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21.发明专利
公开(公告)号：AU1576701A
公开(公告)日：2001-05-14
申请号：AU1576701
申请日：2000-10-27
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
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22.发明专利
公开(公告)号：AU6361700A
公开(公告)日：2001-02-19
申请号：AU6361700
申请日：2000-07-20
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: An apparatus and method for paging a user terminal (UT) using a satellite communications system having a gateway and one or more satellites, wherein each satellite produces a plurality of beams and each beam includes a plurality of channels. The method of the present invention includes the step of recalling a location of the UT, wherein the recalled location corresponds to a location of the UT at a time t1. In one embodiment this is accomplished by performing a lookup in a table that includes location information for user terminals at different points in time. The method also includes the step of determining an area, based on the recalled location, within which the UT is assumed to be located at a time t2, where time t2 is later in time than time t1. The next step is to determine a time t3, where t3 is equal to or later in time than time t2, when the following two criteria are satisfied. First a satellite of the one or more satellites has an elevation angle between theta1 and theta2. Second, all locations within the area are located within a footprint of the satellite (that has an elevation angle between theta1 and theta2). The elevation angles theta1 and theta2 can be determined from the perspective of the recalled location. Alternatively, the elevation angle can be determined from the perspective of all locations within the area. This ensures that the UT is in the "sweet spot" of the satellite (where the gain of signals sent from the satellite are highest) when the UT is paged. A page is then sent from the gateway to the UT on a channel of a beam of the satellite at time t3. The page can be sent on a channel of every beam of a plurality of beams that make up the footprint of the satellite at time t3. Alternatively, the page can be sent on a channel of selected beams of the footprint. By waiting until the UT is within the "sweet spot" to page the UT, less power can be used by the satellite. In addition, this type of operation allows the UT to use an antenna that has a substantial gain only when the UT is within the "sweet spot". This allows the use of satellite power to be reduced further.
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公开(公告)号：AU6104500A
公开(公告)日：2001-02-13
申请号：AU6104500
申请日：2000-07-14
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method and apparatus for controlling a signal transmission power. The method of the present invention includes the steps of demodulating a received signal (401) to produce a demodulated signal (407) and distorting the demodulated signal (412) to produce a distorted demodulated signal (413). The demodulated signal (412) can be distorted by, for example, adding noise. A signal quality measurement, such as signal-to-noise ratio, is then determined (416, 418, 502, 602) based on the distorted demodulated signal rather than the demodulated signal. An adjustment in the transmission power is then requested (420, 506, 508) based on the signal quality measurement of the distorted demodulated signal.
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公开(公告)号：CA2380264A1
公开(公告)日：2001-02-01
申请号：CA2380264
申请日：2000-07-14
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method and apparatus for controlling a signal transmission power. The meth od of the present invention includes the steps of demodulating a received signa l (401) to produce a demodulated signal (407) and distorting the demodulated signal (412) to produce a distorted demodulated signal (413). The demodulate d signal (412) can be distorted by, for example, adding noise. A signal qualit y measurement, such as signal-to-noise ratio, is then determined (416, 418, 50 2, 602) based on the distorted demodulated signal rather than the demodulated signal. An adjustment in the transmission power is then requested (420, 506, 508) based on the signal quality measurement of the distorted demodulated signal.
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公开(公告)号：AU5641600A
公开(公告)日：2001-01-31
申请号：AU5641600
申请日：2000-06-22
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A system and method for spatial multiplexing signals on the feeder links of a satellite communication system. A beamforming antenna forms a plurality of feeder beams from signals received from system gateways, each feeder beam illuminating one of the gateways and including a plurality of frequency division multiple access (FDMA) channels. A plurality demultiplexers separate each of the feeder beams into the FDMA channels, and signal combiners combine first and second ones of the channels, each comprising signals corresponding to user terminals illuminated by a specific user beam, to produce a user beam signal which is used by a beamforming user link antenna to form a specific user beam. In a further aspect, a user link beamforming antenna forms a plurality of user beams from signals received from user terminals, each including a plurality of FDMA channels, and a plurality of demultiplexers separate each of the user beams into the channels. A combiner combines a first and a second one of the FDMA channels, which comprise signals corresponding to a gateway illuminated by a specific feeder beam, to produce a feeder beam signal which is used by a user link beamforming antenna to form a specific feeder beam.
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Patent Agency Ranking
公开(公告)号：CA2372952A1
公开(公告)日：2000-11-09
申请号：CA2372952
申请日：2000-05-03
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method and apparatus for paging a user terminal (UT) (124, 126) in a satellite communications system (100) having a at least one gateway (120, 12 2) and one or more satellites (116, 118), wherein each satellite produces a plurality of beams (401-416, 501-516) and each beam includes a plurality of channels, and wherein the one or more satellites (116, 118) produce a total number of beams m. The method of the present invention includes the step of recalling a location of the UT that corresponds to a known location of the U T at a time t1 (704). The method also includes the step of determining a group (g1) of beams that covers the recalled location of the UT at a time t2 (706) , where g1 t1. A strongest beam of the group (g1) of beams at time t2 is then determined (708). In one embodiment, the strongest beam is select ed by determining which beam of the group (g1) of beams theoretically has a highest power relative to the recalled location at time t2 (710). A page is then sent (712) from the gateway to the UT (124, 126) on a paging channel of the strongest beam. Accordingly, the present invention can be used to page a user terminal using a single channel of a single beam.
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公开(公告)号：CA2368415A1
公开(公告)日：2000-10-05
申请号：CA2368415
申请日：2000-03-29
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: Apparatus and method for paging a user terminal (UT) using a satellite communications system having a gateway and one or more satellites, wherein each satellite produces a plurality (n) of beams and each beam includes a plurality of channels. The method of the present invention includes the step of recalling a first location of the UT, wherein the first location corresponds to a location of the UT at a first time t1. In one embodiment, this is accomplished by performing a lookup in a table or database that includes location information for user terminals at different points in time . The method also includes the step of determining a first group (g1) of beams which covers the first location of the UT at a second time t2, where g1
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公开(公告)号：AU2022400A
公开(公告)日：2000-05-29
申请号：AU2022400
申请日：1999-11-09
Applicant: QUALCOMM INC
Inventor： ANTONIO FRANKLIN P , SCHIFF LEONARD N , AMES WILLIAM G
Abstract: The information signals are transferred to end users, customers, or service subscribers using at least two signal sources, generally satellites, and polarized radiation. Two polarization modes are employed, with the preferred modes being left-hand and right-hand circularly polarized radiation, although other polarization modes may be employed. The total number of channels can be divided among the polarization modes and transferred to end users either through the use of polarization switching in the receivers to selectively switch between the satellites, or by switching elements in the satellites (sources) to switch between polarization modes used for transmission.
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公开(公告)号：CA2348542A1
公开(公告)日：2000-05-11
申请号：CA2348542
申请日：1999-10-26
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: An apparatus and method for using a variable loop gain in a double-loop powe r control system to control the power of a forward link signal sent by a gatew ay to a user terminal to compensate for fading in a wireless communications system. In one embodiment the invention includes the steps of detecting fast fading in the forward link signal and informing the gateway of the fast fading; and at the gateway, reducing the loop gain of the power control loop when fast fading is indicated. In another embodiment, the invention includes the steps of, at the gateway, detecting fast fading in a reverse link signal received from the user terminal and reducing the loop gain of the power control loop when fast fading is indicated.
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公开(公告)号：CA2219423A1
公开(公告)日：1996-10-31
申请号：CA2219423
申请日：1996-04-22
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N , WOLF JACK K , ZEHAVI EPHRAIM
IPC: H04B7/15 , H04J3/24 , H04J11/00 , H04J13/00 , H04L1/00 , H04L12/28 , H04L12/56 , H04W72/04 , H04L12/20 , H04Q7/22 , H04B1/69
Abstract: The present invention discloses a variable rate transmission system wherein a packet of variable rate data generated by a variable rate data source (20) is modulated on traffic channel by traffic channel modulator (30) if the capacity of said traffic channel is greater than or equal to said data rate of said packet. The packet of variable rate data is modulated onto traffic channel by traffic channel modulator (30) and at least one overflow channel by traffic channel modulator (32) if the capacity of said traffic channel is less than said data rate. The present invention further discloses a receiving system for receiving variable rate data wherein a received packet of variable rate data is received on traffic channel if the capacity of said traffic channel is greater than or equal to a data rate of said packet and wherein a packet of variable rate data is received on traffic channel and at least one overflow channel if the capacity of said traffic channel is less than said data rate.
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