KR100897838B1 - Satellite communication subscriber device with a smart antenna and associated method - Google Patents

Abstract

The satellite communication subscriber device includes a smart antenna for generating antenna beams for receiving signals from at least one satellite and a receiver. The receiver includes a quality metric module for calculating a quality metric on the signals received by each antenna beam. The beam selector is coupled to the smart antenna to select the antenna beams. The antenna steering algorithm module operates a beam selector to scan antenna beams, receives the calculated quality metric from a receiver for each scanned antenna beam, and executes an antenna steering algorithm to compare the calculated quality metric. . The algorithm selects one of the scanned antenna beams based on the comparison to continue receiving signals from at least one satellite.

Satellite communications, quality metrics, multipath, antenna steering

Description

SATELLITE COMMUNICATION SUBSCRIBER DEVICE WITH A SMART ANTENNA AND ASSOCIATED METHOD

TECHNICAL FIELD The present invention relates to the field of satellite communications subscriber devices, and more particularly to a smart antenna that provides angular diversity with respect to signals received from satellites and / or terrestrial repeaters to select a preferred signal source. It is about.

In satellite digital wireless systems, audio signals are digitized and transmitted from satellites using digital communication techniques such as digital modulation and coding. Satellite digital radio systems provide benefits not available in conventional AM or FM analog radio systems. Digital compression technology allows satellite digital radio systems to provide high quality audio signals even when signals are received in a moving vehicle. High quality audio reproduction is not generally possible with conventional AM or FM analog radio systems.

In satellite digital radio reception, in particular, signal degradation due to multipath fading, which is essentially a deviation in RF signal levels due to multiple random signal reflections, is annoying. Although baseband digital transmission techniques such as equalization and modulation can reduce the effects of multipath fading, degradation still exists.

In particular, severe signal degradation can occur when the satellite digital radio receiver is indoors or in narrow inter-building passages. Digital signals from orbiting satellites may not be obtained with a good line-of-sight path. As a result, various random reflections of satellite-originated signals, i.e., multipath, may be the only signal that a satellite digital wireless receiver radio can receive.

Several transmission redundancy techniques, collectively referred to as diversity techniques, are used in current satellite digital radio systems to reduce the impact on wireless reception caused by degradation such as multipath fading or other types of signal blocking. The first technique is satellite spatial diversity, in which two or more satellites transmit the same signals from remotely spaced locations. Second is frequency diversity, in which different satellites transmit the same signal in different frequency bands. The third technique is time diversity, in which different satellites transmit the same signal at slightly different times. In hard-to-reach areas such as dense urban centers or signal blocking structures such as tunnels, satellite digital radio signals are retransmitted at separate frequencies using terrestrial repeaters.

Current subscriber device antenna systems utilize suitable omni-directional antennas when relatively strong line-of-sight signals are available from either satellite or terrestrial repeaters. However, omnidirectional antennas are very vulnerable in multipath environments, such as within buildings or narrow inter-building locations in dense urban areas. One fixed beam antenna has no way of determining the direction in which the reflected radio signal can be best received and cannot be oriented to detect more accurately and receive in any particular direction.

In addition, current antenna systems use dual element antennas, commonly referred to as diversity antennas. Although performance may be improved in certain situations, dual element antennas are sensitive to multipath fading due to the symmetrical nature of the hemispherical lobes formed by the antenna pattern. The signal reflected back from its source can be received at about the same power as the original signal received directly. That is, if the original signal is reflected from an object beyond the intended receiver (from the sender's point of view) or from an object behind the intended receiver and reflected back toward the intended receiver from the opposite direction of the directly received signal, The phase difference may create a multipath fading situation.

It is also common to point a fixed directional high gain antenna towards the satellite, i.e. a typical outdoor antenna. Because these antennas have a fixed pointing angle, they will not be suitable for receiving signals in a multipath environment where a reflected signal that is not in the direction of the direct satellite path may be the best signal.

Another problem is the reception of signals retransmitted by terrestrial repeaters, which can be interfered by nearby transmission systems. Although these signals are separated in the frequency spectrum, adjacent channels may still experience interference from nearby transmitter stations. As a result, omni-directional antennas and dual element diversity antennas are not suitable in a multipath environment.

In view of the foregoing background, it is an object of the present invention to improve the reception by communications subscriber devices of signals transmitted by satellites and / or terrestrial repeaters in a multipath environment.

These and other objects, features, and advantages according to the present invention provide a smart antenna for generating a plurality of antenna beams for receiving signals from at least one satellite, and a quality metric on the signals received by each antenna beam. Provided by a satellite communication subscriber device comprising a receiver comprising a quality metric module for calculating.

The beam selector is coupled to the smart antenna to select a plurality of antenna beams. The antenna steering algorithm module includes operating a beam selector to scan a plurality of antenna beams, receiving a calculated quality metric from a receiver for each scanned beam antenna, and comparing the calculated quality metric. Implement an antenna steering algorithm for The algorithm selects one of the scanned antenna beams based on the comparison above to continue receiving signals from at least one satellite.

The calculated quality metric is compared to the low quality metric threshold and for the calculated quality metric falling below the low quality metric threshold, the corresponding corresponding antenna beam is ignored when making the selection. The calculated quality metric can include a received signal strength indicator or a signal-to-noise ratio of the received signal. Alternatively, the calculated quality metric may include the error rate or data throughput of the received signal.

In a first embodiment, the plurality of antenna beams may comprise a plurality of directional antenna beams and an omnidirectional antenna beam. In a second embodiment, the plurality of antenna beams may comprise orthogonal polarization beams, ie linear or circular beams. Also, the third embodiment may include a combination of the first and second embodiments.

The antenna steering algorithm can operate the beam selector to scan the plurality of antenna beams. The smart antenna may include a switched beam antenna or a phased array antenna, or any other antenna architecture that provides selectable beams, such as a dual quadrature polarizing antenna, or an antenna that provides a selectable linear or circular beam. Can be.

In addition, the antenna steering algorithm selects the omnidirectional antenna beam prior to scanning the plurality of directional antenna beams, receives a quality metric calculated from the receiver for the signal received by the omnidirectional beam antenna, and receives the plurality of directionalities. The beam selector is operated to compare the calculated quality metric with a scan threshold to determine whether antenna beams should be scanned.

In addition, the antenna steering algorithm receives the quality metric calculated for the received signals from the receiver and compares the calculated quality metric with a scan threshold to determine which directional beams will be scanned. Operate the beam selector to sequentially select all or a subset thereof.

The smart antenna advantageously generates directional antenna beams in azimuthal and elevation directions. Since the smart antenna may receive a signal from at least one terrestrial repeater, the smart antenna selects directional antenna beams in azimuth and elevation angles for the beam selector to receive a signal from the at least one terrestrial repeater, and at least one Allows selection of directional antenna beams in azimuth and elevation directions to receive a signal from a satellite of the antenna.

The satellite communications subscriber device may further comprise a transmitter for transmitting signals from the smart antenna. The antenna steering algorithm may operate the beam selector during scanning such that only some of the plurality of antenna beams are scanned based on the known direction of at least one satellite.

By providing asymmetrical directivity and consequently angular diversity in the azimuth or elevation direction, or both, the satellite communication subscriber device of the present invention not only provides the problem of unavailability of signal diversity of a single element omni-directional antenna system. In addition, we solve the problem of inability to random multipath fading due to the fixed symmetric beam pattern of the dual element diversity antenna system. In addition, the antenna beams can be directed toward the desired transmitter source, away from unwanted interference from adjacent broadcast signals.

Another aspect of the invention relates to a method for operating a satellite communications subscriber device as described above. The method includes operating a beam selector to scan a plurality of antenna beams, receiving a calculated quality metric from a receiver for each scanned antenna beam, comparing the calculated quality metric, and a satellite Or selecting one of the scanned antenna beams based on the comparison to continue receiving a signal from the terrestrial repeater.

1 is a schematic diagram of a satellite digital radio system including a phase communication subscriber device according to the present invention.

2 is a block diagram of the satellite communication subscriber device shown in FIG.

3 is a flow chart for operating the satellite communications subscriber device shown in FIG.

4 is a schematic diagram of one embodiment of the smart antenna shown in FIG.

FIG. 5 is a schematic diagram of another embodiment of the smart antenna shown in FIG. 4 that includes reactive load elements that are independently adjustable to provide directional and steerable antenna beams.

FIG. 6 is a schematic diagram of a partial side of the ground plane shown in FIG. 5 with a variable reactive load inserted between two parallel plates to provide an steerable antenna beam in an elevation direction.

FIG. 7 is a schematic diagram of another embodiment of the smart antenna shown in FIG. 1 including a Shelton-Butler metric fed to a pair of arrays.

FIG. 8 is a three-dimensional view of the directional antenna beams in the azimuth and elevation angles generated by the smart antenna shown in FIG. 7.

With reference to the accompanying drawings, in which preferred embodiments of the invention are shown, the invention will be described in detail below. However, the present invention should not be limited to the embodiments presented herein, but may be embodied in many different forms. Rather, these embodiments are provided so that they will fully convey the scope of the invention to those skilled in the art. Like parts are designated by like reference numerals throughout the drawings, and prime notation is used to indicate like elements in alternative embodiments.

First, referring to FIGS. 1 and 2, a satellite digital wireless system 10 will be discussed. The satellite digital wireless system 10 includes one or more satellites 12 that transmit digital wireless signals to a satellite communication device, such as a satellite communication subscriber device 16. Subscriber device 16 may be mobile or stationary. The terrestrial repeater 14 may be used to retransmit digital wireless signals. Subscriber device 16 operates in conjunction with subscriber-based smart antenna 18. The smart antenna 18 can be a switched beam antenna or a phased array antenna, as described in more detail below.

Subscriber device 16 and smart antenna 18 are compatible with at least one of a variety of digital wireless satellites such as, for example, a Sirius wireless satellite, an XM wireless satellite, or a WorldSpace satellite. When receiving wireless signals from any one of these digital wireless satellites, subscriber device 16 only needs to operate in a receive-only mode. However, in a two-way satellite communication system, subscriber device 16 should be able to transmit signals to satellite 12 and / or terrestrial repeater, as will be readily understood by those skilled in the art.

Since subscriber device 16 is operating within building 20, this results in a multipath signal-rich environment. In this example, the satellite 12 is at an elevation of about 45 to 60 degrees with respect to the subscriber device 16. Antenna beams 22 from two satellites 12 direct the transmitted signals into the building 20 at different angles. In addition, signals from satellite 12 are retransmitted by the terrestrial repeater 14 into the building 20 via an omni-directional antenna beam or an azimuth antenna beam 24.

Inside the building 20 and around the subscriber device 16, a plurality of reflected signal paths 26 for transmitted signals are shown. That is, the subscriber device undergoes multipath fading in signal reception. The illustrated smart antenna 18 generates a directional antenna beam 28 to receive an optimal signal based on the multipath reflected signal.

Signals from satellite 12 may provide spatial diversity, frequency diversity through the use of different frequency bands, and time diversity through the use of time delay. As discussed in more detail below, satellite 12 and terrestrial repeater 14 may operate on a shared spectrum (eg, using time division multiplexing), and may use (eg, frequency division multiplexing) May operate on separate spectra). Current satellite systems use TDM-QPSK modulation for satellite transmission of signals. The terrestrial repeater 14 uses TDM-COFDM modulation for terrestrial retransmission of the signal.

The antenna beams generated by the smart antenna 18 include directional beams 30 and omni-directional beams 32. In addition, the antenna beams may comprise orthogonal polarization beams, ie linear or circular beams. In addition to the smart antenna 18 being a phased array antenna or a switched beam antenna, the smart antenna may be any other antenna providing selectable beams, such as a dual quadrature polarizing antenna or an antenna providing a selectable linear or circular beam. It may include an architecture.

Subscriber device 16 includes beam selector 40 coupled to smart antenna 18 for selecting antenna beams 30, 32. When the smart antenna 18 is a satellite array antenna, more than one directional antenna beam may be generated at a time.

The transceiver 42 is coupled to the beam selector 40 to receive signals from the satellite 12 and the ground repeater 14. Antenna steering algorithm module 44 executes antenna steering algorithm 46 to determine which antenna beam provides the best reception. The selected antenna beam that provides the best reception corresponds to one of the satellites 12 or terrestrial repeater 14. Since the antenna beams may have different polarizations, the selection of the best antenna will be based on which polarization provides the best reception.

Instead of being separated from the transceiver 42 and the beam selector 40 as shown, the antenna steering algorithm module 44 may reside within the beam selector or transceiver, as will be readily appreciated by those skilled in the art. Antenna steering algorithm 46 operates beam selector 40 to scan the plurality of antenna beams 30, 32 to receive signals from satellite 12 and terrestrial repeater 14.

The quality metric module 48 in the transceiver 42 calculates a quality metric for the signals received by each scanned antenna beam, and the quality metrics are then compared by the antenna steering algorithm 46. Based on the comparison, one of the scanned antenna beams is selected to continue receiving signals from its associated satellite 12 and terrestrial repeater 14. Since the scanned antenna beams may have different polarizations, the quality metric is also determined based on reception with the different polarizations.

The calculated quality metric is compared to the low quality metric threshold, and for the calculated quality metric falling below the low quality metric threshold, the corresponding corresponding antenna beam is ignored when making the selection. The calculated quality metric may be a signal quality metric.

The signal quality metric can include a received signal strength indicator or a signal-to-noise ratio of the received signal. Alternatively, the calculated quality metric may be a link quality metric such as data throughput or error rate of the received signal. The calculated quality metric may also be a combination of one of the signal quality metrics with one of the link quality metrics.

The method for operating the smart antenna 18 will now be discussed with reference to the flowchart shown in FIG. 3. From initiation (block 60), the omni-directional antenna beam 32 is selected at block 62 to receive the transmitted signal for the first time. A quality metric is calculated for the signals received via the omni-directional antenna beam 32, and the calculated quality metric is compared to the scan threshold at block 64. A decision is then made at block 66 as to whether to perform scanning on the plurality of directional antenna beams 30. In case the smart antenna 16 cannot generate the omni-directional antenna beam 32, one of the directional antenna beams 30 is selected and used.

If the scanning decision is "yes", a plurality of directional antenna beams 30 are scanned at block 68 and a quality metric is calculated at block 70 on the signals received by each scanned antenna beam. At block 72, the calculated quality metrics are compared.

After the directional antenna beams 30 have been scanned, another determination is made at block 74 to determine if the calculated quality metric is optimized. If smart antenna 18 is a switched beam antenna, this optimization is based on selecting a scanned antenna beam that receives the signal with the highest quality metric.

In addition, the calculated quality metric will be compared to the low quality metric threshold as described above. For a calculated quality metric that falls below the low quality metric threshold, the associated corresponding antenna beam is ignored when performing scanning.

If the smart antenna 180 is a phased array antenna, switched beam antenna or simultaneous multi-polarization antenna, more than one antenna beam may be generated at a time. In this case, multiple antenna beams may be generated at the same time to receive different multipath signals. Optimization of the quality metric is based on the phase alignment of the selected antenna beams, resulting in the reception of the signal with the best quality metric. Since the received signals are vector signals each having a phase and an amplitude, the signals are added to or subtracted from each other, as those skilled in the art will readily understand. This is especially true when satellite 12 and terrestrial repeater 14 operate on the same channel.

As an example, the scanned antenna beam receiving the signals with the highest quality metric can be further optimized when the smart antenna 18 also receives a signal, for example from two other antenna beams. Here, these two different antenna beams are added (not subtracted) to the signals with the best quality metric. Depending on the number of antenna beams that can be generated, a predetermined combination of antenna beams can be combined to know which combination of phases align the received multipath signals.

If the quality metric is optimized, one of the directional antenna beam (s) is selected at block 76 and communication with the corresponding satellite 12 and terrestrial repeater 14 continues. At block 78, a determination is made to determine whether or not a scan needs to be performed. Such rescan may be based on a time periodic rescan, or a signal received via the selected antenna beam (s) falling below the rescan threshold. In some cases, it may be desirable to reset the smart antenna 18 at block 80 and start all together with the omni-directional antenna beam 32. For example, the subscriber device 16 may need to be powered on and then powered back on, or receive a signal from the terrestrial repeater 14 as the subscriber device passes through the tunnel. This method ends at block 82.

Another advantage of generating multiple antenna beams simultaneously with a phased array smart antenna is when different channels are being used by satellite 12 and terrestrial repeater 14. For example, one of the satellites 12 is transmitting a signal on channel 1, the other satellite is transmitting a signal on channel 2, and the terrestrial repeater 14 is transmitting a signal on channel 3. By generating three antenna beams at the same time, each antenna beam can be directed towards each source, and based on the calculated quality metric, the antenna beam is selected that provides the signal with the highest quality metric. In addition, the retrieved or scanned directional antenna beam 30 will be a limited set based on the known directions of the satellite 12 and the terrestrial repeater 14.

Different embodiments of the smart antenna 18 will be discussed with reference to FIGS. 4 to 8. One embodiment of the smart antenna 18 includes four antenna elements 90, 92 lying on a planar triangular ground 94 as shown in FIG. 4. Three of the antenna elements 90 lie at the corner of the triangular ground 94, and one of the antenna elements 92 lie at the center of the triangular ground 94. The depicted shape of the ground 94 and the illustrated number of antenna elements 90, 92 may vary depending on the intended application, as those skilled in the art will readily appreciate.

In one form of a switched beam antenna, the three outer antenna elements 90 are passive and the central antenna element 92 is active. Passive elements 90 operate with active element 92 to form an array. In order to change the radiation pattern, the termination impedance of the passive elements 90 is switchable to change the current flowing through these elements. Passive elements 90 become reflectors when shorted to ground 94 using, for example, a pin diode. When passive elements 90 are not shorted to ground 94, they have little effect on antenna characteristics.

In yet another embodiment, the antenna elements 90 and 92 are both active elements and are combined with an independently adjustable phase shifter to provide a phased array antenna. In this embodiment, a plurality of directional beams as well as omnidirectional beams in the azimuth direction can be generated.

In essence, the phased array antenna includes a plurality of antenna elements and a somewhat smaller but similar number of adjustable phase shifters. Each of the phase shifters is associated with each one of the antenna elements. Phase shifters are independently adjustable (ie programmable) to affect the phase of each downlink / uplink signal received / transmitted on each of the antenna elements.

A summation circuit is also coupled to each phase shifter to provide each uplink signal from subscriber device 16 to each phase shifter for transmission from the subscriber device. The summing circuit also receives each downlink signal from each phase shifter and combines it into one received downlink signal provided to the subscriber device 16.

The phase shifter is also independently adjustable to affect the phase of the downlink signals received on each antenna element of the subscriber device 16. By adjusting the phase for the downlink links, the smart antenna 18 provides for rejection of signals that are not transmitted from a similar direction as downlink signals intended for the subscriber device 16 as the received signal.

Another embodiment of the smart antenna 18 'is shown in FIG. 5, where the three antenna elements 90' located at the corners of the triangular ground 94 'are the upper halves 90 ₁ ' of the antenna elements. And at the lower half 90 ₂ ′, they have independently adjustable reactive load elements. Such an embodiment may provide a plurality of beams that are directed in the azimuth and / or elevation direction.

Independently adjustable reactive load elements include varactor or mechanically insertable RF choke elements, for example, to provide an asymmetrical load on the antenna elements. As a result, antenna beams that are directed in the elevation direction are formed.

Another embodiment of the ground 94 "is shown in Figure 6. Here, a variable edge impedance 96" is inserted between two parallel plates 100 ", 102" of the ground 94 ". Edge impedance 96 "may be a varactor load for controlling the edge impedance, resulting in an upward or downward tilt angle in the elevation angle of the generated antenna beams. A plurality of reactive loads can be placed on the ground 94 "to approximate a continuous wall of reactance, and the values of reactance at different locations can be different, so the beam tilt angle is also azimuth Can be a function of

Yet another embodiment of the smart antenna 18 "is shown in FIG. 7, where one row of the elevation Shelton-Butler metric 120" is isolated narrow elevation angle beams (as shown in FIG. 8). 124 ") are fed to two or more stacked circular arrays 122". Each circular array 122 "is also fed by two Shelton-Butler metric 130" longitudinally, such that the antenna beams are defined as pencil beams. The azimuth beam distribution has a 3-dB crossover, and the elevation beams can be designed to have different crossover values. The resulting beams provide a plurality of highly differentiated antenna look patterns at the elevation angle as well as at the azimuth angle. Through port selection, the beam direction can be changed electronically.

When smart antenna 18 is configured as a phased array antenna to adapt to various orientations with respect to satellite 12 or terrestrial repeater 14, beam selector 40 includes a controller coupled to each of the adjustable phase shifters. . The controller determines the optimal phase setting for each phase shifter. The appropriate phase of each element is, for example, optimal for time division multiplexed (TDM) pilot signals transmitted in TDM-QPSK (for satellite transmission) or TDM-COFDM signals (for terrestrial repeater transmission). It is determined by monitoring the response. Thus, the smart antenna 18 serves as a beamformer for signal transmission from the transceiver 42 and acts as a directional antenna for the signals received by the transceiver.

By using an array of antenna elements each having a programmable phase, the antenna device increases the effective transmit power per bit transmitted for uplink communication by 5-12 decibels (dB), depending on the N antenna elements. It is assumed to make. Thus, the transmit power of the subscriber device 16 can be reduced without sacrificing uplink performance. Also, when used in the receive mode, the received signal quality can be improved in the downlink. As a result, the perceived quality of the wireless audio signal can be improved.

When used indoors, or in other multipath environments where the direct line of sight paths from the direct satellite link are weak or unavailable, the directivity of the smart antenna 18 can achieve high reception performance in poor multipath environments. To gather available energy from the plurality of reflected radio paths. The directivity of the smart antenna 18 also allows the subscriber device 16 to suppress unwanted or unwanted interference from a given direction, thereby improving wireless performance over the desired link.

With regard to the physical implementation of the smart antenna 18 described above, out of a total of N antenna elements, the first N-1 antenna elements are arranged at positions corresponding to the corners of the equilateral polygon, and the last antenna element of the ground plane of the polygon. Placed in the center. All N elements are vertically aligned with respect to the plane defined by the polygon. In such embodiments, the smart antenna shows beams that have essentially the same pattern in the elevation direction and can be distinguished as directional or omnidirectional beams in the azimuth direction.

In addition, by employing high gain directional beams, wireless link performance is reduced when there is a clear line of sight radio path between the digital radio signal transmitter (ie, satellite 12 or terrestrial repeater 14) and subscriber device 16. Significantly improved. More specifically, the directivity is provided not only in the azimuth direction but also in the elevation direction, providing an optimal approach for improved wireless performance for subscriber devices receiving signals from satellites in orbit.

From the teaching of the drawings in conjunction with the above description, many modifications and other embodiments of the invention will be apparent to those skilled in the art. Accordingly, the invention should not be limited to the specific embodiments disclosed, and such modifications and embodiments are intended to be included within the scope of the appended claims.

Claims (31)

A satellite communication subscriber device, Switched beam antenna comprising an active antenna element and a plurality of passive antenna elements for generating a plurality of antenna beams for receiving signals from at least one satellite, at least some of the plurality of antenna beams Has different polarizations; A receiver comprising a quality metric module for calculating a quality metric for the signals received by each antenna beam; A beam selector coupled to the switched beam antenna, for selecting the plurality of antenna beams based on a selective change in termination impedance of the plurality of passive antenna elements; And Antenna steering algorithm module for executing antenna steering algorithm Including, the antenna steering algorithm, Based on the known direction of the at least one satellite, operate the beam selector to scan some of the plurality of antenna beams, Receive the calculated quality metric from the receiver for each scanned antenna beam, Compare the calculated quality metric, And select one of the scanned antenna beams based on the comparison to continue receiving signals from the at least one satellite. The method of claim 1, wherein the calculated quality metric is also compared to a low quality metric threshold, and for a calculated quality metric that falls below the low quality metric threshold, corresponding antenna beams associated with the quality metric are selected from one of the antenna beams. Being ignored when making a selection. delete 2. The satellite communications subscriber device of claim 1 wherein the different polarizations comprise at least one of linear and circular polarizations. 2. The satellite communications subscriber device of claim 1 wherein the calculated quality metric comprises at least one of a received signal strength indicator and a signal-to-noise ratio of the received signal. 2. The satellite communications subscriber device of claim 1 wherein the calculated quality metric comprises at least one of a data throughput and an error rate of the received signal. 2. The satellite communications subscriber device of claim 1 wherein the plurality of antenna beams comprises a plurality of directional antenna beams and an omni-directional antenna beam. 8. The satellite communications subscriber device of claim 7 wherein the antenna steering algorithm operates the beam selector to scan the plurality of directional antenna beams. 10. The system of claim 8, wherein the antenna steering algorithm selects the omni-directional antenna beam prior to scanning the plurality of directional antenna beams and further calculates a quality metric calculated for the signals received by the omni-directional antenna beam. Operating the beam selector to receive from the receiver and to compare the calculated quality metric with a scan threshold to determine whether the plurality of directional antenna beams should be scanned. 2. The satellite communications subscriber device of claim 1 wherein the plurality of antenna beams comprise only a plurality of directional antenna beams. 2. The satellite communications subscriber device of claim 1 wherein the switched beam antenna generates a plurality of directional antenna beams and an omnidirectional antenna beam. delete 2. The satellite communications subscriber device of claim 1 wherein the switched beam antenna generates directional antenna beams in azimuthal and elevation directions. The antenna of claim 13, wherein the switched beam antenna further receives signals from at least one terrestrial repeater and the beam selector receives the directional antenna beams in the azimuthal direction to receive signals from the at least one terrestrial repeater. And select the directional antenna beams in the elevation direction to receive signals from the at least one satellite. 2. The satellite communications subscriber device of claim 1 further comprising a transmitter for transmitting signals from the switched beam antenna. delete A satellite communication subscriber device, A phased array antenna comprising a plurality of active antenna elements for generating a plurality of directional antenna beams in azimuth and elevation directions, the plurality of directional beams receiving signals from at least one of a satellite and a terrestrial repeater. The phased array antenna, wherein at least some of the plurality of antenna beams have different polarizations; A transceiver comprising a quality metric module for calculating a quality metric for signals received by each directional antenna beam; A beam selector coupled to the phased array antenna for selecting the plurality of directional antenna beams in the azimuth and elevation directions based on selective adjustment of the phase associated with each active antenna element; And Antenna steering algorithm module for executing the antenna steering algorithm Including, the antenna steering algorithm, Operate the beam selector to scan some of the plurality of antenna beams based on a known direction of at least one of the satellite and terrestrial repeater, Receive the calculated quality metric from the transceiver for each scanned antenna beam, Compare the calculated quality metric, And select one of the scanned directional antenna beams in the azimuth or elevation direction based on the comparison to continue receiving signals from the satellite or terrestrial repeater. 18. The method of claim 17, wherein the calculated quality metric is also compared to a low quality metric threshold, and for a calculated quality metric that falls below the low quality metric threshold, corresponding antenna beams associated with the quality metric are selected from one of the directional antenna beams. Being ignored when making a selection. 18. The satellite communications subscriber device of claim 17 wherein the calculated quality metric comprises at least one of a received signal strength indicator and a signal-to-noise ratio of the received signal. 18. The apparatus of claim 17, wherein the calculated quality metric comprises at least one of data throughput and error rate of the received signal. 18. The antenna of claim 17, wherein the phased array antenna also generates an omnidirectional antenna beam, the antenna steering algorithm selects the omnidirectional antenna beam prior to scanning the plurality of directional antenna beams, and further comprises the omnidirectional antenna. To receive a quality metric calculated for the signals received by an antenna beam from the transceiver and compare the calculated quality metric with a scan threshold to determine whether the plurality of directional antenna beams should be scanned: Operating the beam selector. delete delete A switched beam antenna comprising an active antenna element and a plurality of passive antenna elements for generating a plurality of antenna beams for receiving signals from at least one satellite, and a quality for the signals received by each antenna beam 24. A method for operating a satellite communications subscriber device comprising a receiver comprising a quality metric module for calculating a metric, the switched beam antenna coupled beam selector, and an antenna steering algorithm module for executing an antenna steering algorithm. , Operating the beam selector to scan some of the plurality of antenna beams based on a known direction of the at least one satellite, wherein the scanning is based on a selective change in termination impedance of the plurality of passive antenna elements ; Receiving the calculated quality metric from the receiver for each scanned antenna beam; Comparing the calculated quality metric; And Selecting one of the scanned antenna beams based on the comparison to continue receiving signals from the at least one satellite And a method for operating a satellite communications subscriber device. 25. The method of claim 24, wherein the calculated quality metric is also compared to a low quality metric threshold, and for a calculated quality metric that falls below the low quality metric threshold, corresponding antenna beams associated with the quality metric among the scanned antenna beams. Which is ignored when making one selection. delete The satellite of claim 24, wherein the calculated quality metric comprises at least one of a received signal strength indicator, a signal-to-noise ratio of the received signal, a data throughput of the received signal, and an error rate. A method for operating a communications subscriber device. 25. The method of claim 24, wherein the plurality of antenna beams comprises a plurality of directional antenna beams and an omnidirectional antenna beam. 29. The system of claim 28, wherein the antenna steering algorithm operates the beam selector to select the omni-directional antenna beam prior to scanning the plurality of directional antenna beams, Receiving from the receiver a quality metric calculated for the signals received by the omni-directional antenna beam; Comparing the calculated quality metric with a scan threshold to determine whether the plurality of directional antenna beams should be scanned Further comprising a satellite communications subscriber device. 25. The method of claim 24, wherein the switched beam antenna generates directional antenna beams in azimuthal and elevation directions. 31. The method of claim 30, wherein the switched beam antenna further receives signals from at least one terrestrial repeater, and the beam selector selects the directional antenna beams in azimuthal direction to receive signals from the at least one terrestrial repeater. And selecting said directional beams in an elevation direction to receive signals from said at least one satellite.

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