公开(公告)号：EP1105981B1

公开(公告)日：2008-08-27

申请号：EP99943990.4

申请日：1999-08-27

申请人： QUALCOMM INCORPORATED

发明人： CHOCKALINGAM, Ananthanarayanan ,  TENNY, Nathan, E. ,  MILLER, David, S.

IPC分类号： H04B7/216

CPC分类号： H04B7/216

摘要： A system for reducing the number of required frequency and time hypotheses to acquire an access transmission in a satellite communication system. By reducing the number of required hypotheses, the amount of hardware required to acquire the access transmission is reduced. The method of the present invention reduces the number of required hypotheses by reducing the range of possible frequency and timing values of the access transmission. The range of possible frequency and timing values is reduced by determining the frequency and time uncertainties over individual satellite beams rather than over an entire satellite footprint.

公开(公告)号：EP1008271B1

公开(公告)日：2008-08-20

申请号：EP97945252.1

申请日：1997-09-23

申请人： QUALCOMM INCORPORATED

发明人： SCHIFF, Leonard, N. ,  MILLER, David, S.

IPC分类号： H04Q7/38

CPC分类号： H04B7/18541

摘要： A handoff technique in which system users detect transitions in service between a current service area (B10, S4) and an adjacent service area (B2, S5), and request a forward link channel in the new service area (B2, S5) when a detected signal strength for the new service area exceeds predetermined threshold levels. The forward communications link in the current service area is maintained until the strength of the new service area signal (B2, S5) reaches a certain level and appropriate channel quality is confirmed, as based on various known criteria. Typically, service area transitions are detected using the signal strength of pilot or paging signals associated with service areas, which are used to determine a relative signal strength of new service area signals. Pilot signal level adjustments used to counter roll-off effects are detected and compensated for in comparing signal levels. To minimize the burden on system resources, new service area signals are not selectable until a minimum time has passed, or a minimum change in energy from a prior pilot signal is detected. In addition, communications using the previous service area can be dropped almost immediately upon engaging the new service area.

公开(公告)号：EP1525681A1

公开(公告)日：2005-04-27

申请号：EP03765995.0

申请日：2003-07-23

申请人： Qualcomm, Incorporated

发明人： SCHIFF, Leonard, N. ,  MILLER, David, S.

IPC分类号： H04B7/185

CPC分类号： H04B7/18519

摘要： A satellite communication system for providing communications between user terminals and gateways constituted with m primary satellites. In one embodiment, n back up satellites are also provided. Further, each satellite, primary or back-up, is equipped to project N/m beams onto and across an area in a loosely-packed array manner. M of the m primary and n back-up satellites collectively create N beam spots to cover the area. Moreover, each sub-area is covered by a beam spot separated from another sub-area covered by another beam spot by one beam width. Each satellite is also equipped to facilitate communication over 1 of m band of frequencies on one beam. AS a result, any of the m primary satellites may be efficiently replaced on demand by a selected one of the n back-up satellites. The gateways and user terminals are configured to communicate signals through or with both or either the primary and back-up satellites.

公开(公告)号：EP0763290B1

公开(公告)日：2003-05-28

申请号：EP96912502.0

申请日：1996-03-29

申请人： QUALCOMM Incorporated

发明人： MILLER, David, S.

IPC分类号： H04B7/26 ,  H04B7/08

CPC分类号： H04B7/0891 ,  H04B7/0845 ,  H04B7/216 ,  H04B7/2628

摘要： Method and apparatus for receiving signals in gateways for satellite repeater type spread spectrum communication systems making more efficient use of data transfer capacity and diversity processing. Several communication signals are received by multiple analog receivers (62M) and converted into digital format. The digital communication signals are transferred from each analog receiver (62M) into a series of demodulation or FHT modules (164) in which they are first despread into encoded data symbols using predetermined PN coding sequences, and then mapped into symbol energy metrics using orthogonal transformers (192), such as fast Hadamard transformers. The transformation output for each communication channel from each analog receiver (62M) is input to a single metric receiver (166N) for a data channel or subscriber, where it is subjected to conventional metric signal processing to reconstruct the data. A set of dedicated modules (164MN) is coupled to each analog receiver (62M) for handling each diversity path or subscriber active communication system channel being transferred through that receiver or analog path. Each demodulation or FHT module (164MN) comprises despreading elements (176, 178) and FHT components (192) that are easily distributed in processing arrays within the gateway.

公开(公告)号：EP1163744A1

公开(公告)日：2001-12-19

申请号：EP00919987.8

申请日：2000-03-30

申请人： QUALCOMM Incorporated

发明人： MILLER, David, S. ,  LEVANON, Nadav ,  AGRAWAL, Avneesh

IPC分类号： H04B7/185

CPC分类号： H04B7/1855 ,  G01S5/0036 ,  G01S5/12 ,  G01S2205/008

摘要： A system and method for determining a round trip delay of signals transmitted between first and second objects, such as a satellite (104) and a mobile telephone (108), that move relative to each other. A first signal is transmitted (404) from the first object (104, 108) to the second object (108, 104). The first signal is received at the second object (408) after a propagation delay D1, the delay D1 being the time taken by the first signal to traverse from the first object to the second object. A frequency of the first signal is measured (412) at the second object. The second object then transmits to the first object a second signal (416) containing a report of the measured first frequency. The second signal is received at the first object after a propagation delay D2, D2 being the time taken by the second signal to traverse from the second object to the first object. The first object measures a frequency of the second signal (424). The first object then determines the range between the first and second object (428) from the measured overall delay and the measured frequencies of the first and second signals.

公开(公告)号：EP1110335A1

公开(公告)日：2001-06-27

申请号：EP99968746.0

申请日：1999-09-08

申请人： QUALCOMM Incorporated

发明人： MILLER, David, S. ,  LORBECK, Jeffrey, A.

IPC分类号： H04B7/212

CPC分类号： H04B7/2125

摘要： A method and apparatus useful for determining the accumulated error in a user terminal clock in a satellite communications system. The satellite communications system includes a gateway, a satellite with a known position and known velocity, and a user terminal having a deskew buffer clocked by a user terminal clock. The method includes the steps of computing the one-way signal delay between the satellite and the user terminal, computing a desired deskew buffer delay based on the computed one-way signal delay and a predetermined maximum value of said one-way signal delay, and computing the accumulated error in the user terminal clock based on the desired deskew buffer delay and the actual deskew buffer delay.

公开(公告)号：EP1031196A1

公开(公告)日：2000-08-30

申请号：EP98962804.5

申请日：1998-11-10

申请人： QUALCOMM Incorporated

发明人： MILLER, David, S. ,  VIJAYAN, Rajiv ,  ZEHAVI, Ephraim ,  LEVIN, Jeffrey, A.

IPC分类号： H04B7/26 ,  H04B1/707 ,  H04B7/216

CPC分类号： H04B1/7077 ,  H04B1/70751 ,  H04B1/708 ,  H04B1/71 ,  H04B7/216 ,  H04B7/2637 ,  H04B2201/70702

摘要： The present invention is a system and method for increasing user capacity on a slotted random access channel in a spread spectrum communications system (100) by using a multi-part access probe (502). First and second parts (508, 510) of an access probe preamble (604) are modulated using a short PN code sequence (620), and the second part and remainder of the access probe (502) is modulated using a long PN code sequence. Information to be transmitted by the access probe (502) is modulated on the second part (606) of the access probe (502), and the access probe is transmitted so that the first part (508) of the probe preamble (604) falls within the boundaries of an access channel slot (402). In one embodiment, time slots (402) in access channels (400) used for access signal reception are made the length of the first part (508). In a further embodiment, time slots (402) in a plurality of adjacent access channels used for access signal reception may be longer than said first part (508) but are offset in time from each other by the length or period of the first part.

公开(公告)号：EP1008271A1

公开(公告)日：2000-06-14

申请号：EP97945252.1

申请日：1997-09-23

申请人： QUALCOMM Incorporated

发明人： SCHIFF, Leonard, N. ,  MILLER, David, S.

IPC分类号： H04Q7/38

CPC分类号： H04B7/18541

摘要： A handoff technique in which system users detect transitions in service between a current service area (B10, S4) and an adjacent service area (B2, S5), and request a forward link channel in the new service area (B2, S5) when a detected signal strength for the new service area exceeds predetermined threshold levels. The forward communications link in the current service area is maintained until the strength of the new service area signal (B2, S5) reaches a certain level and appropriate channel quality is confirmed, as based on various known criteria. Typically, service area transitions are detected using the signal strength of pilot or paging signals associated with service areas, which are used to determine a relative signal strength of new service area signals. Pilot signal level adjustments used to counter roll-off effects are detected and compensated for in comparing signal levels. To minimize the burden on system resources, new service area signals are not selectable until a minimum time has passed, or a minimum change in energy from a prior pilot signal is detected. In addition, communications using the previous service area can be dropped almost immediately upon engaging the new service area.

公开(公告)号：EP0766899B1

公开(公告)日：2003-03-12

申请号：EP95923081.4

申请日：1995-06-14

申请人： QUALCOMM INCORPORATED

发明人： MILLER, David, S.

IPC分类号： H04Q7/30

CPC分类号： H04W88/08

摘要： The invention provides a layered channel software element (200) which supervises the operation of channel element modem resources (59) in a CDMA cellular telephone system (8) that includes forward channels (20a, 22a) for conveying message and signalling data from a CDMA system base station (12) to mobile units (16, 18) and reverse channels (20b, 22b) for conveying message and signalling data from mobile units (16, 18) to base stations (12, 14). Each channel is implemented in a channel element (59) including a general purpose processor (60) and a modem application-specific integrated circuit ASIC (62). The layered channel software element (200) executes on the general processor (60). The layered channel software element (200) provides a structure and function for transferring message and signalling data between the telecommunication system (10) and the modem ASIC (62) via channel element controller (44), and also for establishing channel operations by providing channel configuration information to the modem ASIC (62).

公开(公告)号：EP1169791A1

公开(公告)日：2002-01-09

申请号：EP00919991.0

申请日：2000-03-31

申请人： QUALCOMM Incorporated

发明人： MILLER, David, S.

IPC分类号： H04B7/185

CPC分类号： H04B7/18573 ,  H04B7/18547

摘要： A methods and apparatus useful for correlating measurements of communications signals taken at base stations and gateways and user terminals in a communication system. Gateway measurements are taken at regular intervals and stored. Then, when a user terminal measurement is reported to the gateway, the gateway selects one or more stored gateway measurements that were taken nearest the time at which the user terminal measurement was taken. The gateway then applies an interpolation process using the gateway measurements to obtain a gateway measurement that roughly corresponds to the user terminal measurement. Several techniques such as extrapolation, averaging, and so forth using two or more data values can be employed as part of this process.