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公开(公告)号：AT307431T
公开(公告)日：2005-11-15
申请号：AT00957567
申请日：2000-08-16
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method for deep paging in a communication system employing orthogonal channelizing codes, such as Walsh sequences, of predetermined length m, that does not require a high powered paging channel. The method includes the steps of generating a paging channel message which is combined with a Walsh sequence having a length greater than or equal to 2 m , and transmitting the paging channel message at a data rate of less than 480 bits per second (bps). By transmitting the paging channel message at a low data rate and integrating collected energy over a period longer by a factor on the order of 1000, the message is able to penetrate buildings and other structures or high attenuation environments, thereby allowing one to successfully page a user terminal that is inside such a structure or area. Preferably, the paging channel message is formed using an auxiliary Walsh sequence on the order of 65536 chips in length, and the data rate is less than 10 bps.
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公开(公告)号：AU2005223266A1
公开(公告)日：2005-09-29
申请号：AU2005223266
申请日：2005-03-15
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
IPC: H04B7/185
Abstract: Communication diversity using a plurality of satellites is disclosed. The satellites can support multiple regions corresponding to multiple satellite beams. Each satellite can support all regions in the reverse direction and each satellite can be designated as a primary satellite for one of the multiple regions corresponding to one of the multiple satellite beams. Each satellite can receive from any of the regions reverse link signals broadcast by, for example, a mobile station. Each satellite can communicate the received reverse link signals to, for example, a base station or gateway where the signals can be combined to increase signal quality. A mobile station receives forward link signals from the primary satellite and monitors a signal quality from the primary satellite and from a secondary satellite. If the signal quality from the primary satellite drops below a threshold value, the communication signal is transferred to the secondary satellite.
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公开(公告)号：AT283583T
公开(公告)日：2004-12-15
申请号：AT99951692
申请日：1999-09-29
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method and apparatus for transmitting common information to a plurality of user terminals within a geographic region. The method and apparatus are useful in a satellite communication system (100) having a gateway (120, 122), and a plurality of satellites (116, 118) that orbit such that they are not stationary with respect to a point on the surface of the Earth. The method includes the step of generating a list identifying a plurality of common data channels (702) over which the common information will be transmitted. The list can include, for each of said plurality of common data channels, information identifying a predetermined satellite, beam (401-416), frequency, and channel. Due to the orbiting of the satellites (116, 118), the list changes over time. The method also includes the steps of transmitting (708), from the gateway to the geographic region (502, 504, 520, 522), the common information on the plurality of common data channels. The method also includes receiving (720), at a user terminal (124, 126), the common information over at least one of the plurality of common data channels.
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公开(公告)号：AU2004203066A1
公开(公告)日：2004-07-29
申请号：AU2004203066
申请日：2004-07-08
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
IPC: H04B7/185
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公开(公告)号：AU2004203062A1
公开(公告)日：2004-07-29
申请号：AU2004203062
申请日：2004-07-08
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
IPC: H04B7/185
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Patent Agency Ranking
公开(公告)号：AU2003278762A1
公开(公告)日：2004-01-06
申请号：AU2003278762
申请日：2003-06-24
Applicant: QUALCOMM INC
Inventor： MILLER DAVID S , SCHIFF LEONARD N
Abstract: A technique for realizing code synchronism to enable the application of modulation codes needed for implementing orthogonal CDMA modulation for reverse link communications. In a satellite communications system using orthogonal CDMA in the reverse link, a ground station transmits a first pilot signal in the forward link direction, which is acquired and tracked by a terminal or remote station, and used in recovering carrier phase and modulation chip clock timing. The terminal then derives a transmission carrier frequency and chip clock timing to be used, from the recovered forward pilot carrier frequency and chip clock timing. The terminal transmits a second pilot signal in the reverse link direction which, after being received and retransmitted by a satellite, is detected at the ground station. Terminals have the ability to advance or retard the timing of their signals for transmission relative to the timing derived from the forward link pilot signal. The ground station tracks timing, and in some embodiments also tracks frequency, of the terminal pilot signal, and compares these parameters to a reverse link reference signal. Based at least in part on the results of the comparison, the ground station transmits a control signal on the forward link to each terminal, thereby commanding the terminal to advance or retard its respective transmission timing. Each terminal then adjusts its transmission timing and/or frequency in small increments to maintain a desired level of time alignment with the ground station.
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公开(公告)号：AU2003247631A1
公开(公告)日：2004-01-06
申请号：AU2003247631
申请日：2003-06-25
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A satellite is linked to a number of gateways by a number of feeder links. When a degraded link is detected among the feeder links, communications are switched from the degraded link to a diversity link shared among the feeder links. In one embodiment, the diversity link is connected to a diversity gateway located outside a service area of the satellite. In another embodiment, the diversity link comprises channels distributed among the feeder links within the service area.
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公开(公告)号：CA2490527A1
公开(公告)日：2003-12-31
申请号：CA2490527
申请日：2003-06-25
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A satellite is linked to a number of gateways by a number of feeder links. When a degraded link is detected among the feeder links, communications are switched from the degraded link to a diversity link shared among the feeder links. In one embodiment, said diversity link is connected to a diversity gateway located outside a service area of the satellite. In another embodiment, the diversity link comprises channels distributed among the feed er links within the service area.
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公开(公告)号：AU758680B2
公开(公告)日：2003-03-27
申请号：AU1235000
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 power control system to control the power of a forward link signal sent by a gateway 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：HK1048206A1
公开(公告)日：2003-03-21
申请号：HK03100198
申请日：2003-01-08
Applicant: QUALCOMM INC
Inventor： SCHIFF LEONARD N
Abstract: A method for deep paging in a communication system employing orthogonal channelizing codes, such as Walsh sequences, of predetermined length m, that does not require a high powered paging channel. The method includes the steps of generating a paging channel message which is combined with a Walsh sequence having a length greater than or equal to 2 m , and transmitting the paging channel message at a data rate of less than 480 bits per second (bps). By transmitting the paging channel message at a low data rate and integrating collected energy over a period longer by a factor on the order of 1000, the message is able to penetrate buildings and other structures or high attenuation environments, thereby allowing one to successfully page a user terminal that is inside such a structure or area. Preferably, the paging channel message is formed using an auxiliary Walsh sequence on the order of 65536 chips in length, and the data rate is less than 10 bps.
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