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    METHOD FOR APPLYING PREDISTORTION TO INPUT SIGNAL AND PREDISTORTION SYSTEM
    1.
    发明专利
    METHOD FOR APPLYING PREDISTORTION TO INPUT SIGNAL AND PREDISTORTION SYSTEM 审中-公开

    公开(公告)号：JP2003124752A

    公开(公告)日：2003-04-25

    申请号：JP2002222279

    申请日：2002-07-31

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GIARDINA CHARLES ROBERT ,  KIM JAEHYEONG ,  LAI HAOBO

    IPC: H03F1/32

    Abstract: PROBLEM TO BE SOLVED: To provide a system and a method for applying predistortion to an input signal in order to remove the predistortion of an output signal. SOLUTION: In the predictive system and method to use an outer predistortion function for controlling a signal to be inputted to an inner predistortion function in order to control a signal to be inputted to a distortion generating circuit, the inner predistortion function reduces the distortion from the distortion generating circuit and the remaining distortion is reduced by the outer predistortion function. The inner predistortion function is determined by using the output of that function and the output of an amplifier. The outer predistortion function is determined by using output to that function and output to the inner predistortion function. Thus, a signal on a signal path is predistorted within a plurality of stages prior to amplification, predistortion caused by the amplification of the signal is canceled, and in an amplified signal obtained as a result, distortion is reduced.

    INFORMATION TRANSMITTING METHOD
    2.
    发明专利
    INFORMATION TRANSMITTING METHOD 失效

    公开(公告)号：JP2000341249A

    公开(公告)日：2000-12-08

    申请号：JP2000117077

    申请日：2000-04-18

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GIARDINA CHARLES ROBERT ,  RUDRAPATNA ASHOK N

    IPC: H04K3/00 ,  H04J11/00 ,  H04J13/00 ,  H04J13/12 ,  H04J13/04

    Abstract: PROBLEM TO BE SOLVED: To make it possible to use a semi-Walsh function system which has high repulsion to wiretapping and jamming and enables multiple access and acquisition by transmitting a 1st information set of a user over a communication channel by using a 1st code and transmitting a 2nd information set of the user over the communication channel by using a 2nd code instead of the 1st code. SOLUTION: A diagonal matrix Dk is multiplied from back of a Walsh Hadmard matrix H to obtain the semi-Walsh function system Qk=HDk. An (i)th row is assigned to an (i)th user to enable multiple access over a data channel. Further, the diagonal matrix Dk is obtained each time information bit is sent by using a pseudo-random number generator, so the possibility that this row comes from semi-Walsh system Qk different for every transmit information bit is very high and it seems for an observer who does not know a formula for equal-length conversion that a semi-Walsh function column obtained as a result is random, so wiretapping is difficult.

    5.
    发明专利
    未知

    公开(公告)号：BR0001581A

    公开(公告)日：2000-12-19

    申请号：BR0001581

    申请日：2000-04-11

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： GIARDINA CHARLES ROBERT ,  RUDRAPATNA ASHOK N

    IPC: H04K3/00 ,  H04J11/00 ,  H04J13/00 ,  H04J13/12

    Abstract: The method enhances security for transmission of information by utilizing systems of Quasi-Walsh functions to provide a high resilience against jamming and interception and in addition allows multiple access and acquisition.It switches among generalized systems of Quasi-Walsh functions at some rate r, where r may be either a fixed or a variable value not equal to zero. An independent claim describes a method of transmitting bits for an ith user.

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