This invention relates to wireless communications systems, methods and devices and, more particularly, to satellite and terrestrial wireless communications systems, methods and devices.
Cellular wireless communications systems, methods and devices are widely used for voice, multimedia and/or data communications. As is well known to those having skill in the art, cellular wireless communications systems, methods and devices include terrestrial cellular wireless communications systems, methods and devices and satellite cellular wireless communications systems, methods and devices.
In cellular wireless communications systems, methods and devices, a plurality of cells are provided, each of which can serve a portion of an overall service region, to collectively provide service to the overall service region. A wireless terminal communicates with a base station (a terrestrial base station or a satellite) over bidirectional communication pathways. Wireless communication signals are communicated from the satellite or terrestrial base station over a downlink or forward link (also referred to as a “forward service link”); and wireless communications signals are communicated from the wireless terminal to the satellite or terrestrial base station over an uplink, return link or reverse link (also referred to as a “return service link”). The overall design and operation of cellular wireless communications systems, methods and devices are well known to those having skill in the art, and need not be described further herein.
As used herein, the term “wireless terminal” includes cellular and/or satellite radiotelephones with or without a multi-line display; Personal Communications System (PCS) terminals that may combine a radiotelephone with data processing, facsimile and/or data communications capabilities; Personal Digital Assistants (PDA) or smart phones that can include a radio frequency transceiver and a pager, Internet/Intranet access, Web browser, organizer, calendar and/or a global positioning system (GPS) receiver; and/or conventional laptop (notebook) and/or palmtop (netbook) computers or other appliances, which include a radio frequency transceiver. As used herein, the term “wireless terminal” also includes any other radiating user device that may have time-varying or fixed geographic coordinates and/or may be portable, transportable, installed in a vehicle (aeronautical, maritime, or land-based) and/or situated and/or configured to operate locally and/or in a distributed fashion over one or more terrestrial and/or extra-terrestrial location(s). A wireless terminal also may be referred to herein as a “radiotelephone, a “radioterminal,” a “mobile terminal,” a “wireless user device,” a “terminal,” “a handset,” a “cell phone” or variants thereof. Furthermore, as used herein, the term “satellite” includes one or more satellites at any orbit (geostationary, substantially geostationary, medium earth orbit, low earth orbit, etc.) and/or one or more other objects and/or platforms (e.g., airplanes, balloons, unmanned vehicles, space crafts, missiles, etc.) that has/have a trajectory above the earth at any altitude. Finally, the term “base station” includes any fixed, portable or transportable device that is configured to communicate with one or more wireless terminals, and includes, for example, terrestrial cellular base stations (including microcell, picocell, wireless access point and/or ad hoc communications access points) and satellites, that may be located terrestrially and/or that have a trajectory above the earth at any altitude.
Diversity combining techniques, involving multiple spaced-apart transmit and/or receive antennas, are playing an increasing role in modern wireless communication systems, in particular 3G and 4G cellular systems. While receive diversity combining has been used for many years in different forms of radio communication, more recently, transmit diversity has also been gaining in popularity.
Transmit diversity systems are generally more complex than receive diversity systems. One reason for this complexity is that, in a receive diversity system, one can collect physically separate sets of diversified samples from physically separate (i.e., spaced apart) antennas, and the samples can then be combined according to different signal processing techniques to meet desired goals, such as increasing or maximizing signal-to-noise ratio, reducing or minimizing mean squared error relative to a pilot signal, etc. In contrast, a transmit diversity system is configured to launch signals from multiple spaced-apart transmit antennas such that, at a receive antenna, the received signal quality, after signal processing, provides an improvement over that which would be obtained with a single transmit antenna. Obtaining separable copies of the channel signals at the receiver is generally more challenging for transmit diversity.
Transmit diversity techniques can be categorized as follows: (i) co-frequency signals are transmitted simultaneously from multiple transmit antennas such that the signals are separable at a receiver signal processor, the separated copies being combined according to a chosen optimization criterion (the so called “Alamouti” method); (ii) achieving separability at the receiver through frequency diversity in the transmit signals; and (iii) switched transmit diversity, where the transmit signal is selectively transmitted from one of a multiplicity of antennas. In switched transmit diversity, the transmit antenna is selected which, it is anticipated, will offer a superior channel to the receive antenna.
While techniques (i) and (ii) may offer better performances than (iii), both (i) and (ii) generally use two or more separate transmit chains, depending on the order of the diversity system. While this may not be an excessive burden in a base station, it may be much more of a burden in a wireless terminal, which may be limited in form factor and/or battery power.
Therefore, switched transmit diversity may be favored in the return links (wireless terminal to base station) of cellular and mobile satellite communication systems. In a Time Division Duplex (TDD) system, in which forward and return links can use the same frequencies at different times, strong correlation generally exists between forward and return links if the TDD frame duration (a period of time encompassing at least one cycle of forward and return transmission) is sufficiently small. In contrast, in a Frequency Division Duplex (FDD) system, in which forward and return links use different (spaced-apart) frequencies, the frequency separation between forward and return links may be too great to provide high correlation between the forward and return channel transfer functions, when the transfer function is based exclusively on a multipath profile.
The above-described difficulty in using switched transmit diversity in FDD systems is illustrated in
Referring to
In summary, for typical duplexing frequency differences, the superior channel in the forward direction will not always be the superior channel in the return direction, when the channel differences are caused primarily by the multipath profile. An implicit assumption in this practice is that the mean antenna gain, averaged over angles-of arrival relevant to the propagation scenario, are similar. This has led to the practice of not using forward-link channel estimation to determine return antenna selection in transmit diversity systems.
Various embodiments described herein can provide transmit diversity methods for a Frequency Division Duplex (FDD) wireless terminal. The FDD wireless terminal comprises a plurality of spaced-apart antennas that are configured to transmit over a return link and to receive over a forward link that is spaced apart from the return link in frequency. These transmit diversity methods comprise selectively refraining from transmitting over the return link from at least one of the plurality of spaced-apart antennas of the FDD wireless terminal in response to channel estimating of the forward link that is received at the plurality of spaced-apart antennas of the FDD wireless terminal. In some embodiments, the channel estimating of the forward link that is received at the plurality of spaced-apart antennas of the FDD wireless terminal comprises estimating differential blockages of the forward link at the plurality of spaced-apart antennas of the FDD wireless terminal that are caused, for example, by appendages of a user, such as the hand and/or head of the user, of the FDD wireless terminal. These differential blockages may be used to determine which antenna(s) should be used for switched transmit diversity purposes.
In some embodiments, the channel estimating of the forward link that is received by the plurality of spaced-apart antennas of the FDD wireless terminal comprises measuring forward link power at the plurality of spaced-apart antennas of the FDD wireless terminal over an averaging period. The averaging period may be configured by a wireless network and transmitted to the FDD wireless terminal and/or may be configured by the FDD wireless terminal itself. The differential blockages may be estimated by estimating differential gains of the plurality of spaced-apart antennas of the FDD wireless terminal, averaged over angles of arrival of the forward link.
In some embodiments, estimating differential blockages of the forward link at the plurality of spaced-apart antennas of the FDD wireless terminal may comprise determining blockage differentials among the plurality of spaced-apart antennas. In other embodiments, blockage levels may be determined at the plurality of spaced-apart antennas of the FDD wireless terminal relative to a threshold blockage level. These embodiments may include selectively refraining from transmitting over the return link from at least one of the plurality of spaced-apart antennas of the FDD wireless terminal that has a blockage level that is greater than the threshold blockage level. In other embodiments, it may be determined that all of the plurality of spaced-apart antennas of the FDD wireless terminal have blockage levels greater than the differential blockage level, and transmission may take place over an antenna of the FDD wireless terminal having a lowest blockage level. In other embodiments, it may determined that only one of the antennas has a blockage level less than the threshold blockage level, and transmitting may take place over only the one antenna of the FDD wireless terminal. In still other embodiments, it may be determined that two or more of the antennas of the FDD wireless terminal have blockage levels less than the threshold blockage level, and alternating transmission may take place over the two or more antennas of the FDD wireless terminal.
Transmit diversity methods according to various other embodiments may be used by an FDD wireless terminal. The FDD wireless terminal includes a plurality of spaced-apart antennas that are configured to transmit over a return link and to receive over a forward link that is spaced apart from the return link in frequency. The transmit diversity methods may comprise selectively refraining from transmitting over the return link from at least one of the plurality of spaced-apart antennas of the FDD wireless terminal in response to differentials in forward link power that is received at the plurality of spaced-apart antennas of the FDD wireless terminal. In some embodiments, the differentials in forward link power that is received at the plurality of spaced-apart antennas of the FDD wireless terminal are caused by blocking appendages of a user of the FDD wireless terminal.
In other embodiments, the plurality of antennas of the FDD wireless terminal consists of two antennas of the FDD wireless terminal, and selectively refraining from transmitting comprises alternating transmitting between the two antennas of the FDD wireless terminal over the return link in response to differentials in forward link power that is received at the two antennas of the FDD wireless terminal being less than a threshold, and refraining from transmitting over the return link from one of the two antennas of the FDD wireless terminal in response to differentials in forward link power that is received at the two antennas of the FDD wireless terminal exceeding the threshold.
In other embodiments, the plurality of antennas of the FDD wireless terminal comprises three or more antennas of the FDD wireless terminal, and selectively refraining from transmitting comprises alternating transmitting between at least two of the antennas of the FDD wireless terminal over the return link in response to the forward link power that is received at the at least two antennas of the FDD wireless terminal exceeding a threshold; transmitting from only one antenna of the FDD wireless terminal over the return link in response to the forward link power that is received at the only one antenna of the FDD wireless terminal exceeding the threshold; and/or transmitting from only one of the antennas of the FDD wireless terminal having a highest forward link power in response to the forward link power that is received at all of the antennas of the FDD wireless terminal being less than the threshold.
Various embodiments have been described above in connection with transmit diversity methods for FDD wireless terminals. In other embodiments, an FDD wireless terminal may comprise a plurality of spaced-apart antennas, a transmitter that is configured to transmit over a return link from the plurality of spaced-apart antennas of the FDD wireless terminal, a receiver that is configured to receive over a forward link that is spaced apart from the return link in frequency, from the plurality of spaced-apart antennas of the FDD wireless terminal, and a processor. In some embodiments, the processor is configured to control the transmitter to selectively refrain from transmitting over the return link from at least one of the plurality of spaced-apart antennas of the FDD wireless terminal in response to channel estimating of the forward link that is received at the plurality of spaced-apart antennas of the FDD wireless terminal. In other embodiments, the processor is configured to control the transmitter to selectively refrain from transmitting over the return link from at least one of the plurality of spaced-apart antennas of the FDD wireless terminal in response to differentials in forward link power that is received at the plurality of spaced-apart antennas of the FDD wireless terminal. The processor may be further configured to control the transmitter to perform operations according to the various other embodiments described above.
Specific embodiments of the invention now will be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It will be understood that when an element is referred to as being “connected”, “coupled” or “responsive” to another element, it can be directly connected, coupled or responsive to the other element or intervening elements may be present. Furthermore, “connected”, “coupled” or “responsive” as used herein may include wirelessly connected, coupled or responsive. In contrast, the term “directly” means that there are no other intervening elements.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless expressly stated otherwise. It will be further understood that the terms “includes,” “comprises,” “including” and/or “comprising,” and variants thereof when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. In contrast, the term “consisting of” and variants thereof when used in this specification, specifies the stated features, steps, operations, elements, and/or components, and precludes additional features, steps, operations, elements and/or components.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
It will be understood that although the terms first and second are used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, a first element below could be termed a second element, and similarly, a second element may be termed a first element without departing from the teachings of the present invention. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. The symbol “/” is also used as a shorthand notation for “and/or”.
The present invention is described in part below with reference to block diagrams and flowcharts of methods, systems and computer program products according to various embodiments. It will be understood that a block of the block diagrams or flowcharts, and combinations of blocks in the block diagrams or flowcharts, may be implemented at least in part by computer program instructions. These computer program instructions may execute on a processor of an FDD wireless terminal and/or a processor of a base station, such that the instructions, which execute via the processor(s) create means, modules, devices and/or methods for implementing the functions/acts specified in the block diagram block or blocks. Combinations of general purpose computer systems and/or special purpose hardware may be used in some embodiments.
These computer program instructions may also be stored in memory of the processor(s) that can direct the FDD wireless terminal and/or base station to function in a particular manner, such that the instructions stored in the memory produce an article of manufacture including computer-readable program code which implements the functions/acts specified in block or blocks. The computer program instructions may also be loaded into the processor(s) to cause a series of operational steps to be performed by the computer system(s) to produce a computer implemented process such that the instructions which execute on the processor provide steps for implementing the functions/acts specified in the block or blocks. Accordingly, a given block or blocks of the block diagrams and/or flowcharts provides support for methods, computer program products, devices and/or systems (structural and/or means-plus-function).
It should also be noted that in some alternate implementations, the functions/acts noted in the flowcharts may occur out of the order noted in the flowcharts. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved. Finally, the functionality of one or more blocks may be separated and/or combined with that of other blocks.
According to various embodiments described herein, in certain operational scenarios and using certain information processing techniques, forward channel estimation can in fact be used advantageously for return link transmit diversity.
In wireless terminals designed for use in cellular systems, the degrees of freedom available for antenna placement are often limited. The patterns of the antennas are typically irregular and may have peak gains that may not be optimum for direct line-of-sight communication with base stations. These antenna patterns may be used because a direct line-of-sight to the transmitter is generally unnecessary in terrestrial cellular links, which are designed to operate adequately with multipath signals. For example, terrestrial cell phones sometimes have patterns with peak gains pointing towards the ground. Moreover, cellular handsets are designed to operate with sufficient link margin even when the antenna is partially blocked by a hand.
There is also current interest in hybrid, terrestrial-satellite networks using common, so called “transparency devices,” which are wireless terminals that look and feel like purely cellular devices but are capable of communicating directly with satellites and/or with terrestrial base stations (ATCs) using satellite frequencies. In these hybrid systems, it is also of interest to not burden the wireless terminal with special, satellite-based requirements in terms of antenna size and layout, so as to keep the wireless terminal cost low and the aesthetics competitive with those of purely terrestrial cell phones. Thus, these hybrid wireless terminals may not use a large quadrifilar-helix antenna as is found in some legacy mobile satellite devices, or may even dispense with external antennas as is now customary with cellular handsets.
Given the cellular-driven design environment and practices described above, if two antennas are placed on a handset for implementing switched transmit diversity and used on a mobile satellite link, it is quite likely that one of the antennas would have more head and/or hand blockage than the other. This blockage is illustrated in
An architecture as illustrated in
More specifically,
In other embodiments, as illustrated in
Then, at Block 650, a difference D between the two time-averaged received signal levels Pr1 and Pr2 is calculated. A determination is then made at Block 660 as to whether D=|Pr1−Pr2| is less than a threshold value THRESHOLD. When the time-averaged, received signal levels, Pr1 and Pr2 (for example in dB) of Blocks 620 and 640, are within defined bounds of similarity, i.e., D=|Pr1−Pr2| is less than a threshold value THRESHOLD, a technique of blind switched transmit (Tx.) diversity, where no side-information is assumed, may be used at Block 680.
One technique for blind switched transmit diversity of Block 680 includes transmitting 50% of a transmit frame through one antenna 212 and the remaining 50% of the frame through the other antenna 214. In the absence of any a priori knowledge about which is instantaneously the better channel, and given that the channel will be time varying in an unpredictable way owing to multipath fading, which has been observed in field trials even for completely stationary terminals, this may be the best approach. Forward Error Correction (FEC) and soft decision combining may be used at the receiver, so that it is possible to decode a frame (up to a certain level of received signal to noise ratio) even when one half is erased owing to poor channel conditions. Other techniques may use uneven duty cycles.
In contrast, at Block 670, when it can be detected at Block 660 that Pr1 and Pr2 are quite different, perhaps owing to a combination of hand/head blockage and placement on the device (such as having the main lobe of the pattern of one antenna pointing away from the satellite and the other antenna pointing toward the satellite), it may be wasteful of transmit power to blindly put equal power in both antennas 212, 214. In such cases, the antenna receiving greater power in the forward direction is selected for return link transmission from the FDD wireless terminal at Block 670. In making the above determination, that is which antenna is receiving greater power in the forward link, time averaging may be used to average out multipath fading. The averaging period should be sufficiently long to remove slow variations owing to multipath fading but should not be excessively long so as to be unable to track likely movements of the hand/head and the user orientation relative to the base station. Additionally, the threshold value of |Pr1−Pr2| at which the diversity algorithm switches from “equal power sent to both antennas” to “pick one antenna”, may also be set optimally.
The averaging period and/or threshold parameters may be made either fixed or configurable, with the configuration being controlled by the network and downloaded to the device locally and/or remotely (over the air) and/or being controlled by the device. Configurability can allow optimum parameters to be set for different for different classes of terminals. In addition, the parameters may vary over time, for example as greater operational experience is gained.
Operations of
In these embodiments, the sets of selected (Block 716) and de-selected (Block 714) antennas, based on the received power of each relative to a threshold value (Block 712), may have more than one entry. Referring to Block 722, when more than one antenna is selected, blind switched (alternating) diversity transmission may be used for all such selected antennas, as illustrated in Block 724. All de-selected antennas are ignored for transmissions. On the other hand, if only one antenna has been selected at Block 726, then at Block 728 transmission takes place only from the one selected antenna. Finally, if no antennas have been selected at Block 726, indicating that all antennas have power below the threshold, the antenna with the highest power is selected for transmission continuous, ignoring the threshold value, at Block 732.
Accordingly, various embodiments described herein can operate in a frequency division duplex wireless communication system, involving a forward link and a return link at a duplex frequency spacing, and can provide methods, devices and systems of switched, return-link transmit diversity involving transmissions for a user device having a multiplicity of antennas, where forward-link channel estimation is used as a basis for selecting the transmit antenna on the device. The channel estimation may involve measuring the forward link power over an averaging period, where the averaging period is configurable by the network, wherein the configurability is achieved locally by the device, and/or where the configurability is achieved remotely, including over-the-air downloading of the configuration parameter(s).
The channel estimation may include estimating the differential gains of the antennas on the user device, averaged over all angles-of-arrival relevant to the reception of the forward link transmission, thereby detecting cases of differential blockage faced by the antennas. The antennas may be divided into a set having blockage below a threshold value and those having blockage greater than a threshold value. Antennas having blockage greater than a threshold value are deselected from the list of antennas used for return-link transmissions, except for the case where all antennas have blockage greater than the threshold, in which case the antenna with the least blockage may be selected for transmission. Where only one antenna is in the list of antennas with blockage below the threshold value, that antenna may be selected for transmission. Finally, where more than one antenna is in the list of antennas with blockage below the threshold value, all such antennas may be used for blind transmission using any switched diversity method that does not use a priori knowledge of the condition of the channel from the selected antennas to the receiver.
Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.
In the drawings and specification, there have been disclosed embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.
This application claims the benefit of U.S. Provisional Application No. 61/257,913, filed Nov. 4, 2009, the disclosure of which is hereby incorporated herein by reference in its entirety as if set forth fully herein.
Number | Name | Date | Kind |
---|---|---|---|
4901307 | Gilhousen et al. | Feb 1990 | A |
5073900 | Mallinckrodt | Dec 1991 | A |
5303286 | Wiedeman | Apr 1994 | A |
5339330 | Mallinckrodt | Aug 1994 | A |
5394561 | Freeburg | Feb 1995 | A |
5446756 | Mallinckrodt | Aug 1995 | A |
5448623 | Wiedeman et al. | Sep 1995 | A |
5475677 | Arnold et al. | Dec 1995 | A |
5511233 | Otten | Apr 1996 | A |
5555257 | Dent | Sep 1996 | A |
5584046 | Martinez et al. | Dec 1996 | A |
5612703 | Mallinckrodt | Mar 1997 | A |
5619525 | Wiedeman et al. | Apr 1997 | A |
5631898 | Dent | May 1997 | A |
5761605 | Tawil et al. | Jun 1998 | A |
5765098 | Bella | Jun 1998 | A |
5812947 | Dent | Sep 1998 | A |
5832379 | Mallinckrodt | Nov 1998 | A |
5835857 | Otten | Nov 1998 | A |
5848060 | Dent | Dec 1998 | A |
5852721 | Dillon et al. | Dec 1998 | A |
5878329 | Mallinckrodt | Mar 1999 | A |
5884142 | Wiedeman et al. | Mar 1999 | A |
5907541 | Fairholm et al. | May 1999 | A |
5926758 | Grybos et al. | Jul 1999 | A |
5937332 | Karabinis | Aug 1999 | A |
5940753 | Mallinckrodt | Aug 1999 | A |
5991345 | Ramasastry | Nov 1999 | A |
5995832 | Mallinckrodt | Nov 1999 | A |
6011951 | King et al. | Jan 2000 | A |
6023605 | Sasaki et al. | Feb 2000 | A |
6052560 | Karabinis | Apr 2000 | A |
6052586 | Karabinis | Apr 2000 | A |
6067442 | Wiedeman et al. | May 2000 | A |
6072430 | Wyrwas et al. | Jun 2000 | A |
6085094 | Vasudevan et al. | Jul 2000 | A |
6091933 | Sherman et al. | Jul 2000 | A |
6097752 | Wiedeman et al. | Aug 2000 | A |
6101385 | Monte et al. | Aug 2000 | A |
6108561 | Mallinckrodt | Aug 2000 | A |
6134437 | Karabinis et al. | Oct 2000 | A |
6157811 | Dent | Dec 2000 | A |
6157834 | Helm et al. | Dec 2000 | A |
6160994 | Wiedeman | Dec 2000 | A |
6169878 | Tawil et al. | Jan 2001 | B1 |
6198730 | Hogberg et al. | Mar 2001 | B1 |
6198921 | Youssefzadeh et al. | Mar 2001 | B1 |
6201967 | Goerke | Mar 2001 | B1 |
6233463 | Wiedeman et al. | May 2001 | B1 |
6240124 | Wiedeman et al. | May 2001 | B1 |
6253080 | Wiedeman et al. | Jun 2001 | B1 |
6256497 | Chambers | Jul 2001 | B1 |
6324405 | Young et al. | Nov 2001 | B1 |
6339707 | Wainfan et al. | Jan 2002 | B1 |
6418147 | Wiedeman | Jul 2002 | B1 |
6449461 | Otten | Sep 2002 | B1 |
6522865 | Otten | Feb 2003 | B1 |
6628919 | Curello et al. | Sep 2003 | B1 |
6684057 | Karabinis | Jan 2004 | B2 |
6735437 | Mayfield et al. | May 2004 | B2 |
6775251 | Wiedeman et al. | Aug 2004 | B1 |
6785543 | Karabinis | Aug 2004 | B2 |
6856787 | Karabinis | Feb 2005 | B2 |
6859652 | Karabinis et al. | Feb 2005 | B2 |
6879829 | Dutta et al. | Apr 2005 | B2 |
6892068 | Karabinis et al. | May 2005 | B2 |
6937857 | Karabinis | Aug 2005 | B2 |
6975837 | Santoru | Dec 2005 | B1 |
6999720 | Karabinis | Feb 2006 | B2 |
7006789 | Karabinis et al. | Feb 2006 | B2 |
7031702 | Karabinis et al. | Apr 2006 | B2 |
7039400 | Karabinis et al. | May 2006 | B2 |
7062267 | Karabinis | Jun 2006 | B2 |
7092708 | Karabinis | Aug 2006 | B2 |
7107021 | Kim et al. | Sep 2006 | B2 |
7113743 | Karabinis | Sep 2006 | B2 |
7113778 | Karabinis | Sep 2006 | B2 |
7155340 | Churan | Dec 2006 | B2 |
7174127 | Otten et al. | Feb 2007 | B2 |
7181161 | Karabinis | Feb 2007 | B2 |
7203490 | Karabinis | Apr 2007 | B2 |
7218931 | Karabinis | May 2007 | B2 |
7295807 | Karabinis | Nov 2007 | B2 |
7340213 | Karabinis et al. | Mar 2008 | B2 |
7418236 | Levin et al. | Aug 2008 | B2 |
7418263 | Dutta et al. | Aug 2008 | B2 |
7421342 | Churan | Sep 2008 | B2 |
7437123 | Karabinis et al. | Oct 2008 | B2 |
7444170 | Karabinis | Oct 2008 | B2 |
7447501 | Karabinis | Nov 2008 | B2 |
7453396 | Levin et al. | Nov 2008 | B2 |
7453920 | Churan | Nov 2008 | B2 |
7454175 | Karabinis | Nov 2008 | B2 |
7457269 | Grayson | Nov 2008 | B1 |
7558568 | Karabinis | Jul 2009 | B2 |
7574206 | Karabinis | Aug 2009 | B2 |
7577400 | Karabinis et al. | Aug 2009 | B2 |
7587171 | Evans et al. | Sep 2009 | B2 |
7593691 | Karabinis | Sep 2009 | B2 |
7593724 | Karabinis | Sep 2009 | B2 |
7593725 | Karabinis | Sep 2009 | B2 |
7593726 | Karabinis et al. | Sep 2009 | B2 |
7596111 | Karabinis | Sep 2009 | B2 |
7599656 | Karabinis | Oct 2009 | B2 |
7603081 | Karabinis | Oct 2009 | B2 |
7603117 | Karabinis | Oct 2009 | B2 |
7606590 | Karabinis | Oct 2009 | B2 |
7609666 | Karabinis | Oct 2009 | B2 |
7620394 | Good et al. | Nov 2009 | B2 |
7623859 | Karabinis | Nov 2009 | B2 |
7623867 | Karabinis | Nov 2009 | B2 |
7627285 | Karabinis | Dec 2009 | B2 |
7634229 | Karabinis | Dec 2009 | B2 |
7634234 | Karabinis | Dec 2009 | B2 |
7636546 | Karabinis | Dec 2009 | B2 |
7636566 | Karabinis | Dec 2009 | B2 |
7636567 | Karabinis et al. | Dec 2009 | B2 |
7636573 | Walton et al. | Dec 2009 | B2 |
7639981 | Karabinis | Dec 2009 | B2 |
7653348 | Karabinis | Jan 2010 | B2 |
7660598 | Barnett et al. | Feb 2010 | B2 |
7664460 | Karabinis et al. | Feb 2010 | B2 |
8654715 | Wang et al. | Feb 2014 | B2 |
9755710 | Murakami | Sep 2017 | B2 |
9929794 | Rowland | Mar 2018 | B2 |
20020122408 | Mullins | Sep 2002 | A1 |
20020146979 | Regulinski et al. | Oct 2002 | A1 |
20020177465 | Robinett | Nov 2002 | A1 |
20030003815 | Yamada | Jan 2003 | A1 |
20030149986 | Mayfield et al. | Aug 2003 | A1 |
20040072539 | Monte et al. | Apr 2004 | A1 |
20040102156 | Loner | May 2004 | A1 |
20040121727 | Karabinis | Jun 2004 | A1 |
20040203393 | Chen | Oct 2004 | A1 |
20040235433 | Hugl et al. | Nov 2004 | A1 |
20040240525 | Karabinis et al. | Dec 2004 | A1 |
20050041619 | Karabinis et al. | Feb 2005 | A1 |
20050090256 | Dutta | Apr 2005 | A1 |
20050095987 | Lyons et al. | May 2005 | A1 |
20050118948 | Karabinis et al. | Jun 2005 | A1 |
20050136836 | Karabinis et al. | Jun 2005 | A1 |
20050164700 | Karabinis | Jul 2005 | A1 |
20050164701 | Karabinis et al. | Jul 2005 | A1 |
20050181786 | Karabinis et al. | Aug 2005 | A1 |
20050201449 | Churan | Sep 2005 | A1 |
20050227618 | Karabinis et al. | Oct 2005 | A1 |
20050239399 | Karabinis | Oct 2005 | A1 |
20050260947 | Karabinis et al. | Nov 2005 | A1 |
20050260984 | Karabinis | Nov 2005 | A1 |
20050265273 | Karabinis et al. | Dec 2005 | A1 |
20050272369 | Karabinis et al. | Dec 2005 | A1 |
20050288011 | Dutta | Dec 2005 | A1 |
20060040613 | Karabinis et al. | Feb 2006 | A1 |
20060072524 | Perahia | Apr 2006 | A1 |
20060094420 | Karabinis | May 2006 | A1 |
20060111041 | Karabinis | May 2006 | A1 |
20060111056 | Dutta | May 2006 | A1 |
20060135058 | Karabinis | Jun 2006 | A1 |
20060135070 | Karabinis | Jun 2006 | A1 |
20060165120 | Karabinis | Jul 2006 | A1 |
20060189275 | Karabinis | Aug 2006 | A1 |
20060194576 | Karabinis et al. | Aug 2006 | A1 |
20060205347 | Karabinis | Sep 2006 | A1 |
20060205367 | Karabinis | Sep 2006 | A1 |
20060211452 | Karabinis | Sep 2006 | A1 |
20060217070 | Karabinis | Sep 2006 | A1 |
20060246838 | Karabinis | Nov 2006 | A1 |
20060252368 | Karabinis | Nov 2006 | A1 |
20060292990 | Karabinis et al. | Dec 2006 | A1 |
20070010246 | Churan | Jan 2007 | A1 |
20070015460 | Karabinis et al. | Jan 2007 | A1 |
20070021059 | Karabinis et al. | Jan 2007 | A1 |
20070021060 | Karabinis et al. | Jan 2007 | A1 |
20070037514 | Karabinis | Feb 2007 | A1 |
20070072545 | Karabinis et al. | Mar 2007 | A1 |
20070099562 | Karabinis et al. | May 2007 | A1 |
20070123252 | Tronc et al. | May 2007 | A1 |
20070129019 | Otten et al. | Jun 2007 | A1 |
20070135051 | Zheng et al. | Jun 2007 | A1 |
20070184849 | Zheng | Aug 2007 | A1 |
20070192805 | Dutta et al. | Aug 2007 | A1 |
20070202816 | Zheng | Aug 2007 | A1 |
20070232298 | Karabinis | Oct 2007 | A1 |
20070243866 | Karabinis | Oct 2007 | A1 |
20070281612 | Benjamin et al. | Dec 2007 | A1 |
20070293214 | Ansari et al. | Dec 2007 | A1 |
20080008264 | Zheng | Jan 2008 | A1 |
20080032671 | Karabinis | Feb 2008 | A1 |
20080032690 | Karabinis | Feb 2008 | A1 |
20080113666 | Monte et al. | May 2008 | A1 |
20080119190 | Karabinis | May 2008 | A1 |
20080151798 | Camp | Jun 2008 | A1 |
20080160993 | Levin et al. | Jul 2008 | A1 |
20080182572 | Tseytlin et al. | Jul 2008 | A1 |
20080214207 | Karabinis | Sep 2008 | A1 |
20080268836 | Karabinis et al. | Oct 2008 | A1 |
20090011704 | Karabinis | Jan 2009 | A1 |
20090029696 | Karabinis | Jan 2009 | A1 |
20090040100 | Levin et al. | Feb 2009 | A1 |
20090042509 | Karabinis et al. | Feb 2009 | A1 |
20090042516 | Karabinis | Feb 2009 | A1 |
20090075645 | Karabinis | Mar 2009 | A1 |
20090088151 | Karabinis | Apr 2009 | A1 |
20090104903 | Karabinis | Apr 2009 | A1 |
20090131046 | Karabinis et al. | May 2009 | A1 |
20090137203 | Karabinis et al. | May 2009 | A1 |
20090156154 | Karabinis et al. | Jun 2009 | A1 |
20090170427 | Karabinis | Jul 2009 | A1 |
20090170428 | Karabinis | Jul 2009 | A1 |
20090170429 | Karabinis | Jul 2009 | A1 |
20090186622 | Karabinis | Jul 2009 | A1 |
20090231187 | Churan | Sep 2009 | A1 |
20090264120 | Karabinis | Oct 2009 | A1 |
20090296628 | Karabinis | Dec 2009 | A1 |
20090305697 | Karabinis et al. | Dec 2009 | A1 |
20090312013 | Karabinis | Dec 2009 | A1 |
20100015971 | Good et al. | Jan 2010 | A1 |
20100035605 | Karabinis | Feb 2010 | A1 |
20100035606 | Karabinis | Feb 2010 | A1 |
20100246516 | Pelletier et al. | Sep 2010 | A1 |
20100322328 | Schirmacher | Dec 2010 | A1 |
20110044376 | Lin | Feb 2011 | A1 |
20120002630 | Bergman et al. | Jan 2012 | A1 |
20120009968 | Kludt et al. | Jan 2012 | A1 |
20120294384 | Wilcoxson | Nov 2012 | A1 |
20140079155 | Wang et al. | Mar 2014 | A1 |
Number | Date | Country |
---|---|---|
0 506 255 | Sep 1992 | EP |
0 506 255 | Sep 1992 | EP |
0 597 225 | May 1994 | EP |
0 506 255 | Nov 1996 | EP |
0 748 065 | Dec 1996 | EP |
0 755 163 | Jan 1997 | EP |
0 762 669 | Mar 1997 | EP |
0 762 669 | Mar 1997 | EP |
0 797 319 | Sep 1997 | EP |
0 831 599 | Mar 1998 | EP |
0 831 599 | Mar 1998 | EP |
1 059 826 | Dec 2000 | EP |
1 193 989 | Apr 2002 | EP |
1 463 215 | Sep 2004 | EP |
1 715 600 | Oct 2006 | EP |
1 906 553 | Apr 2008 | EP |
1 944 885 | Jul 2008 | EP |
1 569 363 | Nov 2008 | EP |
2 015 467 | Jan 2009 | EP |
WO 0154314 | Jul 2001 | WO |
Entry |
---|
Written Opinion of the International Preliminary Examining Authority, PCT Application No. PCT/US2010/054907, dated Nov. 22, 2011. |
Global.com, “Globalstar Demonstrates World's First Prototype of Terrestrial System to Supplemental Satellite Phones,” http://www.globalcomsatphone.com/globalcom/globalstar_terrestrial_system.html, Jul. 18, 2002, 2 pages. |
Ayyagari et al., “A satellite-augmented cellular network concept”, Wireless Networks, Vo. 4, 1998, pp. 189-198. |
International Preliminary Report on Patentability, PCT Application No. PCT/US2010/054907, dated Jan. 12, 2012. |
Notification of Transmittal of the International Search Report and the Written Opinion of the International Searching Authority, or the Declaration; International Search Report; Written Opinion of the International Searching Authority corresponding to International Application No. PCT/US2010/054907; dated Feb. 21, 2011; 14 pages. |
GeekInterview.com, “What is 1×EV-DV Standard”, downloaded May 13, 2013 from http://www.learn.geekinterview.com/it/wireless/what-is-1xev-dv-standard.html, 2 pp. |
Number | Date | Country | |
---|---|---|---|
20110103273 A1 | May 2011 | US |
Number | Date | Country | |
---|---|---|---|
61257913 | Nov 2009 | US |