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公开(公告)号：DE69531096T2
公开(公告)日：2004-04-08
申请号：DE69531096
申请日：1995-09-27
Applicant: QUALCOMM INC
Abstract: An integrated search processor used in a modem for a spread spectrum communications system buffers receive samples and utilizes a time sliced transform processor operating on successive offsets from the buffer. The search processor autonomously steps through a search as configured by a microprocessor specified search parameter set, which can include the group of antennas to search over, the starting offset and width of the search window to search over, and the number of Walsh symbols to accumulate results at each offset. The search processor calculates the correlation energy at each offset, and presents a summary report of the best paths found in the search to use for demodulation element reassignment. This reduces the searching process related workload of the microprocessor and also reduces the modem costs by allowing a complete channel element modem circuit to be produced in a single IC.
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公开(公告)号：DE69918313T2
公开(公告)日：2005-09-29
申请号：DE69918313
申请日：1999-08-13
Applicant: QUALCOMM INC
Abstract: A method and apparatus for compressing fixed point signals without introducing a bias. Signals are compressed according to a dithered rounding approach wherein signal values are rounded up and rounded down with approximately equal probability, canceling the bias that would otherwise result from the rounding operation. Numerical properties of the input signal are exploited in order to determine whether the signal value should be rounded up or down. Signal compression may, therefore, be introduced at multiple points within a system without accumulating a signal bias and degrading downstream performance. Further, one bit signal compression may be achieved in a particularly efficient fashion with a minimal amount of hardware.
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公开(公告)号：DE69928003D1
公开(公告)日：2005-12-01
申请号：DE69928003
申请日：1999-12-09
Applicant: QUALCOMM INC
IPC: H04B1/7117 , H04B1/7115 , H04B1/712 , H04B7/26 , H04B1/707
Abstract: A wireless receiver receiving multipath Wash-code symbols determines which of fingers 402, 410 have locked on a signal. Measurements of the correlation energies between the received signal and all possible symbols are stored in energy storage units 404, 412. The actual signals are combined in combiner 408. A maximum determiner 416 determines the most likely combined symbol, and an index for this symbol is fed back to the energy storage units. Lock detectors 406, 414 use the measurement for this fed-back symbol to determine whether the finger has locked onto a path. This determination is used to decide whether the next signal detected by that finger should be applied to the combiner.
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公开(公告)号：DE69918313D1
公开(公告)日：2004-07-29
申请号：DE69918313
申请日：1999-08-13
Applicant: QUALCOMM INC
Abstract: A method and apparatus for compressing fixed point signals without introducing a bias. Signals are compressed according to a dithered rounding approach wherein signal values are rounded up and rounded down with approximately equal probability, canceling the bias that would otherwise result from the rounding operation. Numerical properties of the input signal are exploited in order to determine whether the signal value should be rounded up or down. Signal compression may, therefore, be introduced at multiple points within a system without accumulating a signal bias and degrading downstream performance. Further, one bit signal compression may be achieved in a particularly efficient fashion with a minimal amount of hardware.
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Patent Agency Ranking
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公开(公告)号：DE69531096D1
公开(公告)日：2003-07-24
申请号：DE69531096
申请日：1995-09-27
Applicant: QUALCOMM INC
Abstract: An integrated search processor used in a modem for a spread spectrum communications system buffers receive samples and utilizes a time sliced transform processor operating on successive offsets from the buffer. The search processor autonomously steps through a search as configured by a microprocessor specified search parameter set, which can include the group of antennas to search over, the starting offset and width of the search window to search over, and the number of Walsh symbols to accumulate results at each offset. The search processor calculates the correlation energy at each offset, and presents a summary report of the best paths found in the search to use for demodulation element reassignment. This reduces the searching process related workload of the microprocessor and also reduces the modem costs by allowing a complete channel element modem circuit to be produced in a single IC.
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公开(公告)号：DE60027270T2
公开(公告)日：2007-04-12
申请号：DE60027270
申请日：2000-02-08
Applicant: QUALCOMM INC
Inventor： LEVIN A , RIDDLE C , SHERMAN TOM
IPC: H04B1/7085
Abstract: In order to time track an incoming signal, a receiver demodulates a first instance of a signal to produce a first set of energy values corresponding to a set of possible data values of the signal. The receiver also demodulates a second instance of the signal to produce a second set of energy values corresponding to the set of possible data values. The receiver combines the first and the second sets of energy values to determine a combined set of energy values. The receiver determines a first estimate of a most likely transmitted data value based upon the combined set of energy values. The receiver decovers an early set of despread samples of the first instance using a symbol corresponding to the first estimate to produce a first early energy value. The receiver decovers a late set of despread samples of the first instance using the symbol corresponding to the first estimate to produce a first late energy value. Finally, the receiver determines a time offset of the first instance based upon the first early and the first late energy values.
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公开(公告)号：DE69533665D1
公开(公告)日：2004-11-25
申请号：DE69533665
申请日：1995-07-05
Applicant: QUALCOMM INC
Inventor： TIEDEMANN G , GILHOUSEN S , ODENWALDER P , ZEHAVI EPHRAIM , LEVIN A , WHEATLEY E
Abstract: A method and apparatus for controlling transmission power in a variable rate communication system is disclosed. The method disclosed provides for a closed loop power control method. A first remote station controls the transmission power of a second remote station by transmitting a rate dependent power control signal to the second remote communication station. Since only the second communication knows its transmission rate a priori, it must determine its course of action in accordance with both the received power control signal and the knowledge of its transmission rate.
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