding vector reference space. Because the position location information only contains location information and cannot render orientation information of the* user antenna, the reference vector and vector reference space are used as a frame of reference to facilitate the deduction of orientation information (e.g., elevation and azimuthal direction information). This orientation information is then used to calibrate and properly orient the user antenna. Once the user antenna has been oriented, the user antenna may then be aligned to point to the desired communication transceiver based on the position location information of the transceiver or other methods. An antenna alignment mechanism then automatically adjusts the user antenna to point to the transceiver based on the user and the transceiver location information.
[0022] FIG. 1A illustrates an automatic antenna directing system 100, constructed and operative in accordance with an embodiment of the present invention. For purposes of illustration, many of the well-known features of wireless communications, such as, for example, filters, duplexers, amplifiers, and up/down converters that are ancillary to the present invention have been omitted.
[0023] Antenna directing system 100 may be used in conjunction with the high-speed wireless data communication services. As will be described in greater detail below, the high-speed wireless data communication services may be provided by either a satellite- based or terrestrially-based data communication network. Regardless of the network platform, system 100 employs a user terminal 108, which is coupled to a user communication antenna 102A. User antenna 102A communicates with a network communication transceiver mechanism 112 via a network communication antenna 110. User terminal 108 may include a processing mechanism 108A configured to execute program instructions residing in system memories. Such program instructions may control and/or manage various aspects of system 100, including, but not limited to, the processing of position location information, the determination of elevation and azimuthal direction information, and the generation of antenna orientation control signals. [0024] System 100 further comprises a user communication transceiver mechanism 104 coupled to both user terminal 108 and user communication antenna 102A. Along the transmit path, user transceiver mechanism 104 is configured to modulate and up-convert the baseband data into a form suitable for subsequent radiation by user communication antenna 102A. On the receive path, user transceiver mechanism 104 is configured to demodulate and down-convert the signals received by user communication antenna 102A into baseband data.
[0025] User antenna 102A may also comprise alignment mechanism 105, capable of aligning antenna 102A along the elevation and azimuthal directions. Alignment mechanism 105 may comprise motorized components and associated circuitry to align antenna 102A along the proper directions once the elevation and azimuthal directional information have been resolved. To this end, alignment mechanism 105 may receive control signals from processing mechanism 108A to drive the motorized components and align antenna 102A along the proper directions.
[0026] System 100 may further comprise a position location receiver 106, such as, for example, a Global Positioning System (GPS) receiver or similar navigation/position location receiver, and an associated position location antenna 102B. Position location receiver 106 is configured to process and provide antenna 102B location information from at least one geostationary satellite capable of rendering position location services. Such information may be based on GPS or similar navigation/position location systems, which employ a plurality of position location transmitters (e.g., 3 or more) to yield accurate position location information. Consistent with navigation/position location systems, these transmitters may be configured as orbiting satellites (e.g., GPS satellites). [0027] As indicated in FIG. 1A, user communication antenna 102A may also serve as position location antenna 102B or may be integrated with position location antenna 102B to form integrated antenna 103 that functions as both a communication and position location antenna. To this end, alignment mechanism 105 may be used in conjunction with the position location functionality to provide directional finding capabilities for tracking the position location transmitters.
[0028] FIG. IB illustrates an automatic antenna directing system 125 operative with a high-speed, satellite-based data communication network, in accordance with an embodiment of the present invention. As indicated in FIG. IB, antenna directing system 125 employs an integrated user antenna 103, which communicates, via a satellite network antenna 110A, with a satellite network transceiver 112A (e.g., transponder) to effect the transmission of the high-speed data. As such, user antenna 103 radiates a narrow transmit beam pattern for the transmission of data to satellite antenna 110A and collects a receive beam pattern from satellite antenna 110A for the reception of data. Although user antenna 103 is depicted as a microwave dish antenna, it will be appreciated that other antenna configurations may be employed.
[0029] Antenna directing system 125 further comprises a position location receiver 106, coupled to user antenna 103. As such, user antenna 103 may be configured to also receive position location information from a position location transmitter 114. As noted above, such information may be based on GPS or similar navigation/position location systems, employing a plurality of position location transmitters (e.g., 3 or more), which may configured as orbiting satellites (e.g., GPS satellites).
[0030] Position location transmitter 114 may be configured to furnish, on a predetermined basis, data detailing timing information and ephemeris data indicating the position location of transmitter 114. The position location of satellite transceiver 112A, as well as other information are parts of the configuration of the high-speed communication system, which are either known a priori or may be calculated from a set of GPS satellite transmitters similar to transmitter 114. Although the position location information based on transmitter 114 specifies the user antenna 103 and satellite transceiver 112A location, it will be appreciated that such information cannot identify or determine the orientation of antenna 103. To this end, user transceiver 104 determines relative antenna 103 location information, U. Transmitter 114 location information, S is broadcasted through the ephemeris navigation message of transmitter 114. For an instant in time, the antenna 103 and transmitter 114 location information may be defined as position vectors U = {ux, uy, uz) and S = {sx, sy, sz), respectively, in accordance with the well-known earth-centered, earth-fixed (ECEF) WGS-84 frame reference standard.
[0031] Antenna directing system 125 may further include a direction finding mechanism to track, and accurately point to, position location transmitter 114. Direction finding mechanism comprises an array of calibration antenna element pairs 102D, 102E, mounted on user antenna 103, and a beam-forming network 107, both used in conjunction with alignment mechanism 105. As will be described in greater detail below, calibration antenna element pairs 102D, 102E may be configured as circularly polarized micro-strip patch antennas or other antenna elements suitable for such purposes. Moreover, calibration antenna element pairs 102D, 102E may be mounted on diametrically opposite corners of antenna 103, having a boresight axis for the array formed by these elements coincident with the boresight of antenna 103. As such, antenna element pairs 102D, 102E may be used to generate two orthogonal radiation beam patterns. These patterns may then be processed to generate the sum and difference between the patterns, as indicated in FIG. ID, to assist in identifying the elevation and azimuthal directions rendering the strongest signals from position location transmitter 114. Alignment mechanism 105 is then used to direct user antenna 103 to accurately point to position location transmitter 114, based on direction rendering the strongest signals.
[0032] Beam-forming network 107 is configured to process the transmit and receive beam patterns conveying signals of interest, including the two orthogonal radiation beam patterns generated by array of calibration antenna element pairs 102D, 102E. Beam- forming network 104 may comprise transform matrices and gain/phase adjusting elements as well as associated circuitry to achieve the desired beam patterns. Such circuitry may include, for example, combiners, splitters, and switching mechanisms, all of which have been omitted for the sake of brevity.
[0033] As will be described in greater detail below, system 125 exploits the position location information between antenna 103 and transmitter 114 to generate a reference vector and a corresponding vector reference space. The reference vector and vector reference space will be used as a frame of reference, allowing the deduction of orientation information (e.g., elevation and azimuthal direction information) to properly orient user antenna 103. The properly oriented user antenna 103 may then be automatically aligned to point to the satellite antenna 110A, by virtue of the satellite transceiver's 112A position location information.
[0034] FIG. 1C illustrates an automatic antenna directing system 150 operative with a high-speed, terrestrially-based data communication network, in accordance with an embodiment of the present invention. Terrestrially-based data communication network may comprise, for example, a wireless data network, including, but not limited to, microwave line-of-sight networks and cellular networks. It is to be noted that some of the components in the terrestrially-based antenna directing system 150 are similar to the components identified in satellite-based antenna directing system 125 and are, therefore, denoted by like reference numerals. In the interest of brevity, some of these similar components will not be described further, it being understood that the lack of such description does not sacrifice any aspect of the present embodiment. [0035] Antenna directing system 150 employs a user antenna 103, which communicates, via terrestrial antenna HOB, with a terrestrial communications transceiver 112B to affect the transfer of high-speed data. Terrestrial transceiver 112B and terrestrial antenna HOB may comprise, for example, a base station transceiver system and associated base station antenna arrangement. As such, user antenna 103 radiates a narrow transmit beam pattern for the transmission of data to terrestrial antenna HOB and collects a receive beam pattern from terrestrial antenna HOB for the reception of data.
[0036] System 150 also employs a position location receiver 106, coupled to user antenna 103, which may be configured to receive position location information from a position location transmitter 114. The location information of user antenna 103, transmitter 114, and terrestrial antenna HOB may be stored in a position location database. As noted above, with respect to antenna directing system 125, position location information cannot identify or determine the orientation of user antenna 103. User transceiver 104 determines antenna 103 location information, U, and receives transmitter 114 location information, S. For an instant in time, the antenna 103 and transmitter 114 location information may be defined as position vectors U = {ux, uy, uz) and S = {sx, sy, sz), respectively.
[0037] As indicated above with respect to system 125 and described in greater detail below, system 150 exploits the position location information between user antenna 103 and transmitter 114 to generate a reference vector and a corresponding vector reference space. The reference vector and vector reference space will be used as a frame of reference, allowing the deduction of orientation information (e.g., elevation and azimuthal direction information) to properly orient user antenna 103. The properly oriented user antenna 103 may then be automatically aligned to point to the terrestrial antenna HOB, by using the terrestrial transceiver's 112B position location information. [0038] FIG. 2A is a functional flow diagram depicting automatic antenna directing process 200, constructed and operative in accordance with an embodiment of the present invention. In conjunction with the system embodiments presented above, process 200 operates to determine the necessary orientation information (e.g., elevation and azimuthal direction information) to properly orient user antenna 103. The properly oriented user antenna 103 may then be automatically aligned to point to the satellite or terrestrial antenna HOA, HOB by using the satellite transceiver 112A position location information or the terrestrial transceiver 112B position location information.
[0039] As indicated in block B210, process 200 initiates the acquisition of position location information with respect to user antenna 103, position location transmitter 114, and satellite transceiver antenna HOA or terrestrial transceiver antenna HOB. As noted above, well- known navigation systems, such as, for example, GPS, employ a plurality of position location transmitters that communicate timing information, user antenna 103 position location, network transceiver antenna HOA, HOB position location, and ephemeris data identifying position location of the transmitters in view. Accordingly, process 200 acquires the relevant information communicated by the various position location transmitters. [0040] Upon receiving the relevant information communicated by the various position location transmitters, in block B212, process 200 selects at least one position location transmitter 114, from the plurality of transmitters, having acceptable signal conditions and/or signal levels. Such acceptable signal conditions may include, for example, a transmitter signal having signal-to-noise ratio (SNR) that meets a predetermined threshold. By doing so, process 200 ensures that it operates with only the strongest transmitter position location signals.
[0041] In block B214, process 200 utilizes the capabilities of the direction finding mechanism to precisely point user antenna 103 to the at least one position location transmitter 114. The precise pointing of user antenna 103 facilitates the establishment of vector reference space that will subsequently be used to accurately calibrate the orientation of user antenna 103.
[0042] In an exemplary implementation, process 200 implements the direction finding capabilities by initiating the formation and radiation of two orthogonal beam patterns from the array of calibration antenna element pairs 102D, 102E, as indicated in block B214A. One beam pattern is in the elevation plane while the other is in the azimuthal plane. Calibration antenna element pairs 102D, 102E may be mounted on diametrically opposite corners of antenna 103, having a boresight axis for the array formed by these elements coincident with the boresight of antenna 103. As such, the true north vector n for calibration antenna element pairs 102D, 102E is the same as that of antenna 103. [0043] In block B214B, process 200 initiates the formation of the sum and difference of the two orthogonal beam patterns along each of the elevation and azimuthal planes by beam forming network 107. Typical sum and difference patterns in the azimuthal plane are plotted in FIG. IB, as a function of gain and azimuthal angle Φ. Plots for the elevation plane are similarly configured. One notable characteristic of the difference patterns is the steep null between the lobes, which represent the maximum gain of the beam patterns. [0044] In block B214C, process 200 adjusts user antenna 103 relative to the steep null of the difference pattern for the elevation and azimuthal planes. Specifically, for both the elevation and azimuthal planes, user transceiver mechanism 104 tracks the gain of the difference pattern. Upon detecting the steep null within the respective difference patterns, mechanism 104 communicates the elevation angle θ and azimuthal angle Φ information associated with the null to processing mechanism 108A. Processing mechanism 108A then generates a first set of control signals based on the elevation and azimuthal angle θ, Φ information to drive alignment mechanism 105 along the elevation and azimuthal planes in order to automatically align antenna 103 along the direction of optimal gain. In this manner, process 200 is able to exploit the direction finding capabilities to automatically and accurately direct user antenna 103 to point to the at least one position location transmitter 114.
[0045] Upon accurately pointing user antenna 103 to the at least one position location transmitter 114, process 200, in block B216, may then establish a precise and reliable vector reference space. By way of example, consider the attributes of the satellite-based data communication network depicted in FIG. 2C. In this illustrative example, the position location of user antenna 103 and the at least one position location transmitter 114 may be defined, relative to the earth's center, as position vectors U = {ux, uy, uz) and S = {sx, sy, sz), respectively. In response to identifying position vectors U, S, process 200 establishes a reference vector R, which points from the user antenna 103 location, U, to the transmitter 114 location, S. With position vectors U, S and reference vector R, process 200 may then establish a vector reference space, which serves as a frame of reference from which orientation information may be deduced.
[0046] The vector reference space comprises unit vector u = U/|U|, where |U| denotes the magnitude of vector U. Vector reference space also comprises unit vector n, which points north from user location U, and unit vector e, which points east from U. Note that the three unit vectors u, n, and e are pair-wise orthogonal. The unit vector r pointing from U to S is defined as: r = (S-U)/|S-U| (1) where |S-U| denotes magnitude of S-U. Further, vector reference space also includes unit vector z , which is defined as pointing north from the center of the earth, z = {zx= , zy= , Zz=l), i.e., parallel to the ECEF Z-axis.
[0047] It will be appreciated that the unit vector e pointing to the east from the user location U on the surface of the earth is given by: e = (z x U)/|z x U| (2) where z x U denotes cross product of z and U. Similarly, it can be shown that the unit vector n pointing north from the user location U on the surface of the earth is given by: n = U x e/|U| (3)
[0048] Equations (2) and (3) establish vector reference space comprising unit vector n, which points true north from user location U, and unit vector e, which points east. Note that Equations (2) and (3) are not valid when vectors u and z are parallel, i.e. when the user is located at either the North or South Pole
[0049] Based on unit reference vector r and the vector reference space, process 200 is capable of deducing the orientation information necessary to calibrate and properly orient user antenna 103. The orientation information includes elevation direction and azimuthal direction components. In particular, process 200, in block B218, determines the elevation directional information necessary for orienting user antenna 103 in the proper elevation direction. This is achieved by calculating the offset elevation angle Δθ, which defines the necessary angular adjustment of user antenna 103 along vector u. Offset elevation angle Δθ is related to the projection of vector r onto u and may be calculated as follows:
Δθ = sin"1 (r • u) (4) where r • u is the scalar product between vectors r and u.
[0050] In block B216, process 200 also determines the azimuthal directional information necessary for orienting user antenna 103 in the proper azimuthal direction. Specifically, process 200 first calculates the projection p of vector r onto the horizontal plane going through point U. Since the horizontal plane going through point U is perpendicular to vector u, then projection p can be calculated as: p = r - u (r • u) (5) where u (r • u) is the product of u with the resulting scalar product of (r • u). Based on projection p, process 200 determines the azimuthal direction information by calculating the offset azimuthal angle ΔΦ, which defines the necessary angular adjustment of user antenna 103 along the true north vector n. As such, offset azimuthal angle ΔΦ may be calculated as follows:
ΔΦ = cos-1 [ (n . p)/ | p | ] (6) sign (ΔΦ) = sign (e » p) (7) where n • p and e • p are the scalar products of n and p and e and p, respectively, and | p | denotes the magnitude of p.
[0051] Upon calculating the elevation and azimuthal direction information, process 200 achieves the orientation information necessary to properly calibrate and orient user antenna 103. In other words, by virtue of reference vector r, the vector reference space, offset elevation angle Δθ, and offset azimuthal angle ΔΦ, user antenna 103 may be adjusted and corrected to achieve proper orientation. Accordingly, in an exemplary embodiment, this may be achieved by having processing mechanism 108A generate a second set of control signals, based on offset elevation angle Δθ and offset azimuthal angle ΔΦ, to drive alignment mechanism 105 along the proper directions to orient user antenna 103.
[0052] The corrections based on offset elevation angle Δθ and offset azimuthal angle ΔΦ will achieve the desired antenna orientation, if those corrections are done along the proper directions. This assumes that the physical azimuthal plane Pa of alignment mechanism
105, i.e. the plane in which the physical antenna azimuthal adjustment takes place, is parallel to the true horizontal plane at user location U. This condition is equivalent to vector u being parallel to vector v, where v is a vector perpendicular to plane Pa. Even in the case when vectors u and v are not parallel, but when u, v and vector r all lie in the same plane, the corrections based on offset elevation angle Δθ and offset azimuthal angle ΔΦ, explained above, will achieve the desired orientation of user antenna 103. On the other hand, if vector v doesn't lie in the plane spanned by vectors u and r, then offset angle Δα measured between the projection of vector v and the projection of u on the plane Pr, where Pr is a plane perpendicular to vector r. This offset angle Δα must be additionally corrected for in all subsequent antenna orientation operations. Said corrections may be carried out by processing mechanism 108A, by way of using appropriate coordinate transformations when converting the desired elevation and azimuthal movements to signals driving alignment mechanism 105. [0053] As mentioned above, it may be necessary in some cases, i.e. when the initial parallel orientation of vectors u and v cannot be ensured, to determine offset angle Δα. This may be done, for example, by repeating the operation of block B214 to align user antenna 103 to a second position location transmitter 114, or to the same position location transmitter as before but after it is moved to a different location, and compute Δα from the offset elevation angles Δθ and offset azimuthal angles ΔΦ, resulting from the two block B214 operations.
[0054] A more efficient method of determining Δα is when the alignment to the second position location transmitter 114 is aided by utilizing information obtained during alignment to the first position location transmitter. In a preferred embodiment, first, an appropriate second position location transmitter 114 is chosen, whose location is such that the vector pointing to it from user location U is not parallel to the vector pointing to the first position location transmitter. The position location information of the second position location transmitter 114 is translated into corresponding target elevation and azimuthal direction information valid at user location U. Process 200 then aligns antenna 103 along the target elevation and azimuthal direction information in an attempt to point it to the chosen second position location transmitter 114. If the second position location transmitter is found precisely at that direction, then Δα is zero and no further correction is needed. Otherwise, the second position location transmitter can be searched for by changing the azimuthal angle that is measured in plane Pr, where Pr is a plane perpendicular to vector r, while keeping the elevation that is measured relative to Pr constant. Once user antenna 103 is precisely aligned by this process to second position location transmitter 114, Δα will be readily determined as the azimuthal adjustment that took place in plane Pr, relative to the initial position. Note that since offset angle Δα is determined as an azimuthal difference in plane Pr, appointing a reference 'zero' azimuthal direction in plane Pr is not required. Also note that the best geometry for determining Δα is when the angle seen from user location U between the first and second position location transmitters is approximately 90°.
[0055] Finally, once user antenna 103 has been properly oriented, process 200 may then align antenna 103 to point to the desired network communication transceiver, i.e., satellite communication antenna HOA or terrestrial communication antenna HOB. Specifically, in block B220, process 200 uses the network transceiver antenna 110A HOB position location information, which may be translated into corresponding target elevation and azimuthal direction information. Process 200 then aligns antenna 103 along the target elevation and azimuthal direction information to point to the desired network communication transceiver. In an exemplary embodiment, this may be achieved by having processor mechanism 108A generate a third set of control signals based on the target elevation and azimuthal direction information to drive alignment mechanism 105 to automatically adjust and align antenna 103 along the desired directions. [0056] The separate alignments based on the second and third set of control signals, both explained above, may be done in a single step based on a single set of control signals. This single set is obtained with subtracting the control signals in the second set from the control signals in the third set.
[0057] The foregoing description of the embodiments of the present invention provides illustration and description, but is not intended to be exhaustive or to limit the invention to the precise form disclosed. Modifications and variations are possible consistent with the above teachings or may be acquired from practice of the invention. For example, the various features of the invention, which are described in the contexts of separate embodiments for the purposes of clarity, may also be combined in a single embodiment. Conversely, the various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub- combination. Accordingly, it will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention is defined only by the attached claims and their equivalents.
WHAT IS CLAIMED:

Claims

1. A system for automatically directing a communication antenna to point to a desired wireless communication transceiver, comprising: a position location receiver configured to receive signals indicating position location information of said antenna and at least one position location transmitter; a processing mechanism operatively coupled to said position location receiver and configured to determine calibration information of said antenna based on said location information of said antenna and said position location transmitter; and an alignment mechanism operatively coupled to said processing mechanism and said antenna and configured to automatically orient said antenna, based on said calibration information, and to automatically direct the oriented antenna to point to said wireless transceiver, based on directional location information of said wireless transceiver.
2. The system of Claim 1, wherein said at least one position location transmitter is selected from a plurality of position location transmitters, based on having a signal level that meets a predetermined threshold.
3. The system of Claim 2, further including a direction finding mechanism to point said antenna to said at least position location transmitter in order to determine said calibration information.
4. The system of Claim 3, wherein said directional finding mechanism comprises, a beam-forming network operatively coupled to said antenna and configured to process radiated transmit and receive beam patterns, a transceiver mechanism operatively coupled to said beam-forming network and configured to process signals to be transmitted to said beam-forming network and to process signals received from said beam-forming network, and an array of calibration antenna elements disposed on said antenna, said array of calibration antenna elements forming two orthogonal radiation beam patterns such that one of said radiation beam patterns is formed along the elevation plane and the other of said radiation beam patterns is formed along the azimuthal plane.
5. The system of Claim 4, wherein said beam-forming network forms said two orthogonal radiation beam patterns for each of the elevation and azimuthal planes, a sum beam pattern, representing a combination of said radiation beam patterns along one plane, and a difference beam pattern, representing a difference between said radiation beam patterns along the same plane.
6. The system of Claim 5, wherein said transceiver mechanism tracks said difference beam pattern for said elevation plane and azimuthal plane to determine the maximum gain along each of the planes and determine the respective elevation and azimuthal direction information associated with the maximum gain, and wherein said transceiver mechanism communicates said elevation and azimuthal direction information to said processing mechanism.
7. The system of Claim 6, wherein in response to receiving said elevation and azimuthal direction information associated with the maximum gain, said processing mechanism generates a first set of control signals, representing adjustments to be performed by said alignment mechanism, to automatically direct said antenna to point to said at least position location transmitter.
8. The system of Claim 3, wherein in response to pointing said antenna to said at least position location transmitter, said antenna location information is defined in terms of a position vector U = {ux, uy, uz) and said position location transmitter location information is defined in terms of a position vector S = {sx, sy, sz) and wherein said processing mechanism determines calibration information based on defining a vector reference space, in accordance with the following relationships: unit vector u = U/|U|, a unit vector defining a plane passing through U; unit vector r = (S-U)/|S-U|, a unit vector pointing from U to S; unit vector z =
Figure imgf000021_0001
a unit vector pointing north from the center of the earth; unit vector e = (z x U)/jz x U|, a unit vector pointing true east from U; and unit vector n = (U x e)/|U|, a unit vector pointing true north from U, wherein unit vectors u, n, and e are pair-wise orthogonal.
9. The system of Claim 8, wherein said calibration information includes an
elevation component Δθ and an azimuthal component ΔΦ and said processing mechanism
calculates said elevation component Δθ and said azimuthal component ΔΦ, in accordance
with the following relationships:
Δθ = sin"1 (r • u), where r • u is the scalar product of vectors r and u;
ΔΦ = cos"1 [ (n • p)/ I p I ], where n • p is the scalar product of vectors n
and p, and | p | is the magnitude of p; and
sign (ΔΦ) = - sign (e • p), where e • p is the scalar products of e and p,
wherein p = r - u (r • u), where p is the projection of vector r onto the
horizontal plane going through point U and u (r • u) is the product of u with the
resulting scalar product of (r • u).
10. The system of Claim 9, wherein said processing mechanism generates a second set of control signals representing orientation adjustments to be performed by said alignment mechanism to automatically orient said antenna, based on said calibration information.
11. The system of Claim 10, wherein said directional location information of said wireless transceiver comprises translating position location information of said wireless transceiver into transceiver elevation and azimuthal direction information.
12. The system of Claim 11, wherein said processing mechanism generates a third set of control signals representing directional adjustments to be performed by said alignment mechanism, based on said transceiver elevation and azimuthal direction information, to automatically direct said oriented antenna to point to said wireless transceiver.
13. A method of automatically directing a communication antenna to point to a desired wireless communication transceiver, comprising: acquiring, by a position location receiver, position location information of said antenna and at least one position location transmitter; determining, by a processing mechanism, calibration information of said antenna based on said location information of said antenna and said position location transmitter; orienting, said antenna, by an alignment mechanism, based on said calibration information; and directing the oriented antenna, by said alignment mechanism, to point to said wireless transceiver, based on directional location information of said wireless transceiver.
14. The method of Claim 13, wherein said at least one position location transmitter is selected from a plurality of position location transmitters, based on having a signal level that meets a predetermined threshold.
15. The method of Claim 14, further including, pointing said antenna to said at least position location transmitter, by a direction finding mechanism, to determine said calibration information.
16. The method of Claim 15, wherein said directional finding mechanism comprises, a beam-forming network operatively coupled to said antenna and configured to process radiated transmit and receive beam patterns, a transceiver mechanism operatively coupled to said beam-forming network and configured to process signals to be transmitted to said beam-forming network and to process signals received from said beam-forming network, and an array of calibration antenna elements disposed on said antenna, said array of calibration antenna elements forming two orthogonal radiation beam patterns such that one of said radiation beam patterns is formed along the elevation plane and the other of said radiation beam patterns is formed along the azimuthal plane.
17. The method of Claim 16, further including, forming, by said beam-forming network, a sum beam pattern, representing a combination of said orthogonal radiation beam patterns along one plane, and a difference beam pattern, representing a difference between said orthogonal radiation beam patterns along the same plane.
18. The method of Claim 17, further including, tracking, by said transceiver mechanism, said difference beam pattern for said elevation plane and azimuthal plane to determine the maximum gain along each of the planes and determine the respective elevation and azimuthal direction information associated with the maximum gain, and communicating, by said transceiver mechanism, said elevation and azimuthal direction information to said processing mechanism.
19. The method of Claim 18, further including, generating, by said processing mechanism, a first set of control signals representing adjustments to be performed by said alignment mechanism to automatically direct said antenna to point to said at least position location transmitter, in response to receiving said elevation and azimuthal direction information associated with the maximum gain.
20. The method of Claim 15, wherein in response to pointing said antenna to said at least position location transmitter, said antenna location information is defined in terms of a position vector U = {ux, uy, uz) and said position location transmitter location information is defined in terms of a position vector S = {sx, sy, sz) and wherein said processing mechanism determines calibration information based on defining a vector reference space, in accordance with the following relationships: unit vector u = U/|U|, a unit vector defining a plane passing through U; unit vector r = (S-U)/|S-U|, a unit vector pointing from U to S; unit vector z = {zx= , zy=0, zz=l), a unit vector pointing north from the center of the earth; unit vector e = (z x U)/|z x U|, a unit vector pointing true east from U; and unit vector n = (U x e)/|U|, a unit vector pointing true north from U, wherein unit vectors u, n, and e are pair- wise orthogonal.
21. The method of Claim 20, wherein said calibration information includes an
elevation component Δθ and an azimuthal component ΔΦ and said processing mechanism calculates said elevation component Δθ and said azimuthal component ΔΦ, in accordance
with the following relationships:
Δθ = sin"1 (r • u), where r • u is the scalar product of vectors r and u;
ΔΦ = cos"1 [ (n • p)/ I p I ], where n • p is the scalar product of vectors n
and p, and j p | is the magnitude of p; and
sign (ΔΦ) = - sign (e • p), where e • p is the scalar products of e and p,
wherein p = r - u (r • u), where p is the projection of vector r onto the
horizontal plane going through point U and u (r • u) is the product of u with the
resulting scalar product of (r • u).
22. The method of Claim 21, further including, generating, by said processing mechanism, a second set of control signals representing orientation adjustments to be performed by said alignment mechanism to automatically orient said antenna, based on said calibration information.
23. The method of Claim 22, wherein said directional location information of said wireless transceiver comprises translating position location information of said wireless transceiver into transceiver elevation and azimuthal direction information.
24. The method of Claim 23, further including, generating, by said processing mechanism a third set of control signals representing directional adjustments to be performed by said alignment mechanism, based on said transceiver elevation and azimuthal direction information, to automatically direct said oriented antenna to point to said wireless transceiver.
PCT/US2002/021814 2001-07-10 2002-07-09 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof WO2003007420A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
AU2002320390A AU2002320390A1 (en) 2001-07-10 2002-07-09 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof
MXPA04000347A MXPA04000347A (en) 2001-07-10 2002-07-09 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof.
KR1020047000435A KR100924245B1 (en) 2001-07-10 2002-07-09 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US30473501P 2001-07-10 2001-07-10
US60/304,735 2001-07-10
US33467501P 2001-11-15 2001-11-15
US60/334,675 2001-11-15
US10/071,928 2002-02-05
US10/071,928 US6690917B2 (en) 2001-11-15 2002-02-05 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof

Publications (2)

Publication Number Publication Date
WO2003007420A1 true WO2003007420A1 (en) 2003-01-23
WO2003007420A8 WO2003007420A8 (en) 2003-07-24

Family

ID=27371989

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2002/021814 WO2003007420A1 (en) 2001-07-10 2002-07-09 System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof

Country Status (5)

Country Link
KR (1) KR100924245B1 (en)
CN (1) CN1554136A (en)
AU (1) AU2002320390A1 (en)
MX (1) MXPA04000347A (en)
WO (1) WO2003007420A1 (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1627538A1 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of backhaul beam forming in wireless communication systems
EP1627515A2 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
EP1627516A2 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
GB2448510A (en) * 2007-04-17 2008-10-22 David Thomas Alignment of directional antenna beams to form a high gain communication link
NL2002652C2 (en) * 2009-03-23 2010-09-27 Soft Spot Consultancy B V METHOD, SYSTEM AND COMPUTER PROGRAM PRODUCT FOR DIRECTING A MOBILE FISH ANTENNA.
US8054225B2 (en) * 2006-04-20 2011-11-08 Panasonic Corporation Method and device for wireless directional beam-forming transmission
WO2014197926A1 (en) 2013-06-11 2014-12-18 E M Solutions Pty Ltd A stabilized platform for a wireless communication link
CN111162832A (en) * 2019-12-25 2020-05-15 天津海润海上技术股份有限公司 Method for realizing marine microwave directional communication based on Beidou system
AU2016222643B2 (en) * 2015-02-27 2020-10-15 Merit Medical Systems, Inc. Pressure-sensing catheters and related methods
IT202000007138A1 (en) * 2020-04-03 2021-10-03 Cinzia Uguzzoni ANTENNA FOR TELECOMMUNICATIONS
CN113993066A (en) * 2021-09-15 2022-01-28 北京电子工程总体研究所 Multidirectional directional microwave antenna alignment method and system
CN116706541A (en) * 2023-08-07 2023-09-05 中国路桥工程有限责任公司 Directional antenna alignment device of long-distance ad hoc network based on Beidou direction finding

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101621817B (en) * 2009-07-23 2011-07-27 北京格林耐特通信技术有限责任公司 Method for determining deviation of azimuth angle of base station antenna
CN102445177B (en) * 2011-09-22 2013-10-09 华为技术有限公司 Method, device and system for measuring azimuth angle and pitch angle of antenna
CN102738551B (en) * 2012-06-18 2014-10-08 西安空间无线电技术研究所 Self-adaptive amplitude and phase calibration method of spatial power combining
CN104280708B (en) * 2013-07-12 2017-05-31 中国移动通信集团广东有限公司 Microwave automatic calibrating method, device, communication emergency car and base station
CN108493611B (en) * 2018-03-21 2020-07-28 北京华力创通科技股份有限公司 Device, method and system for rapidly aligning communication-in-motion antenna and communication satellite
CN109103602A (en) * 2018-08-28 2018-12-28 中国水产科学研究院渔业机械仪器研究所 A kind of adaptive directional antenna used for fishing boat
CN111988079A (en) * 2019-05-22 2020-11-24 远传融创(杭州)科技有限公司 Information processing terminal and wireless communication method between information processing terminals
CN110045752A (en) * 2019-05-28 2019-07-23 上海电气泰雷兹交通自动化系统有限公司 Aerial position self-checking device and method
KR20220107450A (en) 2021-01-25 2022-08-02 주식회사 엑사이트 Method for automatic restoration and control of angle and tilt of wireless base station antenna
CN117134117A (en) * 2023-09-12 2023-11-28 佛山市粤海信通讯有限公司 Antenna radiation direction calibrator

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4418350A (en) * 1981-03-23 1983-11-29 Hughes Aircraft Company Two-axis antenna direction control system
US5347286A (en) * 1992-02-13 1994-09-13 Trimble Navigation Limited Automatic antenna pointing system based on global positioning system (GPS) attitude information
US5835057A (en) * 1996-01-26 1998-11-10 Kvh Industries, Inc. Mobile satellite communication system including a dual-frequency, low-profile, self-steering antenna assembly
WO1998052301A2 (en) * 1997-05-14 1998-11-19 Inmarsat Ltd Satellite apparatus with omnidirectional and manually steerable directional antenna
US6023242A (en) * 1998-07-07 2000-02-08 Northern Telecom Limited Establishing communication with a satellite

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5420597A (en) * 1991-09-12 1995-05-30 Trw Inc. Farfield simulator for testing autotrack antennas

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4418350A (en) * 1981-03-23 1983-11-29 Hughes Aircraft Company Two-axis antenna direction control system
US5347286A (en) * 1992-02-13 1994-09-13 Trimble Navigation Limited Automatic antenna pointing system based on global positioning system (GPS) attitude information
US5835057A (en) * 1996-01-26 1998-11-10 Kvh Industries, Inc. Mobile satellite communication system including a dual-frequency, low-profile, self-steering antenna assembly
WO1998052301A2 (en) * 1997-05-14 1998-11-19 Inmarsat Ltd Satellite apparatus with omnidirectional and manually steerable directional antenna
US6023242A (en) * 1998-07-07 2000-02-08 Northern Telecom Limited Establishing communication with a satellite

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1627515A2 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
EP1627516A2 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
EP1627516A4 (en) * 2003-05-16 2006-12-06 Interdigital Tech Corp Coordination of beam forming in wireless communication systems
EP1627515A4 (en) * 2003-05-16 2006-12-06 Interdigital Tech Corp Coordination of beam forming in wireless communication systems
EP1627538A4 (en) * 2003-05-16 2006-12-06 Interdigital Tech Corp Coordination of backhaul beam forming in wireless communication systems
US7197337B2 (en) 2003-05-16 2007-03-27 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
US7373176B2 (en) 2003-05-16 2008-05-13 Interdigital Technology Corporation Coordination of beam forming in wireless communication systems
US7447523B2 (en) 2003-05-16 2008-11-04 Interdigital Technology Corporation Coordination of backhaul beam forming in wireless communication systems
EP1627538A1 (en) * 2003-05-16 2006-02-22 Interdigital Technology Corporation Coordination of backhaul beam forming in wireless communication systems
US8054225B2 (en) * 2006-04-20 2011-11-08 Panasonic Corporation Method and device for wireless directional beam-forming transmission
GB2448510A (en) * 2007-04-17 2008-10-22 David Thomas Alignment of directional antenna beams to form a high gain communication link
NL2002652C2 (en) * 2009-03-23 2010-09-27 Soft Spot Consultancy B V METHOD, SYSTEM AND COMPUTER PROGRAM PRODUCT FOR DIRECTING A MOBILE FISH ANTENNA.
WO2014197926A1 (en) 2013-06-11 2014-12-18 E M Solutions Pty Ltd A stabilized platform for a wireless communication link
EP3036794A4 (en) * 2013-06-11 2017-06-14 E M Solutions Pty Ltd A stabilized platform for a wireless communication link
US10008759B2 (en) 2013-06-11 2018-06-26 E M Solutions Pty Ltd Stabilized platform for a wireless communication link
AU2016222643B2 (en) * 2015-02-27 2020-10-15 Merit Medical Systems, Inc. Pressure-sensing catheters and related methods
CN111162832A (en) * 2019-12-25 2020-05-15 天津海润海上技术股份有限公司 Method for realizing marine microwave directional communication based on Beidou system
CN111162832B (en) * 2019-12-25 2022-03-25 天津海润海上技术股份有限公司 Method for realizing marine microwave directional communication based on Beidou system
IT202000007138A1 (en) * 2020-04-03 2021-10-03 Cinzia Uguzzoni ANTENNA FOR TELECOMMUNICATIONS
CN113993066A (en) * 2021-09-15 2022-01-28 北京电子工程总体研究所 Multidirectional directional microwave antenna alignment method and system
CN116706541A (en) * 2023-08-07 2023-09-05 中国路桥工程有限责任公司 Directional antenna alignment device of long-distance ad hoc network based on Beidou direction finding

Also Published As

Publication number Publication date
AU2002320390A1 (en) 2003-01-29
KR20040010850A (en) 2004-01-31
KR100924245B1 (en) 2009-10-30
CN1554136A (en) 2004-12-08
MXPA04000347A (en) 2004-07-23
WO2003007420A8 (en) 2003-07-24

Similar Documents

Publication Publication Date Title
US6690917B2 (en) System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof
KR100924245B1 (en) System and method for automatic determination of azimuthal and elevation direction of directional antennas and calibration thereof
US10008759B2 (en) Stabilized platform for a wireless communication link
USRE37218E1 (en) Satellite-tracking millimeter-wave reflector antenna system for mobile satellite-tracking
US6462704B2 (en) Array antenna calibration
CN113438006B (en) Satellite signal capturing method, device, system and storage medium
US20080129613A1 (en) Calibration for re-configurable active antennas
US6417803B1 (en) Beam alignment system and method for an antenna
WO2010140149A1 (en) Antenna alignment method and apparatus
WO2005071430A1 (en) Transfer of calibrated time information in a mobile terminal
US8648748B2 (en) Effective marine stabilized antenna system
US10541462B2 (en) Method for elimination of antenna angular orientation error in point-to-point communication system
WO2014015169A1 (en) Ground assisted satellite antenna pointing system
CN107667486B (en) System for satellite communication
US6580391B1 (en) Antenna alignment system and method
US20240063537A1 (en) Phased Array Antenna, Scanning Method therefor, and Antenna System
US7154439B2 (en) Communication satellite cellular coverage pointing correction using uplink beacon signal
US20020067311A1 (en) Antenna system
US6300900B1 (en) Antenna for transmitting and/or receiving signals with rectilinear polarization
US20070290936A1 (en) Antenna Assembly and a Method for Satellite Tracking
US6473035B2 (en) System and method for pointing the bore-sight of a terminal antenna towards the center of a satellite station-keeping box in the geo-stationary orbit
US6608595B1 (en) Telecommunication device with shaped electronic scanning arrays and associated telecommunication terminal
US9391356B2 (en) Feature in antenna pattern for pointing and orientation determination
US7656351B1 (en) Method of designing a low cost multibeam phased array antenna for communicating with geostationary satellites
US20230163442A1 (en) Mount for coupling an antenna alignment device to an antenna with non-planar external surface

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG UZ VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LU MC NL PT SE SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
CFP Corrected version of a pamphlet front page

Free format text: UNDER (54) PUBLISHED TITLE REPLACED BY CORRECT TITLE

WWE Wipo information: entry into national phase

Ref document number: 1020047000435

Country of ref document: KR

WWE Wipo information: entry into national phase

Ref document number: PA/a/2004/000347

Country of ref document: MX

Ref document number: 68/CHENP/2004

Country of ref document: IN

WWE Wipo information: entry into national phase

Ref document number: 20028175417

Country of ref document: CN

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Ref document number: JP