Arrangement for wideband transmission via a switched network
AssigneeAT&T Bell Laboratories
InventorPeter D. Nash
Life of this patent
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Abstract
A plurality of narrow-band channels are established via a switched network between end terminals to provide a wideband facility. Wideband messages are divided into a plurality of narrow-band signals each of which is transmitted over a corresponding narrow-band channel. A data recovery unit connected to one of the network switching offices measures the relative delay between channels and inserts a compensating delay so that the portions of a wideband message transmitted in the same time frame from one end terminal arrive at the other end terminal in a single time frame.
Claims8
For use in a communications network having a plurality of switching offices, customer wideband terminals, and time division multiplex (TDM) channels having a relatively narrow bandwidth for interconnecting said terminals via said offices, a method for establishing to a designated one of said terminals a facility having a wider bandwidth than any one of said TDM channels comprising the steps of:
- establishing to said designated terminal a selected plurality of said TDM channels whose combined bandwidth is at least equal to the bandwidth required by said designated terminal,
- transmitting from one end over each said selected TDM channel a test pattern of data in successive time frames,
- measuring the relative delay between selected TDM channels by comparing at the other end of said selected channels during a particular time frame the data received on each one of said selected TDM channels with the data received on another one of said selected TDM channels, and
- selectively inserting delay in the transmission of data over any of said selected TDM channels so that data transmitted in a single time frame from one end over all said selected TDM channels will be received at the other end of all said selected TDM channels in a single time frame.
For use in a communications network having a plurality of customer stations, a plurality of switching offices, a plurality of time-division multiplex channels each having relatively narrow-band transmit and receive paths, and a data recovery unit coupled to one of said offices, apparatus for establishing a transmission facility between wideband terminals at a calling and called one of said stations wherein said facility has a bandwidth greater than the individual ones of said channels, said apparatus comprising:
- means at said data recovery unit responsive to a service request from said calling station for connecting a plurality of said channels to the wideband terminals at said calling and called stations,
- means effective upon the connection of said channels for causing said terminals to interconnect via a loop-back the associated transmit and receive paths,
- means for transmitting test data from said data recovery unit over the transmit paths associated with each said connected channel,
- means at said data recovery unit responsive to the receipt of said test data over the receive paths of said connected channels for comparing during one time frame the test data received on each said channel with the test data received on all other said connected channels, and
- means responsive to said comparing means and effective when test data on a first of said connected channels arrives at said data recovery unit in a time frame subsequent to the time frame during which said test data arrives over another of said connected channels for inserting delay in the transmission of subsequent data over said other channel.
Dependencies are inferred from the claim text.