公开(公告)号：AU2003243678A8

公开(公告)日：2004-01-06

申请号：AU2003243678

申请日：2003-06-20

Applicant: QUALCOMM INC

Inventor： JALALI AHMAD ,  SCHIFF LEONARD N

IPC: H04B7/185 ,  H04B7/216 ,  H04B7/26

Abstract: Orthogonal CDMA (OCDMA) in the return link of a satellite based communications system provides improved bandwidth efficiencies; increased ability to overcome channel degrading phenomenon; reduced transmission power; or various combinations thereof. By achieving code synchronization needed for advantageous use of OCDMA in the return link of a satellite based communication system, a plurality of terminals, each with a unique time slot/code channel assignment, may transmit concurrently, with the same, or lower, aggregate power as would be used by a single terminal using TDMA. Use of OCDMA in the return link allows one or more terminals, each in a common beam and assigned a common time slot, to transmit at a higher transmission power to overcome channel degradation effects. The ability to allow for higher transmission power for a particular terminal can increase the effective data rate for that terminal by enabling the use of a higher order modulation technique.

公开(公告)号：AU2003243678A1

公开(公告)日：2004-01-06

申请号：AU2003243678

申请日：2003-06-20

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N ,  JALALI AHMAD

IPC: H04B7/185 ,  H04B7/216 ,  H04B7/26 ,  H04B7/005

Abstract: Orthogonal CDMA (OCDMA) in the return link of a satellite based communications system provides improved bandwidth efficiencies; increased ability to overcome channel degrading phenomenon; reduced transmission power; or various combinations thereof. By achieving code synchronization needed for advantageous use of OCDMA in the return link of a satellite based communication system, a plurality of terminals, each with a unique time slot/code channel assignment, may transmit concurrently, with the same, or lower, aggregate power as would be used by a single terminal using TDMA. Use of OCDMA in the return link allows one or more terminals, each in a common beam and assigned a common time slot, to transmit at a higher transmission power to overcome channel degradation effects. The ability to allow for higher transmission power for a particular terminal can increase the effective data rate for that terminal by enabling the use of a higher order modulation technique.

公开(公告)号：CA2380555A1

公开(公告)日：2001-02-22

申请号：CA2380555

申请日：2000-08-16

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N

IPC: H04B7/15 ,  H04B7/185 ,  H04B7/26 ,  H04J13/00 ,  H04L7/00

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 step s of generating a paging channel message which is combined with a Walsh sequen ce having a length greater than or equal to 2m, 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.

公开(公告)号：CA2380603A1

公开(公告)日：2001-02-08

申请号：CA2380603

申请日：2000-07-20

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N

IPC: H04B7/185 ,  H04B7/204

Abstract: An apparatus and method for paging a user terminal (UT) using a satellite communications system having a gateway (120, 122) and one or more satellites (116, 118), wherein each satellite produces a plurality of beams (401-416) a nd each beam includes a plurality of channels. The method of the present invention includes the step of recalling a location of the UT (124, 126), wherein the recalled location corresponds to a location of the UT at a time t1 (904). The method also includes the step of determining an area, based on th e recalled location, within which the UT (124, 126) is assumed to be located a t a time t2 (906), 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 (908). First a satellite of th e one or more satellites has an elevation angle between .theta.1 and 02. Secon d, all locations within the area are located within a footprint (400) of the satellite (that has an elevation angle between .theta.1 and .theta.2). The elevation angles .theta.1 and .theta.2 can be determined from the perspectiv e of the recalled location. Alternatively, the elevation angle can be determin ed from the perspective of all locations within the area. This ensures that the UT (124) is in the "sweet spot" (518, 522) of the satellite (116) (where the gain of signals sent from the satellite are highest) when the UT (124) is paged. By waiting until the UT is within the "sweet spot" to page the UT, le ss power can be used by the satellite (116).

公开(公告)号：AU3931700A

公开(公告)日：2000-10-16

申请号：AU3931700

申请日：2000-03-29

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N

IPC: H04B7/26 ,  H04B7/185 ,  H04Q7/38

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

公开(公告)号：CA2349170A1

公开(公告)日：2000-05-18

申请号：CA2349170

申请日：1999-11-09

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N ,  AMES WILLIAM G ,  ANTONIO FRANKLIN P

IPC: H04J11/00 ,  H04B7/06 ,  H04B7/10 ,  H04B7/185 ,  H04J3/00

Abstract: The information signals are transferred to end users, customers, or service subscribers (116, 118) using at least two signal sources, generally satellit es (104, 106), and polarized radiation. Two polarization modes are employed, wi th the preferred modes being left-hand and right-hand circularly polarized radiation, although other polarization modes may be employed. The total numb er of channels can be divided among the polarization modes and transferred to e nd users either through the use of polarization switching in the receivers (522 ) to selectively switch between the satellites, or by switching elements in th e satellites (sources) to switch between polarization modes used for transmission.

公开(公告)号：AU6407999A

公开(公告)日：2000-04-17

申请号：AU6407999

申请日：1999-09-29

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N

IPC: H04J13/00 ,  H04B7/185 ,  H04B7/195

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.

公开(公告)号：AU5219799A

公开(公告)日：2000-02-14

申请号：AU5219799

申请日：1999-07-21

Applicant: QUALCOMM INC

Inventor： ANTONIO FRANKLIN P ,  MARSH GENE W ,  STEWART RICHARD A ,  BJEREDE MARIE M ,  CHOCKALINGAM ANANTHANARAYANAN ,  KERNS ARTHUR S ,  BUTLER BRIAN ,  GROB MATTHEW S ,  DETERMAN JAMES T ,  GROVER DOUGLAS ,  SCHIFF LEONARD N ,  AMES WILLIAM G

IPC: H04B7/26 ,  H04B7/02 ,  H04B7/185 ,  H04Q7/36

Abstract: A method for reducing call dropping rates in a multi-beam communication system. The multi-beam communication system includes a user terminal, a gateway, and a plurality of beam sources, where each beam source projects a plurality of beams, and where a communication link between the user terminal and the gateway is established on one or more beams. The method according to the present invention relies on a messaging protocol between the gateway and the user terminal. Based on messages sent from the user terminal to the gateway, preferably on a preselected periodic basis, the gateway can determine the more desirable beam(s) for transmitting data or information to the user terminal. The messages sent from the user terminal to the gateway contain values representing beam strengths as measured at the user terminal. The gateway uses the user terminal measured beam strengths to select the beams that should be used for transmitting data or information to the user terminal. The beams that should be used are the beams that if used will decrease the call dropping rates and provide a desired level of beam source diversity.

公开(公告)号：AU4649897A

公开(公告)日：1998-04-17

申请号：AU4649897

申请日：1997-09-23

Applicant: QUALCOMM INC

Inventor： SCHIFF LEONARD N ,  MILLER DAVID S

IPC: H04W16/24 ,  H04W36/14 ,  H04Q7/38

公开(公告)号：MX9708267A

公开(公告)日：1998-02-28

申请号：MX9708267

申请日：1996-04-22

Applicant: QUALCOMM INC

Inventor： ZEHAVI EPHRAIM ,  WOLF JACK K ,  SCHIFF LEONARD N

IPC: H04B7/15 ,  H04J3/24 ,  H04J11/00 ,  H04J13/00 ,  H04L1/00 ,  H04L12/28 ,  H04L12/56 ,  H04W72/04

Abstract: La presente invencion revela un sistema de transmision de velocidad variable, en donde un paquete de datos de velocidad de transmision variable generado por una fuente (20) de datos de velocidad de transmision variable se modula sobre el canal de tráfico mediante el modulador (309 de canal de tráfico, en caso de que la capacidad del canal de tráfico sea superior o igual a la velocidad de transmision de datos del paquete. El paquete de datos de velocidad de transmision variable se modula sobre el canal de tráfico mediante el modulador (30) de canal de tráfico y por lo menos un canal de sobreflujo mediante el modulador (32) de canal de tráfico, en caso de que la capacidad del canal de tráfico sea menor a la mencionada velocidad de transmision de datos. La presente invencion también expone un sistema receptor para recibir datos de velocidad de transmision variable, en donde un paquete recibido de los datos de velocidad de transmision variable se reciben sobre el canal de tráfico en caso de que la capacidad del canal de tráfico sea mayor o igual a una velocidad de transmision de datos del paquete y en donde un paquete de datos de velocidad de transmision variable se recibe sobre el canal de tráfico y por lo menos un canal de sobreflujo, en caso de que la capacidad del canal de tráfico sea menor a la velocidad de transmision de datos.