公开(公告)号：WO1993007688A1

公开(公告)日：1993-04-15

申请号：PCT/US1992006767

申请日：1992-08-14

Applicant: MOTOROLA, INC.

Inventor： MOTOROLA, INC. ,  BORTH, David, E. ,  MUELLER, Bruce, D. ,  BAUM, Kevin, L.

IPC: H04B15/00

CPC classification number: H04L27/22 ,  H04L25/03197 ,  H04L25/03203 ,  H04L2025/03401

Abstract: A Viterbi equalizer (366) for decoding a π/4 DQPSK modulated signal. Because symbol values of adjacent symbols of a π/4 DQPSK signal are offset in phase relative to one another, allowable values of succeeding states of a π/4 DQPSK signal are four in number. The signal paths of the Viterbi equalizer are thereby limited in number to four allowable next-states (600) and the Viterbi equalizer (366) is operative to select certain ones of the paths connecting the states at the adjacent time intervals as survivor paths to form maximum likelihood paths thereby.

公开(公告)号：WO1997020407A1

公开(公告)日：1997-06-05

申请号：PCT/US1996003630

申请日：1996-03-08

Applicant: MOTOROLA INC.

Inventor： MOTOROLA INC. ,  CORRIGAN, Richard, James ,  MUELLER, Bruce, D. ,  BURKE, Timothy, Mark

IPC: H04J03/12

CPC classification number: H04J3/0682 ,  H04J3/1694 ,  H04N7/17309

Abstract: A method and apparatus for accessing a communications system (100) in which a cable control unit (102) is connected to subscribers (104) by a distribution network (106) and a combiner (108). The CCU (102) located at the cable company headend sends and receives telephone calls to and from the home subscribers (104), and includes cable port transceivers (112) which are connected to the combiner (108). The CPX (112) generates downstream carrier channels in the communications system (100). The transmissions from CCU (102) in the distribution network (106) are facilitated by downstream fiber trunks (120) and upstream fiber trunks (122). The fiber trunks are fiber optic cables and are connected to fiber nodes (124). Each fiber node (124) has a connection to at least one serving area (126). The serving area (126) includes coaxial cable, trunk amplifiers (128) and bi-directional line extenders (130). The CAU (134) provides telephone and television services at the subscriber premises (104).

Abstract translation: 一种用于访问通信系统（100）的方法和装置，其中电缆控制单元（102）通过分配网络（106）和组合器（108）连接到订户（104）。 位于电缆公司头端的CCU（102）向家庭用户（104）发送和接收电话呼叫，并且包括连接到组合器（108）的电缆端口收发器（112）。 CPX（112）在通信系统（100）中生成下行载波信道。 来自分配网络（106）中的CCU（102）的传输由下游光纤干线（120）和上行光纤干线（122）促成。 光纤干线是光纤电缆，并连接到光纤节点（124）。 每个光纤节点（124）具有至少一个服务区域（126）的连接。 服务区域（126）包括同轴电缆，中继放大器（128）和双向线路扩展器（130）。 CAU（134）在用户住宅（104）提供电话和电视服务。

公开(公告)号：WO1993007701A1

公开(公告)日：1993-04-15

申请号：PCT/US1992006766

申请日：1992-08-14

Applicant: MOTOROLA, INC.

Inventor： MOTOROLA, INC. ,  BAUM, Kevin, L. ,  MUELLER, Bruce, D.

IPC: H04L27/22

CPC classification number: H04L27/2332 ,  H04L7/041 ,  H04L27/2278

Abstract: A system and method for determining an absolute phase value of a differentially-encoded, DQPSK signal. A stored set of sequences of ID sequence (92) is compared with a received ID-sequence (88) of a differentially-encoded, DQPSK signal transmitted to the receiver. The stored (92) and the received ID sequences (88) are correlated, and the stored values of the ID sequence (92) are adjusted by the value of the calculated correlation.

公开(公告)号：WO1994002991A1

公开(公告)日：1994-02-03

申请号：PCT/US1993005730

申请日：1993-06-18

Applicant: MOTOROLA INC.

Inventor： MOTOROLA INC. ,  BAUM, Kevin, L. ,  MUELLER, Bruce, D.

IPC: H03H07/30

CPC classification number: H03H21/0012 ,  H04B1/1081 ,  H04B7/005 ,  H04L25/0212 ,  H04L25/025

Abstract: The process of the present invention computes the update (403) to the least mean square channel estimator taps. The update coefficient for each tap is computed independently based on the power of each tap (402) relative to the main tap power.

Abstract translation: 本发明的过程计算到最小均方通道估计器抽头的更新（403）。 基于每个抽头（402）相对于主抽头功率的功率，独立地计算每个抽头的更新系数。

公开(公告)号：WO1993008637A1

公开(公告)日：1993-04-29

申请号：PCT/US1992006765

申请日：1992-08-14

Applicant: MOTOROLA, INC.

Inventor： MOTOROLA, INC. ,  MUELLER, Bruce, D. ,  BORTH, David, E. ,  BAUM, Kevin, L.

IPC: H03D01/00

CPC classification number: H04L25/03197 ,  H04L27/22 ,  H04L2025/03401

Abstract: A system and method for calculating survivor metrics in a Viterbi equalizer (424) of a receiver (56), such as a receiver operative to receive a PSK-modulated signal, for example, a π/4, differential, phase-shift-keying, modulated signal. The state transition metric, defined as a function of two successive states, is converted into a function defined by pairwise differences between allowable symbols of the PSK-modulated signal. When operative to receive π/4 DQPSK-modulated signal, the number of calculations required to calculate state transition metrics is reduced significantly.

公开(公告)号：WO1997020430A1

公开(公告)日：1997-06-05

申请号：PCT/US1996017571

申请日：1996-11-01

Applicant: MOTOROLA INC.

Inventor： MOTOROLA INC. ,  CORRIGAN, Richard, James ,  MUELLER, Bruce, D. ,  BURKE, Timothy, M.

IPC: H04N07/10

CPC classification number: H04H20/12 ,  H04H20/78 ,  H04H60/94 ,  H04H60/97 ,  H04L7/04 ,  H04L12/2801 ,  H04N7/17309

Abstract: A method and apparatus in a communications system (100) for providing communications units (134) access therein in which the communications system (100) includes a cable distribution network (106) with a base communications unit (102) and a number of downstream communications units (134) all connected thereto. A plurality of channels are used to transmit data between the base communications unit (102) and the downstream communications units (134). A first set of channels are used primarily for access in the communications system (100) and a second set of channels are used for transmitting data within the communications system (100) after access has been gained. A mechanism is provided for handling collisions in transmissions between the downstream communications units (134) to the base communications unit (102) in attempting to gain access to the communications system (100).

Abstract translation: 一种用于在其中提供通信单元（134）访问的通信系统（100）中的方法和装置，其中所述通信系统（100）包括具有基站通信单元（102）的电缆分配网络（106）和多个下行通信 单元（134）全部连接到其上。 多个信道用于在基本通信单元（102）和下游通信单元（134）之间传送数据。 第一组信道主要用于通信系统（100）中的接入，并且第二组信道用于在获取接入之后在通信系统（100）内发送数据。 提供了一种机制，用于在尝试访问通信系统（100）时，处理下游通信单元（134）与基站通信单元（102）之间的传输中的冲突。

公开(公告)号：WO1993001673A1

公开(公告)日：1993-01-21

申请号：PCT/US1992003757

申请日：1992-05-07

Applicant: MOTOROLA, INC.

Inventor： MOTOROLA, INC. ,  MUELLER, Bruce, D. ,  BAUM, Kevin, L. ,  BORTH, David, E. ,  RASKY, Phillip, D. ,  WINTER, Eric, H.

IPC: H04L27/06

CPC classification number: H04L27/22 ,  H04B7/0845 ,  H04L25/067

Abstract: A system and method for correcting for Rayleigh interference of a signal tansmitted upon a multi-path channel. The system adaptively calculates values of channel gain and noise variance (178) of the channel upon which the signal is transmitted, and generates signals (182, 186) indicative of such calculations which are supplied to a decoder (188). The system may be utilized to form a portion of a coherent, or noncoherent receiver which receives encoded and differentially-encoded signals.

公开(公告)号：WO1993000747A1

公开(公告)日：1993-01-07

申请号：PCT/US1992003763

申请日：1992-05-08

Applicant: MOTOROLA, INC.

Inventor： MOTOROLA, INC. ,  BAUM, Kevin, L. ,  MUELLER, Bruce, D.

IPC: H03L07/00

CPC classification number: H03H21/0043 ,  H03J7/04

Abstract: The process of the present invention generates an optimum automatic frequence control signal in an apparatus that has a plurality of adaptive algorithms, each adaptive algorithm having a reference signal with an associated frequency dither. The process starts by comparing the performance of each of the plurality of adaptive algorithms. This difference is input to a comparator (6) where it is compared to zero. This delta signal then modifies the numerically controlled oscillator frequency (8). After several iterations, the frequency offset is reduced to substantially zero.