Abstract: An access device having an input port for connecting to an upstream section of a coaxial distribution cable and an output port for connecting to a downstream section of a coaxial distribution cable, and provides isolation of an RF communication signal from an AC power signal for access by subscriber network service equipment. The access device also includes power conditioning of the AC signal to provide a DC operating voltage over a separate output to operate the respective subscriber network service equipment.

Abstract: Highly accurate, self-calibrating data processors and methods for calibrating the same use internal analog references with negligible time and temperature drifts. A first input reference signal set generated by any accurate, precision analog reference is applied to a data processor. The corresponding output response is compared to the theoretical ideal output response to determine the data processor's initial gain and offset errors. This information can be stored in non-volatile memory, recalled, and used to compensate for the data processor's initial gain and offset errors during actual use of the data processor. Subsequent errors due to time and temperature drifting can be determined by comparing the output responses to a second input reference signal set which is generated by the internal analog reference. The subsequent errors can be combined with the initial errors to compensate for system errors within the data processor.

Abstract: A subscriber network interface for connecting a subscriber premise location to a broadband communication network transporting multiple two-way communication signals, including at least RF analog and RF carrier modulated ATM cells, respectively, includes a coupler for directing incoming communication signals onto, and outgoing signals off of, respectively, at least first and second internal RF communication paths, wherein the first RF communication path includes a bandwidth filter for restricting transmission to, e.g., a CATV broadcast signal, and the second RF communication path is connected to a first modem configured for demodulating and modulating, respectively, the incoming and outgoing ATM cells. A second modem for separately demodulating and modulating, respectively, incoming and outgoing digital baseband signals may also be provided.

Abstract: A dc-coupled receiver for a shared optical system includes an input feedback amplifier circuit which establishes a dc reference baseline voltage level for incoming packets of data. A pair of sample-and-hold circuits are connected in parallel to receive and sample signals from the feedback amplifier circuit when no data is being transmitted and at the initial edge of incoming packets of data. A voltage divider circuit receiving signals from the sample-and-hold circuits establishes a dc slicing level for each incoming packet of data. An output feedback circuit can be added to compensate for offset error without affecting the performance of the sample-and-hold circuitry.

Abstract: A re-enterable environmentally sealed enclosure for housing circuitry and/or cable components of a communication network employs a removable cover attached to an enclosure base by a pivoting cam-tracking system. The tracking configuration positions the cover in a manner that, as it approaches the enclosure base when being closed, a seal located in the cover is evenly compressed along its entire perimeter against a corresponding mating surface on the base, thereby distributing the compressive force equally across the entire seal, with any shear forces substantially eliminated. A single tensioning system is provided adjacent the cam-tracking system, so that the tracking system does not operate as a counter-lever to the tensioning system, and visa versa, thereby improving the distribution of force across the seal.

Abstract: Resonant DC to DC flyback converter topologies having one or more transformers and a primary side resonant subcircuit are optimally controlled by providing independently derived duty cycles for driving the main transformer and resonant semiconductor switches to prevent cross-conduction thereof and minimize reverse recovery losses.

Abstract: An intregal cable retention and sealing apparatus has reusable clamping mechanisms for the entry and exit of a wide variety of cable types and sizes to a sealed enclosure. The device is formed by "mirror-image" body halves having, when assembled, at least one axial passageway formed therethrough to accomodate one or more respective cables. One end of the apparatus includes a chamber for housing a sealing medium, whereas the other end includes a cable retention mechanism.

Abstract: Resonant DC to DC power converter topologies include a PWM-controlled flyback converter having a single transformer and a primary side resonant subcircuit that is optimally controlled to minimize reverse recovery losses. A second transformer may be added wherein the primary windings are connected in series, the first transformer having substantially greater inductance than the second transformer to more efficiently transfer energy over a wide range of output load conditions. A combined forward-flyback resonant converter utilizing a load-side buck loop for increased power delivery performance and start-up circuitry for initial power connection of the converter to a voltage source utilizing a hysteresis protection circuit are also disclosed.

Abstract: An optical modem link for full duplex transmission of multiple, independent RF carrier signals between network elements of a Broadband Access Network, includes a first optical modem, e.g., at a CATV headend broadcast facility, linked by a single optical fiber with a second optical modem, e.g., at a distributed hub location, to form an optical modem link. Each optical modem end of a respective link is equipped with an optical transmitter, which transmits light signal having a first wavelength, a receiver which receives a light signal having a second wavelength, and a wavelength division multiplexer which directs the outgoing light signal onto, and the incoming light signal off of, respectively, the fiber link.

Abstract: A circuit for controlling an extinction ratio of a laser whose temperature can change over time includes first and second feedback loops which monitor a LOW output power of the laser during a first frame training pulse and a HIGH laser output power during a second frame training pulse. The LOW power output is compared to a preset dynamic LOW power reference, and a LOW bias current applied to the laser is incrementally increased or decreased so as to keep this LOW power output toggling about this LOW reference. Similarly, the HIGH power output is compared to a HIGH power reference, and a modulation current for the laser is incrementally increased or decreased to keep the HIGH laser output power toggling about this HIGH reference. Preferably, the training pulse is sent once per frame thus enabling both the LOW and HIGH laser output powers to be kept constant regardless of whatever dynamic variables may change over time thus keeping the laser extinction ratio constant.

Abstract: Alternative methods and apparatus for introducing narrowcast transmission signals into a fiber optic broadcast network utilizing rare-earth-doped fiber amplifier technology are disclosed. The methods and apparatus include utilizing an existing 1480 nm pumping laser in an erbium-doped fiber amplifier to transmit a narrowcast signal into a 1550 nm broadcast transport fiber. The 1480 nm narrowcast signal is split off from the amplified 1550 nm broadcast signal(s) in order to bypass a 1550 nm optical isolator located at the output of the amplifier and then recombined with the broadcast signal(s) after the isolator.