Abstract: The present invention enables multi-windowing agent computer terminals, that answer a variety of, e.g., telemarketing calls, to (i) receive call-related information from a communication system at an agent terminal for automatic display in a "telephony" window, and (ii) automatically send such information to a host computer system application software and retrieve caller desired information based on the calling or called number for display in a "host application" window without requiring a caller to provide verbal information. The present invention also enables an agent terminal to automatically transfer caller-related information from one window to another window via programmable function key commands which can be programmed by a user/system administrator regarding what information is to be copied and where and when to copy it.

Abstract: The present invention relates to a computer-implemented technique for drawing directed graphs providing reduced crossings and improved picture quality. An edge list description provided by a user is processed to produce a ranking of all nodes that minimizes the weighted sum of all edges, an edge cost being the product of its weight and length. Nodes within a ranking are then positioned to reduce edge crossings using a heuristic based on node positions in adjacent ranks. Such heuristic uses a generalized median as a weighting function plus node transposition to avoid senseless edge crossings before proceeding to a next rank. Nodes are then positioned to minimize the weighted sum of horizontal distances among connected nodes. Spline control points are then computed for interconnected nodes, and a code sequence for a drawing is generated.

Abstract: The present invention relates techniques for bidirectionally converting between a first format comprising N concurrent serial bit streams and a second format comprising a parallel TDM bit stream of N words using an array of storage elements, each bit stream comprising M-bits per word. In operation, the N words of the input bit stream(s) are sequentially shifted in a predetermined direction into the array of storage elements so that the N words lie parallel to each other along a first axis of the array. During the last clock period of the N words, the data associated with the storage elements not lying on a predetermined diagonal of the array are transposed across the predteremined diagonal so that the N words lie parallel to each other along a second orthogonal axis of the array. The transposed words are then shifted out of the array in the predetermined direction to provide an output for the converted output.

Abstract: The present invention relates to a multichannel multihop lightwave communication network which allows packet concurrency in the network while avoiding the need for agile optical devices. The network comprises a lightwave communication medium (10) for supporting a plurality of independent user nodes; and a plurality of N network interface units (NIUs) (11). Each NIU is connected to the lightwave medium and one or more separate user nodes and comprises a trnasmitter section (28-35) and a receiver section (20-27) which are each fixedly assigned to transmit and receive, respectively, over a single channel or a plurality of separate channels to or from other NIUs of the network. In a connectivity pattern for one embodiment of the network, the NIUs are divided into k groups of p.sup.k NIUs such that each NIU of a first group of p.sup.

Abstract: The present invention relates to a self-synchronous spread spectrum transmitter and an associated remote spread spectrum receiver which communicate with each other by the transmission of both (1) a spread spectrum Pseudo Noise Code (PNC) sequence signal, and (2) a combined PNC sequence plus the data information (PNC+data) signal. The two signals can be transmitted concurrently using either different frequency bands or on a quadrature carrier; or the two signals can be transmitted with a time offset between signals. At the receiver the PNC and the PN+data signals are separately recovered for the case of the concurrent transmission techniques, and directly mixed to despread the received signal and recover the data signal at baseband.

Abstract: The present invention relates to a transition wherein a microstrip line, formed on one major surface of a substrate, is capacitively coupled to a reduced-height waveguide, comprising a predetermined width-to-height ratio, by means of a T-bar conductive pattern formed on a substrate at the end of the microstrip line. Such T-bar transitions can also be connected on opposite end of the microstrip line to provide connections between two waveguide sections.

Abstract: In a time division multiple access satellite communications system having a master station and one or more remote stations, frequency offset through the translation oscillator in the satellite is corrected by transmitting a pilot frequency signal, reference to a high precision oscillator, through the satellite, so as to subject the pilot frequency signal to a frequency translation and monitoring the frequency translation of the pilot frequency signal as received at the master station subsequent to its transmission through the satellite. Signals to be transmitted over the satellite communications link from the master station to remote stations are subjected to a frequency translation that is effectively complementary to the monitored frequency translation.

Abstract: The present invention relates to a technique for suppressing intermodulation products introduced by nonlinearities of a laser in a multicarrier Freqeuncy Division Multiplexed (FDM) fiberoptic link. More particularly, for two or more closely spaced FDM channel information signals within a predetermined band of frequencies in an FDM optical transmission system, third-order intermodulation products, which are produced by nonlinearities of a transmitting laser, also fall in-band and provide interference in the channel information signals.

Abstract: A contention mechanism is disclosed for a communication network that provides perfect scheduling to avoid collisions between packets from a cluster of M circuit boards connected to a communications bus. The contention mechanism includes a 2-phase contention procedure comprising a first phase priority contention phase, where boards with a highest priority and a real data packet to transmit proceed into a second contention phase, where a pointer is used to declare one of the remaining priority phase circuit boards as the overall winner to transmit its packet during a subsequent packet period. When no circuit board has a packet to transmit, all M circuit boards are declared as winners of the first priority phase, and a board is declared the winner on a distributed basis to transmit a "dead-space" packet over the bus.

Abstract: The present invention relates to an optical backplane for use in a switching system or computer for interconnecting a plurality of associated circuit modules. The backplane comprises a switch which is interconnected to each of the associated circuit modules by a separate multifiber ribbon, each ribbon including (1) a plurality of transmit and receive optical fibers, and (2) an optical fiber for providing concurrent synchronization signals to each of the associated circuit modules. The switch includes a switching block for coupling parallel optical signals received from the plurality of receive optical fibers in any multifiber ribbon, transmitted by a sending module, to the transmit fibers of each of the multifiber ribbons for transmission to all of the modules associated with the optical backplane.

Abstract: The nonlinearity of the frequency response of a solid state power amplifier (SSPA) is obviated by effectively operating the SSPA at the 1 dB compression point, where the nonlinearity does not exist, and controllably reducing, downstream of the SSPA, the power output produced by the SSPA to the level required by the link. In particular, the output is reduced by controllably inserting a relatively thin tapered blade of ferrite material into a waveguide coupling section downstream of the SSPA. Preferably the ferrite material is comprised of a robust carbonyl steel of sufficient thickness to withstand the heat induced in the course of its absorbing microwave energy at the SSPA output, while being of a narrow or thin configuration and oriented for insertion into the absorbing section of waveguide so as to not effectively alter the characteristics of the signal profile of the electromagnetic wave.

Abstract: The present invention relates to a technique for providing phone management (PM) services to personal computers (PCs) which are end users of a PC-only Local Area Network (LAN) by logically associating voice terminals of a separate voice and data Network, e.g., a Private Branch Exchange (PBX), with the PCs. To provide the PM services, a PM server device is provided as an interface between the PC and PBX Networks onto which are bridged appearances of the logically associated voice terminals. The PM server device includes hardware and PM server application software that perform routing and translations between (1) PM messages of the PC-LAN which use a first PM signaling protocol, and (2) PM messages of the PBX which use a second signaling protocol. Each end user PC of the PC-LAN that is logically associated with a voice terminal on a PBX network includes PM user application software that provides a PM user interface and terminates the first PM signaling protocol.

Abstract: The present invention relates to a method for providing noise fill in a communication system. The method comprises the detecting (16) of active and inactive information signal transmission periods to a destined end user, and the measuring (17) of background noise normally found in the transmission of the information signals to the destined end user. A noise fill signal is generated (21,22) and transmitted to the destined end user during information signal transmission gaps to that end user, which noise fill signal is at level below that of the measured background noise. Such attenuated noise fill level was found to provide improved subjective performance in, for example, speech transmissions when the noise fill is between -dB and -6 dB of the measured background noise level, with best subjective performance noted between the -3 and -6dB noise match levels.

Abstract: The present invention relates to a N.times.N single-mode optical coupler employing evanescent wave coupling between mutually adjacent optical waveguides sufficiently close to one another to facilitate coupling among all the waveguides. An optical signal of a narrow frequency band, e.g. appreciably less than 100 gigahertz, introduced to an input port of one of the waveguides is found to be nonuniformly distributed among the output ports of the coupler. A first embodiment uses the nonuniform distributions of narrowband optical signals to the output ports of the coupler to enable the present invention to be used as essentially a selective switching device. A second embodiment introduces one or more predetermined broadband optical signals to one or more input ports of the coupler to produce an appreciably uniform power distribution among the output ports of the coupler.

Abstract: An apparatus and method are disclosed for fabricating an expanded beam cylindrical terminated optical fiber taper from a reduced diameter preform rod. The present invention comprises uniformly heating the circumference of a predetermined portion at an intermediate point of the preform rod to a predetermined temperature and then uniformly pulling the preform rod while continuing to heat additional material of the preform rod to produce a pair of expanded beam cylindrically terminated optical fiber tapers connected by a predetermined length cylindrical central section of standard optical fiber having a uniform diameter less than that of the original preform rod.

Abstract: The present invention relates to a high-speed high-capacity Local Area Network (LAN) wherein each user, of a separate group of one or more of the network users, communicates cordlessly, using radio frequencies or infrared, with an assigned Regional Bus Interface Unit (RBIU) located in the proximity of the group. Each RBIU of the network interfaces with a high-speed serial or lower speed parallel bus of an open-ring network for purposes of transmitting information signals while receiving information signals via the high-speed serial network bus (es), Various communications protocols such as, for example, CSMA/CD, slotted ALOHA, etc. can be employed by the users in communicating with the associated RBIUs with high efficiency due to the short paths involved relative to the transmission frame durations used on the bus.

Abstract: The present invention relates to a technique for repelling carriers in a Frequency Division Multiplexed (FDM) lightwave communication system to minimize mutual interference between signals. The system comprises a plurality of transceivers (20), each comprising a transmitter section (30) and a receiver section (40) which is coupled to a separate user of the system on one side, and on the other side to a lightwave communication arrangement (21-23) that interconnects the plurality of transceivers. Each of the transmitter sections of the system uses a separate carrier (10-14) for transmitting an associated users' information signal, and, during each sequential test cycle period, slowly dithers this carrier in random order to a first nearby frequency (50), on one side of the nominal carrier frequency, and then to a second nearby frequency (51) on the other side of the nominal carrier frequency.

Abstract: The present invention relates to packet switched interconnection protocols for use in high-speed optical Star-configured Local Area Networks (LANs). In the present Star LAN, a plurality of N+1 wavelength division multiplexed (WDM) channels are provided for use by M transceivers connected to the Star coupler, where preferably M>N. N of the N+1 WDM channels are used for transmission of data packets, and the remaining WDM channel is used by all transceivers for transmitting control packets only. In the present protocols, a transmitter in an active transceiver first send a control packet over the control channel using a first protocol such as, for example, ALOHA or CSMA. The control packet includes (1) the transmitter's unique address, (2) the destined receiver's address, and (3) the address of the data channel to be used in transmitting the associated data packet.

Abstract: The present invention relates to an optical upconverting or downconverting gain or loss modulating mixer and a receiver for subcarrier optical communication systems using this mixer. The optical mixer can be formed, for example, from an optical amplifier including a semiconductor laser chip comprising a p-n junction with an active region channel formed along the junction. An optical signal received from the communication system is directed into one end of the channel, and a combination of a D-C bias signal and a local oscillator signal is concurrently impressed on the chip to gain-modulate the received optical signal and produce an upconverted or downconverted output signal. In the receiver, the upconverted or downconverted output signal from the gain-modulated optical amplifier is detected by a photodetector, amplified if necessary, filtered and then demodulated before transmission to the output utilization device.

Abstract: The present invention relates to a wideband communication network using wireless radio transmissions either on a stand-alone basis or to supplement a hard-wired network. The exemplary network comprises (a) a plurality of transceivers associated with separate users of the network; (b) optionally at least one concentrator associated with certain separate subgroups of wireless and possibly hard-wired transceivers for providing duplex operation; and (c) a central node (i) capable of providing both duplex communications directly via a radio channel using radio links with certain subgroups of the transceivers and via a hard-wired connection with each optional concentrator, and (ii) for polling the needs of all transceivers and directing all packets of information from active transceivers through the central node and to the destined transceivers during each frame period.