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    SPACE-TIME PROCESSING FOR WIRELESS SYSTEMS WITH MULTIPLE TRANSMIT AND RECEIVE ANTENNAS
    21.
    发明专利
    SPACE-TIME PROCESSING FOR WIRELESS SYSTEMS WITH MULTIPLE TRANSMIT AND RECEIVE ANTENNAS 未知

    公开(公告)号：CA2350878C

    公开(公告)日：2005-01-04

    申请号：CA2350878

    申请日：2001-06-19

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： RASHID-FARROKHI FARROKH ,  LOZANO ANGEL ,  VALENZUELA REINALDO A

    IPC: H04J3/00 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08 ,  H04B1/74 ,  H04B7/005

    Abstract: Signals are developed for use in a wireless system with multiple transmit a nd multiple receive antennas so that even in the face of some correlation the most open-loop capacity that can be achieved using a substantially open-loop system with a channel of that level of correlation is obtained. In accordance with the principles of the invention, the signals transmitted from the various antennas are processed so as to improve their ability to convey the maximum amount of information. More specifically, the data to be transmitted is divided into M+1 substreams, where M is the number of transmi t antennas. Each transmit antenna is supplied with a combination signal that is made up of a weighted version of a common one of the substreams and a weighted version of a respective one of the substreams that is supplied uniquely for that antenna, so that there are M transmit signals. A receiver having N antennas receives the M transmit signals as combined by the channel and reconstitutes the original data therefrom. This may be achieved using successive decoding techniques. Advantageously, the capacity, i.e., the rate of information that can be conveyed with an arbitrarily small probabili ty of error when the instantaneous forward channel condition is unknown to the transmitter, is maximized.

    22.
    发明专利
    未知

    公开(公告)号：DE60104252D1

    公开(公告)日：2004-08-19

    申请号：DE60104252

    申请日：2001-03-05

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： LOZANO ANGEL ,  RASHID-FARROKH FARROKHI ,  VALENZUELA REINALDO A

    IPC: H04J3/00 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08

    Abstract: Signals are developed for use in a wireless system with multiple transmit and multiple receive antennas so that even in the face of some correlation the most open-loop capacity that can be achieved using a substantially open-loop system with a channel of. that level of correlation is obtained. In accordance with the principles of the invention, the signals transmitted from the various antennas are processed so as to improve their ability to convey the maximum amount of information. More specifically, the data to be transmitted is divided into M+1 substreams, where M is the number of transmit antennas. Each transmit antenna is supplied with a combination signal that is made up of a weighted version of a common one of the substreams and a weighted version of a respective one of the substreams that is supplied uniquely for that antenna, so that there are M transmit signals. A receiver having N antennas receives the M transmit signals as combined by the channel and reconstitutes the original data therefrom. This may be achieved using successive decoding techniques. Advantageously, the capacity, i.e., the rate of information that can be conveyed with an arbitrarily small probability of error when the instantaneous forward channel condition is unknown to the transmitter, is maximized.

    POWER CONTROL AND CELL SITE LOCATION TECHNIQUE FOR CDMA SYSTEMS WITH HIERARCHICAL ARCHITECTURE
    23.
    发明专利
    POWER CONTROL AND CELL SITE LOCATION TECHNIQUE FOR CDMA SYSTEMS WITH HIERARCHICAL ARCHITECTURE 未知

    公开(公告)号：CA2308902C

    公开(公告)日：2003-12-02

    申请号：CA2308902

    申请日：2000-05-19

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： HUANG HOWARD C ,  KRISHNAMOORTHY RAJEEV ,  GITLIN RICHARD DENNIS ,  VALENZUELA REINALDO A

    IPC: H04B7/005 ,  H04W16/06 ,  H04W16/32 ,  H04W52/34 ,  H04Q7/36

    Abstract: Multiple microcell base stations are located within a macrocell having a single macrocell base station in an hierarchical architecture, and microcell users (.mu.-users) and macrocell users (M-users) communicate respectively with the .mu.-base and the M-base using the same frequency band, by appropriately (a) selecting the ratio of the radius r of each .mu. cell and the average distance d from the M-base (r and d are measured by the "radio distance", which includes the effects of shadowing), and (b) controlling the power level with which uplink (mobile to base) and downlink (base to mobile) messages are communicated. Typically, .mu.-cell size and location are chosen such that d/r > 10. With respect to uplink communications, the transmit powers of the .mu. -users in a .mu.-cell are controlled so that the total received power at the nearest M-base is equivalent to the received power from C M-users, where C is usually set to unity. As a result, the M-cell basically loses C users worth of capacity, but the total number of users is increased by virtue of the additional .mu.-users. With respect to downlink communications, as long as the microbase and the macrobase are coordinated systems, the .mu.-base transmit power is controlled so that at the point of handoff between a .mu.-base and M-base,the received power at a user from the two bases is equivalent, and the received power at the bases from this user is also equivalent. With this arrangement, the .mu.-base transmit power is increased as r grows and d decreases in order for this balance to occur. Where the M-base and .mu.-base have no knowledge of each other and handoffs are not allowed between the two base types, a family of I/Q short codes which are quasi-orthogonal to the existing short (pilot) codes are generated, and these codes are used to distinguish between the M-base and .mu.-base signals.

    POWER CONTROL AND CELL SITE LOCATION TECHNIQUE FOR CDMA SYSTEMS WITH HIERARCHICAL ARCHITECTURE
    26.
    发明专利
    POWER CONTROL AND CELL SITE LOCATION TECHNIQUE FOR CDMA SYSTEMS WITH HIERARCHICAL ARCHITECTURE 未知

    公开(公告)号：CA2308902A1

    公开(公告)日：2000-11-28

    申请号：CA2308902

    申请日：2000-05-19

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： KRISHNAMOORTHY RAJEEV ,  VALENZUELA REINALDO A ,  GITLIN RICHARD DENNIS ,  HUANG HOWARD C

    IPC: H04B7/005 ,  H04W16/06 ,  H04W16/32 ,  H04W52/34 ,  H04Q7/36

    Abstract: Multiple microcell base stations are located within a macrocell having a single macrocell base station in an hierarchical architecture, and microcell users (.mu.-users) and macrocell users (M-users) communicate respectively with the .mu.-base and the M-base using the same frequency band, by appropriately (a) selecting the ratio of the radius r of each .mu. cell and the average distance d from the M-base (r and d are measured by the "radio distance", which includes the effects of shadowing), and (b) controlling the power level with which uplink (mobile to base) and downlink (base to mobile) messages are communicated. Typically, .mu.-cell size and location are chosen such that d/r > 10. With respect to uplink communications, the transmit powers of the .mu. -users in a .mu.-cell are controlled so that the total received power at the nearest M-base is equivalent to the received power from C M-users, where C is usually set to unity. As a result, the M-cell basically loses C users worth of capacity, but the total number of users is increased by virtue of the additional .mu.-users. With respect to downlink communications, as long as the microbase and the macrobase are coordinated systems, the .mu.-base transmit power is controlled so that at the point of handoff between a .mu.-base and M-base, the received power at a user from the two bases is equivalent, and the received power at the bases from this user is also equivalent. With this arrangement, the .mu.-base transmit power is increased as r grows and d decreases in order for this balance to occur. Where the M-base and .mu.-base have no knowledge of each other and handoffs are not allowed between the two base types, a family of I/Q short codes which are quasi-orthogonal to the existing short (pilot) codes are generated, and these codes are used to distinguish between the M-base and .mu.-base signals.

    29.
    发明专利
    未知

    公开(公告)号：DE60039099D1

    公开(公告)日：2008-07-17

    申请号：DE60039099

    申请日：2000-12-12

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： FOSCHINI GERARD JOSEPH ,  LOZANO ANGEL ,  RASHID-FARROKHI FARROKH ,  VALENZUELA REINALDO A

    IPC: H04B7/06 ,  H04J3/00 ,  H04B1/04 ,  H04B1/10 ,  H04B1/18 ,  H04B7/08

    Abstract: In a MIMO system the signals transmitted from the various antennas are processed so as to improve the ability of the receiver to extract them from the received signal even in the face of some correlation. More specifically the number of bit streams that is transmitted simultaneously is adjusted, e.g., reduced, depending on the level of correlation, while multiple versions of each bit stream, variously weighted, are transmitted simultaneously. The variously weighted versions are combined to produced one combined weighted signal. The receiver processes the received signals in the same manner as it would have had all the signals reaching the receive antennas been uncorrelated. The weight vectors may be determined by the forward channel transmitter using the channel properties of the forward link which are made known to the transmitter of the forward link by being transmitted from the receiver of the forward link by the transmitter of the reverse link or the weight vectors may be determined by the forward channel transmitter using the channel properties of the forward link and the determined weight vectors are made known to the transmitter of the forward link by being transmitted from the receiver of the forward link by the transmitter of the reverse link. The channel properties used to determine the weight vectors may include the channel response from the transmitter to the receiver and the covariance matrix of noise and interference measured at the receiver.

    30.
    发明专利
    未知

    公开(公告)号：DE60104252T2

    公开(公告)日：2005-09-08

    申请号：DE60104252

    申请日：2001-03-05

    Applicant: LUCENT TECHNOLOGIES INC

    Inventor： LOZANO ANGEL ,  RASHID-FARROKH FARROKHI ,  VALENZUELA REINALDO A

    IPC: H04J3/00 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08

    Abstract: Signals are developed for use in a wireless system with multiple transmit and multiple receive antennas so that even in the face of some correlation the most open-loop capacity that can be achieved using a substantially open-loop system with a channel of. that level of correlation is obtained. In accordance with the principles of the invention, the signals transmitted from the various antennas are processed so as to improve their ability to convey the maximum amount of information. More specifically, the data to be transmitted is divided into M+1 substreams, where M is the number of transmit antennas. Each transmit antenna is supplied with a combination signal that is made up of a weighted version of a common one of the substreams and a weighted version of a respective one of the substreams that is supplied uniquely for that antenna, so that there are M transmit signals. A receiver having N antennas receives the M transmit signals as combined by the channel and reconstitutes the original data therefrom. This may be achieved using successive decoding techniques. Advantageously, the capacity, i.e., the rate of information that can be conveyed with an arbitrarily small probability of error when the instantaneous forward channel condition is unknown to the transmitter, is maximized.

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