Abstract: An apparatus and method are provided for generating a plurality of data frames in a DSL modem configured as an HTU-C device using a single clock source. The technique of the present invention generates a data clock signal by combining a first clock signal provided by a clock source and a receiver overhead signal provided by framing circuitry for indicating the insertion of frame overhead bits into a data frame. The generated data clock signal has the characteristics such that, while said receiver overhead signal is inactive, said data clock signal is active at a frequency substantially equal to frequency of the first clock signal, and while the receiver overhead signal is active, the data clock signal is inactive. The result of this technique is that incoming data is clocked into the data frame at a data rate substantially equal to the frequency of the first clock signal only during time intervals when frame overhead bits are not being inserted into the one data frame.

Abstract: A medium access contention protocol that is highly beneficial in wireless networks and particularly in wireless networks that employ a fixed minimum burst size such as OFDM wireless networks. In one embodiment, a MAC protocol is a demand-assigned protocol that maximizes utilization of the bus medium (the allocated frequency spectrum.) Each data communication device (DCD) in the network communicates with a central access point (AP). Multiple DCDs may request access from the AP in the same request access (RA) burst. Each of the multiple DCDs transmits its access request to the AP within a frequency domain channel in the RA burst that is orthogonal to the frequency domain channels used by the other DCDs requesting access. Each DCD includes channel training information in the access request burst to allow the AP and/or DCD to adapt to rapid variations in channel characteristics.

Abstract: Digitally compressed video/audio bit streams, when transmitted over digital communication channels such as digital subscriber loop (DSL) access networks, ATM networks, satellite, or wireless digital transmission facilities, can be corrupted due to lack of sufficient channel bandwidth. This invention describes schemes to ensure lossless transmission of bit streams containing pre-compressed video signals within the communication channels. The schemes herein comprises a rate conversion system that converts the bit rate of a pre-compressed video bit stream from one bit rate to another, and that is integrated with a digital communication channel, and a means to convey the maximum channel transmission rate to the rate conversion system to allow satisfactory transmission of the bit stream from the input of the rate converter through the transmission facility.

Abstract: A method and system for providing enhanced services for a network. The enhanced services use information about the network which is available to a subnet of communicating processors (such as a set of routers), collectively executing a common distributed technique for disseminating that network information. The router subnet collects network topology information and provides a service using that network topology information, responsive to requests from non-routers coupled to the network (such as a set of host processors). The router subnet also collects information advertised by hosts coupled to the network, and disseminates that host information to substantially all routers, using the common distributed technique for disseminating network topology information.

Abstract: A space-time signal processing system with advantageously reduced complexity. The system may take advantage of multiple transmitter antenna elements and/or multiple receiver antenna elements, or multiple polarizations of a single transmitter antenna element and/or single receiver antenna element. The system is not restricted to wireless contexts and may exploit any channel having multiple inputs or multiple outputs and certain other characteristics. Multi-path effects in a transmission medium cause a multiplicative increase in capacity.

Abstract: A cellular communication system hand-off protocol which helps minimize down time associated with a mobile device roaming among different cells in which different cells employ different communication channels (e.g., different frequency hopping sequences). In a preferred embodiment, each base station is configured to communicate its own particular hopping sequence to the host computer via the system backbone. Each base station then provides to mobile devices which are registered thereto information regarding the particular hopping sequences employed by other base stations servicing cells into which the mobile device may roam. Such information includes the particular hopping sequences together with an indication of what location in the sequence the base stations are currently at in any given time.

Abstract: A cellular communication system in which dedicated repeater controller transceivers are included in base stations and wireless base stations. The repeater controller transceivers are configured to operate on a different channel as compared to communications received by or transmitted directly from mobile terminals. By utilizing a dedicated channel for communications between the base stations and wireless base stations, the contention areas formed by overlapping cell areas is effectively eliminated. The different channels may be based on differences in parameters such as frequency and/or data encoding techniques.

Abstract: A correlation system for use in wireless direct sequence spread spectrum systems includes a RF down converter which receives an encoded RF signal and generates therefrom analog in-phase (I) and quadrature (Q) signal components. These components are digitized and the digitized signals are then passed to each of the high precision correlator circuit and a low precision correlator circuit. The low precision correlator circuit consist of a bank of a plurality of low precision correlators which receive the I and Q signal components as inputs and correlates the same with progressively phase shifted or delay pseudo noise (PN) codes. A low precision correlation circuit locks on to the appropriate PN code phase shift or delay and applies the same as a reference PN code to the high precision correlation circuit for data acquisition and demodulization.

Abstract: In accordance with the invention, a method and structure are provided for obtaining a ratio of M/(2.sup.N +K) by feeding various carry-out (and/or complemented carry-out) signals from full-adders back to various frequency control inputs of the full-adders to modify the denominator of the division ratio. By doing this, K additional or fewer counts are accumulated during each cycle. Thus, the denominator can be changed from 2.sup.N to 2.sup.N +K, where K can be either positive or negative to obtain the desired M/(2.sup.N +K) ratio.

Abstract: A cellular communication system in which dedicated repeater controller transceivers are included in base stations and wireless base stations. The repeater controller transceivers are configured to operate on a different channel as compared to communications received by or transmitted directly from mobile terminals. By utilizing a dedicated channel for communications between the base stations and wireless base stations, the contention areas formed by overlapping cell areas is effectively eliminated. The different channels may be based on differences in parameters using infrared communication techniques.

Abstract: For use in a communications network capable of establishing a bonded call between first and second endpoints using at least two bonded communication channels, a subsystem for preserving a relative latency of the at least two bonded communication channels to allow the bonded call to be transferred to a third endpoint. The subsystem includes: (1) a buffer depth index detection circuit that detects learned values of buffer depth indices associated with the bonded call and stored at a first location and (2) a buffer depth index transmission circuit, coupled to the buffer depth index detection circuit, that transmits the learned values to a second location accessible by the third endpoint to allow the bonded call to be transferred to the third endpoint without requiring the third endpoint to relearn the values.

Abstract: A point-to-multipoint or two-way communications system is provided by a nodal transmitter located in a node with a plurality of nodal antennas radiating different polarization signals about the node. The system includes subscriber stations with directional antennas adapted to receive signals radiated from the nodal transmitter. The system may additionally include capability for transmitting and radiating subscriber signals to the nodal transmitter location for two-way communications.

Abstract: A digital system for Bit Error Rate Testing (BERT) of test transmission lines and/or devices and including a test equipment coupled to at least one transmission line for transferring digital information between the test equipment and a company office, a bit error generator coupled to the transmission lines for generating test patterns, a device for storing a plurality of predetermined profiles, each profile having associated therewith at least one parameter for measuring the integrity of the test equipment or the transmission lines, the parameters including one of the generated test patterns.

Abstract: A communication network having a plurality of routers, each connected to a host system by a LAN network and interconnected by a switched network, the common network using a shared or common IP and MAC address in the routers forming a subnet. Host systems on the same subnet use the shared or common IP address as their default gateway address when accessing host systems on another subnet.

Abstract: The invention provides an enhanced datagram packet switched computer network. The invention processes network datagram packets in network devices as separate flows, based on the source-destination address pair in the datagram packet. As a result, the network can control and manage each flow of datagrams in a segregated fashion. The processing steps that can be specified for each flow include traffic management, flow control, packet forwarding, access control, and other network management functions. The ability to control network traffic on a per flow basis allows for the efficient handling of a wide range and a large variety of network traffic, as is typical in large-scale computer networks, including video and multimedia traffic. The amount of buffer resources and bandwidth resources assigned to each flow can be individually controlled by network management. In the dynamic operation of the network, these resources can be varied based on actual network traffic loading and congestion encountered.

Abstract: A reduced size field effect transistor is disclosed which has a substrate with a body of semiconductor material having an active region on one surface thereof, and a common conductor located in remote insulated relation to the one surface of the semiconductor body, a pair of source electrodes, a drain electrode and a gate electrode located on the one surface, with the drain electrode having drain fingers located on opposite sides of each of the source electrodes and an air bridge overlying the source electrodes and interconnecting the drain fingers located on opposite sides of each of the source electrodes, the gate electrode having a connection pad at one side thereof and a manifold extending between the source electrodes, and having gate fingers extending between the drain fingers and the source electrodes, and conductive connections between the source electrodes and the common conductor.

Abstract: A universal adapter bracket for installing standard form factor adapter cards such as PCI cards into larger expansion slots of a communications device, such as a router or switch. The adapter bracket has a front face with angled flanges forming an aperture for accepting standard PC brackets, an upper flange with conductive spring clips or foam gasket material, a lower flange for securing a carrier card to the adapter bracket, and fasteners on the front face of the adapter bracket for securing and grounding the adapter bracket to the communications device.

Abstract: A data transfer flow control system for a packet communications system includes a plurality of nodes interconnected by transmission links. The rate at which a sender node transmits information to a destination node in a network is modified in accordance with congestion information returned to the sender node from nodes along the path of the transmission or from the information receiver. The rate change for information being sent from the sender node is modified based upon the amount of elapsed time occurring since the last rate change of the same type. In first and second examples, the rate change is implemented in accordance with exponential and linear relationships, respectively, between the modified flow rate and the elapsed time since the last rate change.

Abstract: In high speed cell switching networks, a Call Admission Control (CAC) procedure is performed on each connection according to a specified Traffic Descriptor. A mandatory parameter of the Traffic Descriptor is the Peak Cell Rate (PCR), associated with a Cell Delay Variation Tolerance (CDVT). Connections which specify a high CDVT value may potentially send into the network bursts of cells at a rate much higher than the declared Peak Cell Rate, which may lead to congestion in cell buffers of intermediate network nodes. Guaranteeing the Quality of Service (QoS) for such connections may require the reservation of a high amount of resources in the network, leading to poor utilization of those resources.