A transceiver circuit for use in a high speed data transmission network is disclosed that provides for simultaneous bidirectional transmission of data over coaxial or twisted pair media. A transmitter circuit provides an output data signal to a bridge network. The bridge network develops a cancelling signal and a combined signal. A receiver section includes a high speed subtracting circuit that determines the difference between the cancelling signal and the combined signal to effectively cancel data supplied by the transmitter section.

Bidirectional transceiver for high speed data system

A data communication system is provided in which the data handling capacity of the system is doubled. The data in the system travels on a single wire in both directions simultaneously. Each pair of terminals associated with the communication system is interfaced with the single wire by a repeater. The repeater includes first and second directional couplers for coupling data signals from the repeater to the wire in the one direction and in the opposite direction, respectively, without substantial signal interference with signals being received by the repeater on the same wire. A wrap control function is included in the repeater which allows data signals to be placed on the wire going in the opposite direction from the received signals.

Bidirectional single wire data transmission and wrap control

A transceiver inserted between a signal source and a two-wire or one-wire line, designed to transmit balanced or unbalanced digital signals to a remote station at the opposite end of the line while receiving similar signals from the latter station, comprises a first and a second amplifier with inputs connected to the line at a proximal and a distal end of a line-terminating impedance, respectively. Each amplifier has an inverting output connected to a noninverting output of the other amplifier, the two nodes formed between the interconnected outputs being connected to respective inputs of a differential third amplifier feeding a signal receiver. The gain of the first amplifier is half that of the second amplifier whereby the locally generated signals are suppressed in the output of the third amplifier. The several amplifiers are realized in integrated circuitry and may be provided with switches for selective changeover between a balanced and an unbalanced mode of operation.

Transceiver for full-duplex transmission of digital signals over a common line

A duplex digital transmitter system is disclosed which permits simultaneous digital signal exchange over a two-wire loop. Two sets are provided at the ends of the loop, each having a three-port lattice adapted to separate the transmitted and received digital signals. The digital signals are encoded using a biphase scheme so that they have a zero D.C. component. Therefore the loop is used simultaneously to transmit D.C. power from one set to the other.

Duplex transmission mechanism for digital telephones

A transmitter/receiver interface (12) for use with a bi-directional transmission path (18) couples a transmitter (14) and a receiver (16) to the bi-directional transmission path (18). The transmitter/receiver interface (12) separates transmitted signals (20) and received signals (22) and routes them from the transmitter (14) and to the receiver (16) with negligible interference. The transmitter/receiver interface (12) incorporates coupling elements (44 and 50) that couple the transmitter to the transmission path and incorporates networks that couple the receiver to the transmission path. Impedances of the networks are derived based on the coupling elements and the transfer characteristics of the transmission path to provide consistent attenuation of the transmit signal over a large frequency range.

Transmitter/receiver interface apparatus and method for a bi-directional transmission path

A duplex digital signalling system includes a transmission line having characteristic impedance terminations, a transmitter at each end of the transmission line for supplying digital signals through the characteristic impedance termination to the transmission line, and a differential receiver at each end of the transmission line. A resistor network couples each receiver across the local characteristic impedance termination, so that each receiver responds only to the distant transmitter, and digital information may be simultaneously transmitted in both directions through the transmission line.

Davis William John

Papers

Simultaneous digital transmission in both directions over one line