Abstract: All available timeslots for interconnecting a circuit between two endpoints in a telecommunications network are considered for selecting and establishing the path wherein the selecting step may be carried out according to the rule of first feasible timeslot and wherein bandwidth may be determined as being equal to the lowest count among the timeslots determined to be feasible in each network element in a given path and wherein the total bandwidth in the network between two endpoints is determined by adding the bandwidths determined for each possible path.

Abstract: A message priority scheme for use in local areas networks (LANS) operating in accordance with carrier sense, multiple access/collision detect (CSMA/CD) bus access protocol. A LAN station having a high priority message to send ignores the carrier sense signal, and thereby obtains immediate bus access. If the high priority message collides with another message already on the bus, both messages are subject to a backoff period. However, the backoff period for a high priority message is guaranteed to be less than that of a low priority message for a certain number of re-transmission attempts. An intermediate priority status is assigned to a message that previously had a high priority status, after a certain number of transmission attempts. The intermediate priority message is deprived of its ability to transmit while ignoring the carrier sense signal, but retains its shorter backoff period.

Abstract: A local area network interface for a network element having redundant processors is made by using a pair of connectors for each processor. A delay line is used between pairs of connectors for non-redundant LAN configurations. For redundant LANs, the delay line is not used.

Abstract: An EMI/RFI gasket provides a barrier to EMI and RFI radiation transmission to and from electronic circuits within an electronic system chassis having receptacles that receive electrical connectors and an electrically grounded cover plate that connects the chassis to an electrical ground. The EMI/RFI gasket helps to provide a 360.degree. EMI/RFI barrier for the electronic system chassis. The EMI/RFI gasket is a flexible, electrically-conductive material with sufficient surface area to adhere and electrically connect to the cover plate. The EMI/RFI gasket has a receiving slot that is symmetrical about a longitudinal axis and a latitudinal axis of the gasket plate. A plurality of deflected teeth formed from the gasket plate are positioned around the receiving slot and deflected from the gasket plate to contact the connector at points separated by not greater than a predetermined distance. The predetermined distance is at least in part a function of the expected EMI and RFI radiation wavelengths.

Abstract: The invention disclosed includes both a method and apparatus for affixing an optic fiber tip in position with respect to a fiber communications circuit. In one embodiment of the method, a glass positioning member is located proximate the tip of the optic fiber. In another step, the glass positioning member is affixed to the fiber at a first position with respect to the fiber tip. The glass positioning member is also affixed in a second position with respect to the carrier. In a more detailed embodiment, the method of the present invention includes positioning the optic fiber through a channel of the glass positioning member. Heat is applied to the glass positioning member causing it to soften such that its channel collapses around and fuses to the fiber. In still further detail, the fused positioning member/fiber are affixed to a block, and the block is fused to a carrier.

Abstract: A circuit for maintaining a constant voltage across and constant current through an RF cavity includes a RF cavity comprising a common-gate or common-base transistor associated with a current control circuit maintains a constant current flowing through the RF cavity. The current control circuit has a current control BJT associated with the RF cavity and a resistor between the emitter of the current control BJT and the negative source voltage of the RF cavity. The current control BJT and resistor operate as a current source or sink as necessary to maintain a constant current flow through said RF cavity. A constant voltage regulation portion of the circuit maintains a constant voltage across the RF cavity and includes a zener reference diode and a voltage regulation BJT.

Abstract: A bit resolution phase detector can be realized for a parallel elastic store by comparing a write bit clock and a read bit clock to determine when stuff bits are required; upon detection of phase alignment between the write and read clocks, the phase detector will output a signal which will enable the insertion of a data bit into the stuff opportunity bit and cause the write clock to lag the read clock by one bit period.

Abstract: A method and system for handling transport overhead on a ring network. The system includes a ring network having a plurality of network elements communicating a signal along the network. In one embodiment, a method is provided for restoring transport overhead along the ring network. This method includes designating a first of the plurality of network elements as a master network element and inserting a first transport overhead break on the ring network by the master network element. The method further includes detecting a failure of the signal by a second network element and inserting a second transport overhead break on the ring network by the second network element in response to the detection of a failure. Finally, the method includes removing the second transport overhead break under the direction of said master network element.

Abstract: A system of managing memory used by communications tasks of a communications network operating with a multilayered communications protocol. Specially formatted buffers are used to contain data to be passed down the protocol stack of a source node, across a communications link, and up the protocol stack of a destination node. Before entering the source stack, message data is presegmented so that each buffer contains only so much message data as may be transmitted as a single data unit from source to destination, even after all layers of the source stack have added layer headers to that portion. Then, when the buffers are being passed within the source stack, any layer may segment the message data by simply unlinking buffers and adding its layer header to each segment. Inter-layer data passing is by means of exclusive access to buffers by one layer at a time. At the source stack, any layer that must send multiple copies of the message data may checkpoint the buffers and thereby regain the same buffers.

Abstract: A springy, low dielectric retainer device in the form of a rod, a triangle, an ellipse or whatever, is used in a compressed condition to hold RF energy absorber blocks in position juxtaposed "energy leaky" RF circuitry. The absorber blocks are held in position due to frictional forces provided by the compressed retainer. In this manner, the absorber blocks can be re-positioned to obtain optimum amplitude/frequency response characteristics from the affected RF circuit.

Abstract: A circuit is shown for arbitrating between inputs to provide all request inputs with the opportunity to be polled in substantially less time than is the case with known prior art round robin arbiters. This is accomplished by phase delaying the input clock to produce a plurality of different phase clock signals such that multiple arbiter circuits can be polled within a single clock cycle if the first few arbiter circuits do not have a request waiting. With proper speed of operation of arbiter circuits, the phase delay can be of a short enough duration that all of the arbiter circuits can be polled in a single clock cycle. With slower speed arbiter circuits, the total polling time can exceed one clock cycle but still be less than the number of clock cycles of prior art round robin circuits which typically was the number of arbiter circuits times a single clock cycle time duration.

Abstract: A routing method, performed by intelligent network elements of a data communications network having SONET applications, for selecting a path from a source network element to a next network element. Each network element has access to a database containing the addresses of its neighboring network elements and their types. To select a next network element, a routing network element first attempts to find a neighboring network element that is the same as the destination network element. If it has no such neighbor, the routing network element then attempts to find a neighbor that is in the same area as the destination, or failing such a neighbor, in the same routing domain. Optionally, the routing network element looks for a neighbor that has been selectively provisioned as a next network element. At each step, candidate network elements are eliminated by using data about their type and application to determine if they call for duplicate paths.

Abstract: A power coupler that is held in place at two different points along its length to substantially eliminate any movement thereof due to vibration of the environment. One of these holding means comprises a piece of dielectric which snugly encloses the coupler to prevent side-to-side movement while still allowing a vertical adjustment of the coupler element through the holding means. A constant impedance equal to that of an electrically connected circuit is maintained along a portion of the coupler by varying passageway opening sizes. The electrical connection to the circuit, which has a threaded terminal comprising a part of the adjustment means and the other holding means eliminates connector insertion loss and signal reflections inherent in prior art signal interfaces between the coupler and an electrical signal receiving circuit.

Abstract: An optical splice shelf (10) has optical splice trays (24, 26, 28, 30) stacked inside a frame assembly (14) slidingly withdrawable from a rear panel (12) and attached thereto with cable tray hinge (80) for maintaining no less than a minimum bend radius of optical fibers routed between the rear of the frame assembly and the rear panel; upon withdrawal, the frame assembly can be pivoted downward to expose the rear panel and the back of the frame assembly.

Abstract: A concept previously used for providing anti-rotational locking of complementary threaded devices is utilized in a RF tuning cavity to minimize anti-microphonic disturbances of the prior art caused by inconsistent ohmic contact between the prior art adjustable length threaded portions. The use of a resilient locking strip embedded longitudinally into the threads of an adjustable resonator provides substantially constant electrical or ohmic contact between the two threaded portions so as to maintain a standing wave in the tuning element. The longitudinal design of the locking strip is such as to prevent or minimize movement of the extremity of the threaded resonator which movement can also effect the resonant frequency.

Abstract: A method is illustrated for identifying which one of a plurality of signal transmitting spans in a communication network of signal spans, such as bundles or sets of DS3 signals, has been interrupted by some type of failure. This identification is based on a local level knowledge, as opposed to prior art network level knowledge, by monitoring each circuit in a given span for either a directly observable signal impairment, or an alarm indication signal (AIS) and sending an IDLE whenever a directly observable signal impairment or an alarm indication signal is detected and declaring that the channel immediately upstream from that node has failed when either the directly observable signal impairment or the alarm indication signal is received for longer than a predetermined period of time. Such a determination as to the whereabouts of a failed span can then be used for other processes such as implementation of a network restoration scheme.

Abstract: A method and system for multiple WDM signal compensation compensates optical chromatic dispersion for a plurality of optical signals having predetermined frequencies and each traveling in an optical path associated with the wavelength division multiplexer that forms a multiplex optical signal from the plurality of optical signals. The invention first undercompensates the multiplex optical signal by a predetermined amount so that each of the optical signals has an associated residual optical chromatic dispersion. Then, either before or after undercompensating of the multiplexed optical signal each of the optical signals is individually compensated to remove therefrom the residual chromatic dispersion. The system and method permit simultaneous and independent control of optical dispersion at any desired wavelength, as well as selection of matching compensation for optical transmitters prior to installation. The result is an increase in the usable wavelength range of optical signals for WDM networks.

Abstract: The present invention provides a method and system that compensate end-to-end optical dispersion for a fiber-optic cable having a plurality of predetermined compensations sites to within a predetermined dispersion limit using a predetermined dispersion compensation increment. With the method and system, the predetermined dispersion compensation increment may exceed both the predetermined compensation limit as well as the compensation limit divided by the number of sites. The method includes the steps of compensating optical dispersion using the compensation increment for each of the plurality of predetermined compensation sites to yield an end-to-end optical dispersion compensation within the predetermined optical dispersion limit. This may include optical dispersion over-compensation at some sites and optical dispersion under-compensation at other sites.

Abstract: A connector for connecting coaxial cable to a microstrip transmission line on a substrate is disclosed. The connector includes tapped threaded holes in a mounting plate, and an extended throat between the mounting plate and the threaded coaxial coupler. The threaded holes and extended throat allow for the mounting of the connector on the inner surface of the chassis wall, for example within a machined cavity or within a stamped dimple. The chassis bolt holes are oversized, to allow for fine adjustment of the vertical and lateral position of the connector on the chassis wall relative to the transmission line trace. The resulting connection has reduced UHF signal attenuation, and also a higher reliability connection to the transmission line.

Abstract: A system is illustrated that uses a spare or auxiliary add-drop muldem located at each end of N high capacity transport circuits to form a ring-type protection circuit using one additional high capacity transport. This is accomplished by using error detection circuitry to switch all of the auxiliary muldems to be normally in a high speed input/output circuit LOOPed condition but switching the auxiliary muldems on either end of a "bad" circuit to a THRU or open condition upon detection of a problem and allowing signals to be routed through the protection transport mechanism rather than the normal transport mechanism.