公开(公告)号：WO1995015630A1

公开(公告)日：1995-06-08

申请号：PCT/US1994012855

申请日：1994-11-08

Applicant: INTEGRATED NETWORK CORPORATION

Inventor： INTEGRATED NETWORK CORPORATION ,  EMERSON, Earl, A. ,  GONZALES, Henry, J. ,  HONG, Kyung-Yeop

IPC: H04L01/24

CPC classification number: H04L1/247 ,  G06F11/1402 ,  G06F11/22 ,  G06F13/38 ,  H04B17/401 ,  H04L1/241 ,  H04L1/243 ,  H04L1/244 ,  H04L43/50

Abstract: A system for isolating the direction of communication errors in the local loop of a digital data network is described. A Network Interface Unit (NIU) located at the customer premises typically has a loopback feature, allowing for Bit Error Rate Tests (BERT) to be performed on the local loop from a remote test system located on the data network. The NIU loopback test isolates transmission problems at the customer premises from problems on the local loop. The present invention adds test pattern generation capability to the NIU, allowing the remote test system to determine whether the transmission problem on the local loop is in the network to customer premises direction or in the customer premises to network direction.

Abstract translation: 描述了用于隔离数字数据网络的本地环路中的通信错误的方向的系统。 位于客户驻地的网络接口单元（NIU）通常具有环回功能，允许在位于数据网络上的远程测试系统的本地环路上执行误码率测试（BERT）。 NIU环回测试将客户端的传输问题与本地环路上的问题隔离开来。 本发明向NIU添加测试模式生成能力，允许远程测试系统确定本地环路上的传输问题是否在网络中到客户驻地方向或者在客户驻地到网络方向。

公开(公告)号：WO2015054297A1

公开(公告)日：2015-04-16

申请号：PCT/US2014/059548

申请日：2014-10-07

Applicant: QUALCOMM INCORPORATED

Inventor： WILEY, George Alan ,  LEE, Chulkyu

IPC: H04L1/24 ,  H04L1/20

CPC classification number: H04L7/042 ,  H04L1/205 ,  H04L1/206 ,  H04L1/247 ,  H04L5/20 ,  H04L25/0272 ,  H04L25/0282 ,  H04L25/0294 ,  H04L25/0298 ,  H04L25/4917

Abstract: System, methods and apparatus are described that facilitate tests and measurements related to multi-wire, multi-phase communications links. Information is transmitted in N-phase polarity encoded symbols and an eye pattern corresponding to the symbols is generated such that the symbols are aligned with a trigger for each symbol that corresponds to a clock edge used to sample the symbols. The eye pattern may be used to determine sufficiency of setup times in the communication links and other such characteristics defining a communications channel capabilities.

Abstract translation: 描述了便于与多线，多相通信链路相关的测试和测量的系统，方法和装置。 信息以N相极性编码的符号发送，并且生成与符号相对应的眼图，使得符号与对应于用于采样符号的时钟边缘的每个符号的触发对齐。 眼图可以用于确定通信链路中的建立时间的充分性以及定义通信信道能力的其它这样的特性。

公开(公告)号：WO98036545A1

公开(公告)日：1998-08-20

申请号：PCT/US1998/001029

申请日：1998-01-20

IPC: H04L1/24 ,  H04L25/02 ,  H04L27/152 ,  H04L27/14

CPC classification number: H04L25/0262 ,  H04L1/247 ,  H04L27/1525

Abstract: A receiver (100) is used for processing a multi-level FSK signal, comprising a converter (101) for converting the multi-level FSK signal into a sequence of state transitions, and a baud rate detector (111). The baud rate detector (111) comprises in a plurality of sampling intervals, wherein each of the plurality of sampling intervals is offset by a first predetermined time from other sampling intervals, and wherein each of the plurality of sampling intervals is further subdivided into a plurality of recording intervals, a plurality of counters (502-508) for counting the sequence of state transitions that occur during at least a minimum number of the plurality of recording intervals. The baud rate detector (111) further comprises a baud rate detection circuit (524) for detecting the desired baud rate based on counts recorded in a memory (522).

Abstract translation: 接收器（100）用于处理多级FSK信号，包括用于将多级FSK信号转换成状态转换序列的转换器（101）和波特率检测器（111）。 波特率检测器（111）包括多个采样间隔，其中多个采样间隔中的每一个从其他采样间隔偏移第一预定时间，并且其中多个采样间隔中的每一个被进一步细分为多个 多个计数器（502-508），用于计数在所述多个记录间隔的至少最小数目期间发生的状态转换序列。 波特率检测器（111）还包括用于基于记录在存储器（522）中的计数来检测所需波特率的波特率检测电路（524）。

公开(公告)号：WO1990004295A1

公开(公告)日：1990-04-19

申请号：PCT/US1989004503

申请日：1989-10-12

Applicant: CONCORD COMMUNICATIONS, INC.

Inventor： CONCORD COMMUNICATIONS, INC. ,  FURLONG, Darrell

IPC: H04L01/24

CPC classification number: H04L25/06 ,  H04L1/247

Abstract: A symbol detection and correction scheme for local area network modems, especially those which receive one of three symbols at any given time, such as those operating in accordance with the IEEE 802.4 standard. The invention significantly improves the bit error rate observed by the layer above the modem. The modem operates on a received signal with a pair of slicers. One slicer operating as a two-symbol decoder, and a second slicer operates as a three-symbol decoder. A receiver state machine is used to keep track of which portion of a frame is currently expected to be received. Depending upon the particular context, one or both of the slicer outputs are used by the state machine to determine which of the three symbols was received. For example, when the receiver is in a state where only one of two data symbols are expected, and no control symbols are expected, only the two-symbol slicer output is used. The three-symbol slicer output, and logical combinations of the three-symbol slicer output and the two-symbol slicer output, are used at other times. The receiver state machine recognizes errors in pseudo-silence, start delimiter, and end-delimiter sequences without reporting such errors to the upper level, thereby greatly decreasing the error rate observed there.