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 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.

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: In a SONET-access product, channel-associated signaling is rearranged into SONET-formatted signaling, with the signaling for added channels being multiplexed with the signaling for through channels, in accordance with a control signal received from a channel map RAM, which stores one bit of data for each channel to indicated whether it is a through channel or an add channel. The RAM is provisioned by a network control processor.

Abstract: A SONET pointer interpretation in system which an Alarm Indication Signal (AIS) of a first type is interpreted as a subset of Loss of Pointer (LOP) of a first type. Specific events are defined for entering an AIS type 1 state and for exiting this state. Specific events are also defined for entering an LOP type 1 state and for exiting this state. Finally, a truth table is defined for mapping these states into a valid pointer (NORM) state, an AIS of a second type state and an LOP of a second type state.

Abstract: An in-line piece-wise linear desynchronizer eliminates the need for very low bandwidth analog, phase lock loops to smooth phase jumps caused by pointer changes such as those associated with a DS-1 signal mapped into a SONET VT 1.5 payload. The desynchronizer comprises a digital elastic store position detection circuit, a digital frame induced jitter filter, a digital leak rate filter, and a digital frequency synthesizer (VCO). The magnitude of the jitter can be reduced to any level by adjusting the digital VCO resolution and digital leak rate filter time constant. The desynchronizer produces a digitally synthesized output clock which can then be coupled to an analog/digital phase lock loop for smoothing high frequency jitter in the synthesized output clock, thereby providing an in-line interface function.

Abstract: A heat generating means, such a resistive element, is serially connected in a current-carrying conductive line, and a fusible link carrying current from said line is serially mounted between the line and said resistive element and is positioned in proximity to the heat generating means, to be heated by the heat from the generating means and to melt in response thereto, thereby breaking the serial connection in the current-carrying line. A spring means may be provided to urge disconnection of the serial circuit when the fusible link melts.

Abstract: A partial word to full word parallel data shifter comprises 2N-1 multiplexer for selectively receiving data from the incoming current data word of width up to N, or from remainder bits of previously received data. The multiplexers output their data to 2N-1 latches, N of which output a full parallel data word and N-1 of which can recirculate up to N-1 remainder bits back to the multiplexers. If the number of remainder bits plus the number of data bits for the currently received word is less than N, the bits in the first N latches are not output but rather recirculate to the multiplexers where they are aligned for generating a full N bit output word with the most significant bit(s) of the next incoming parallel data.

Abstract: In an optical fiber telecommunication transmission system, a remote terminal interfaces a high-rate optical fiber feeder line and a plurality of lower rate optical fiber distribution lines. The remote terminal includes a plurality of interfacing and signal cross-connecting devices which interface and cross-connect lower rate telephony signals with higher rate telephony signals. The plurality of interfacing and cross-connecting devices are interconnected with high-rate transmission lines so that telephony signals from under-utilized optical fiber distribution lines may be concentrated onto the high-rate optical fiber feeder line for efficient use of the feeder line.

Abstract: A snap fit cable retainer is illustrated for accommodating multiple diameter cables in a snug fit configuration by having the bit portion between adjacent side legs being closer to the extremities of the legs than is the main bit portion of the overall connector. In this way, large diameter cables can be run lengthwise through the retainer and smaller diameter cables can be run crosswise through the retainer. The retainer can also accommodate a layer of cables in each direction simultaneously by placing the lower level in the crosswise direction through the retainer and the second layer on top in the lengthwise direction.

Abstract: In an integrated telecommunications network adapted to provide narrowband telephony signals and broadband switched video signals, control signals for the broadband video signals are transmitted in the narrowband as baseband signals, which are frequency division multiplexed with the broadband switched video signals. The video control signals are transmitted over the same transmission lines as the broadband video signals and do not require the installation of additional transmission lines. Control signals from a plurality of subscribers are multiplexed together at a network unit and are transmitted as a channel on an optical fiber, after which the channels from a plurality of network units are further multiplexed together to form a frame of control channels which are transmitted to a video controller unit.

Abstract: A video line shelf arrangement allows for incremental growth in video channels provided to optical network units. The arrangement includes a number of video line shelves disposed vertically in a column. Each video line shelf includes a number of slots, with the slots of adjacent shelves being aligned vertically. Video line cards each providing six video channels are inserted into selected slots of the video line shelf, as are necessary to provide the required number of channels. A vertical column of video line cards is arranged to service a single optical network unit. Thus, only the necessary number of video line cards are inserted into the slots aligned in a column serving a single optical network unit.

Abstract: A terminal for a telecommunications system provides access to one or two high-speed synchronous transmission lines by both low-speed transmission lines and subscriber lines. A core module includes interfaces to the high-speed lines, a time slot interchanger, an interface to the low-speed transmission lines, processors and overhead circuitry for supporting the terminal. An access module includes a plurality of line shelves connected to subscriber lines, each line shelf includes a pair of processors and for time slot assignors. A multi-link serial bus connects the time slot interchanger to the access module and to the low-speed interface and provides close coupling between the processors in the core module and the line shelves. The processors cooperate to groom subscriber information from said subscriber lines to and from time slots in said high-speed feeder line and said low-speed transmission line.

Abstract: A connector retainer is illustrated for use with at least two inline sets of right angle electrical connector pins whereby the connector retainer flexibly partially encloses and interlocks with the connector and has an extension thereof inserted in the right angle portion of the electrical pins wherein the inserted portion is of a larger diameter than the distance between the inline sets of pins. Such a portion can fit in the right angle portion between the sets of the pins and provide a hinge-type function without being able to move either horizontally or vertically thereby retaining the connector in contact with the electrical pins.

Abstract: A snap fit cable holder in a U-shape with two legs is shown with snap fit projections on both the inside and outside of the legs of the holder and at different relative heights with respect to the bit portion of the device. In this manner, the legs can be inserted through first and second openings to be held by their inside edges of the openings or can be inserted in first and third openings to be held by the outermost edges of the first and third openings. This allows a single cable connector to be used with at least two different size cables. Further variations may be obtained by adjusting the thickness of the support base containing the openings.

Abstract: A bandpass filter is used, which closely matches the characteristics of a closed phase lock loop (PLL) so as to provide an acquisition detector output in a PLL being swept. This detector is not activated by noise generated in the loop due to data or other perturbations. This filter includes a differentiator to exacerbate the filtered output and thus, more clearly define the condition being detected. The phase lock acquisition sweep is disabled when the detector output exceeds a predetermined absolute value. The detection scheme works equally well in approaching the lock frequency from above or below actual lock and a latch circuit ensures that the sweep approach always alternates to compensate for an erratic phase detector in the PLL.

Abstract: The present invention provides an approach to reconnect a communications network such as a DS3 telephone-type network when a span of DS3 channels is rendered inoperative, such as by cutting, within the 1.5 second time frame necessary to prevent disablement of local offices. This is accomplished by preplanning a restoration connection for each possible operating link failure in each span using spare capacity. A dedicated (DS3) communication loop is used to inform all nodes in the network substantially simultaneously to implement their portion of a plan associated with the failed span. After the restoration occurs for a given failed span, the concept can be extended to start planning for further failures or can be designed to restore further failures on a real time basis.

Abstract: The four signaling bits contained in the eight-bit SONET signaling bytes are read from the SONET signaling row and are converted to four parallel signaling bits for storage in a RAM in quasi-SONET format, with sets of four A, four B, four C and four D bits for four consecutive channels being stored for an even and an odd tributary in one RAM memory row. Storing sets of four of the same bit for four consecutive channels simplifies the RAM write operation. A read-modify-write system is used for updating the RAM storage, wherein a row of RAM is read, modified by eight new signaling bits from two consecutive SONET signaling bytes, and is rewritten into the RAM. New signaling bits are stored to accumulate eight new signaling bits for two tributaries prior to updating the RAM with the new bits for both tributaries. The 32 signaling bits output during a RAM read operation are selectively multiplexed to output only four bits associated with a particular channel.

Abstract: A method is shown, along with apparatus for accomplishing same, for minimizing power required to keep an enclosed electronic module from overheating in a high temperature environment, while still operating to maintain the module at greater than a given minimum temperature when the environmental temperatures are far below the sensed minimum temperature for the module. This is accomplished by placing a thin sheet of heating material between the module to be temperature maintained and a heat sink which is exposed to the environment exterior the enclosure. Energy applied to the sandwiched heater prevents transfer of heat from the electronic module to the environment in such a way as to drastically reduce the heat (power consuming) requirements as compared to prior art heater approaches.

Abstract: Two pulse-width modulated power supplies are synchronized to operate at 180.degree. of phase shift to reduce the peak amplitude of the instantaneous current drawn from the DC input bus. The circuit includes means for disabling the synchronization upon detection of an undervoltage fault condition on the output of either supply. This feature allows frequency programming techniques to be used to provide foldback current limiting for either supply without affecting the operation of the other supply.