摘要:
Superimposing phantom-mode signals reinforces existing differentially driven DSL downstream signals in a vectored binder of DSLs or reinforces upstream vectored signals in a binder of differentially excited twisted pairs, thus expanding the extra transmission modes of the previous GDSL multi-wire two-sided-excitation invention to the case where coordination can only occur on one-side of the binder. Each pair is treated as a common-mode antenna with respect to earth ground, with some pairs selectively excited at the transformer center tap at the transmit end with respect to a common (earth or chassis) ground reference. Corresponding receivers on other non-excited pairs sense the signals between their center taps and a ground at the opposite ends of the lines to the exciting transmitters. A dual use with hybrid circuits allows the receiving circuit to also have an upstream transmitter and an upstream-sensing receiver on the center tap of the opposite side of an adjacent wire.
摘要:
Control of a digital communication system having a plurality of communication lines on which signals are transmitted and received is implemented using a variety of methods and systems. According to one embodiment of the present invention, a method is implemented where the signals are affected by interference during transmission and each of the communication lines has at least one transmitter and at least one receiver. A model is created of the interference characteristics due to the signals carried on the communication lines. Interference characteristics for a line are determined based on the model and actual signals carried on other communication lines different from the line for which the characteristics are being determined. Actual interference is compensated for on the communication line using the determined interference characteristics.
摘要:
Methods, techniques and apparatus identify members and characteristics of binders and/or other groups of communication lines such as those in a DSL system. Information obtained includes the identification (for example, by scanning) of significant crosstalking “offenders” and their “victims” that are affected by the crosstalk. One or a small number of modems are instructed to transmit with preselected transmit spectra, after which evidence of crosstalk in the noise spectrum data is examined for potential victim lines. Direct evidence of noise spectrum contribution by a suspected offender line may be obtained by collecting reported noise spectrum data and/or estimated noise spectrum data from potential victim lines. Also, where such direct evidence is not available, or in addition to it, other operational data showing crosstalk interference relating to potential victim lines can be used. The transmitting modem can either be on the CO/RT side or on the CPE side. Modems other than suspected offenders might transmit zero or minimal power in one or more selected frequency bands during scanning to reduce the risk that a modem and/or line not being examined for “offender” status supplies unnecessarily complicating and/or dominant crosstalk during the procedure. For DMT modulated DSL transceivers, well designed transmit spectra can be easily enforced by manipulating line profiles where such well designed line profiles cause minimal or no interruption to existing DSL customers. The invention also can be used to identify (partially or fully) the absolute values of crosstalk channels making up a channel transfer function.
摘要:
Information is sent by a DSL system component using a non-disruptive operational data parameter. One or more bits of the non-disruptive operational data parameter are used to send other information. In some instances the selected parameter will be an unused parameter, such as an unused fast operational mode or interleaved operational mode parameter used to report operational data in a DSL system. In one embodiment of the invention, a remote modem provides a unique equipment identifier that can be paired with the telephone number on which the modem is operating. Verification of and/or searching for the correct pairing of telephone number and unique equipment identifier can be performed as well.
摘要:
A self-learning and/or self-adjusting communication controller and/or optimizer uses operational data collected from a communication system to adjust operation of the communication system to changing operational, environmental, etc. conditions and, in some embodiments, to customize operation of the communication system's lines and components so that their performance can be controlled, improved and/or optimized. In various embodiments, operational parameters and/or rules are established and/or adjusted based on information obtained from the system concerning the system's operation; information regarding margins used by a DSL system and code violation counts reported by the DSL system are used to set margin levels for one or more line sets (each line set including an individual line, a group of lines, a binder, etc.) and/or other users and/or components of the DSL system; and, the controller and/or optimizer forces a small number of test lines into as yet un-experienced and/or unimplemented operational conditions so that new knowledge can be obtained.
摘要:
Adaptive FEC coding is used to adjust the codeword composition of FEC codewords in a communication system. A codeword composition ratio may be adjusted in response to variance of a measured transmission error value from a target transmission error value in the system. The codeword composition ratio may be any quantity or value that represents the relation between the payload and parity bytes in the applicable FEC coding scheme. Adjustment of the codeword composition ratio may be adjusting parameters such as the N, K and/or R values in ADSL1 systems or the INP and/or maximum interleaving delay values in ADSL2 systems. A controller may be used to monitor, analyze and adjust the various values used in adaptively managing FEC coding. The present invention may be implemented in a transmission system in which a transmitter transmits data to a receiver via a transmission channel, such as a DSL system.
摘要:
A high speed multiple user multiple-loop DSL system is described. In one embodiment, it includes a first DSL loop to carry DSL traffic to a first user and a second DSL loop to carry DSL traffic to a second user. A first junction connects the traffic of the first DSL loop to a third DSL loop, and a second junction connects the traffic of the second DSL loop to the third DSL loop.
摘要:
Improved DSL and/or other communication system services can be provided by motivating users, service providers and operators to implement and comply with one or more operational conditions, such as parameter value limits and/or ranges, that enhance operation of the communication system. Enhanced operation can include providing a reward such as an operational benefit to one or more users and/or mitigating problems experienced by other users in the communication system, which can be one or more communication lines. A DSL line implementing and complying with one or more operational conditions is provided with a reward (such as an operational benefit like a higher maximum data rate), which is otherwise withheld if the line fails to comply with the condition(s). Each operational condition may be set and monitored by a controller, such as a DSL optimizer that collects and analyzes operational data to determine compliance. Other requirements may be imposed for a DSL line to be eligible for the reward, such as the requiring the DSL line to provide operational data to the controller and requiring the DSL line's acceptance of control signals from the controller. The controller can use the operational data and line control to enhance system operation, for example to reduce crosstalk between lines in a common binder.
摘要:
An apparatus comprises at least one vectoring engine and a cross-connect coupled to the vectoring engine. The cross-connect is to couple with each of a plurality of customer premises equipment (CPE) devices via a respective DSL loop. An interface is to receive instructions for the cross-connect to couple the vectoring engine to a nonoverlapping subset of the CPE devices via the respective DSL loops. The interface is further to receive instructions for the vectoring engine to apply vectoring to the DSL loop via which to couple one of the CPE devices to the cross-connect.
摘要:
A variety of bi-directional data transmission systems that facilitate communications between a plurality of remote units (15) and a central unit (10) using a frame based discrete multi-carrier transmission scheme are disclosed. In each of the systems, frames transmitted from the plurality of remote units (15) are synchronized at the central unit (10). A variety of novel modem arrangements and methods for coordinating communications between a plurality of remote units (15) and a central unit (10) to facilitate multi-point-to-point transmission are disclosed. The invention has application in a wide variety of data transmission schemes including Asymmetric Digital Subscriber Line systems that includes the transmission of signals over twisted pair, fiber and/or hybrid telephone lines, cable systems that includes the transmission of signals over a coaxial cable, and digital cellular television systems that include the transmission of radio signals.