Abstract: The present invention provides the ability to use existing cable TV wires for home networking.

Abstract: An apparatus is disclosed for allocating processing resources, such as instruction execution which can be measured in MIPs or memory capacity, or other resources of a processor itself or resources used in the process of performing operations, such as memory resources, busses, drivers and the like, to functions in a queue waiting to be executed. This apparatus includes a capacity determining device for determining an amount of the processor resource available to be assigned, a load determining device for determining an estimate of an amount of the resource needed for each function waiting in the queue to execute, a prioritization device for prioritizing each of the functions in the queue waiting to be executed, and an allocating device, which receives information from the capacity determining device, the load determining device, and the prioritization device, for allocating the available resource to the functions based on a hierarchical priority scheme.

Abstract: Systems and methods are provided for performing signal processing on communication data utilizing scale reduced Fast Fourier Transform computations. The present invention provides scaling in a Fast Fourier Transform computation at stages where it is determined that bit growth is present and omits scaling at stages where it is determined that bit growth is absent. The determination is based on the characteristics of the input signal. The determination can be made off-line by modeling and/or simulation or in real-time by analyzing the input signal to determine stages at which bit growth is present and/or absent and setting the stage scaling accordingly.

Abstract: A non-robust test pattern, which causes a transition on a path of interest as well as off-paths, may be selected as being suitable for performing delay analysis of the path of interest (e.g., critical path) if the transitions caused on the off-paths would not overlap with the transition caused on the path of interest. In other words, an aspect of the present invention enables at least some non-robust test patterns to be used for performing delay analysis. As non-robust test patterns (as well as robust test patterns) can be used to perform delay analysis, the number of possible test patterns for performing speed analysis can be increased.

Abstract: In frequency channel communications, constraints on transmit power characteristics can be complied with by implementing constellation shaping (15, 71) in the transmitter. In transmitters which use transmit filtering (91) to comply with constraints on transmit power characteristics, the transmitter can also implement, upstream of the transmit filter, precoding (92) designed for a desired cooperation with the transmit filter.

Abstract: A DC—DC CMOS converter including when the supply voltage is low, the current limit is automatically reduced to the maximum possible value that maintains the comparator operative, rather than simply switching off the converter.

Abstract: An ADSL receiver HPF architecture 300 that reduces the number of Op Amps below that required for known ADSL receiver HPFs. The ADSL receiver HPF 300 is implemented as an active RC filter to provide a single fifth-order Elliptic filter instead of the more conventional pair of third-order Elliptic filters. Since the HPF Elliptic filter stage having the lowest Q factor is reduced as the order of an Elliptic filter transfer function is increased, a single fifth-order Elliptic filter suitable for use as an ADSL receiver HPF can be implemented using only one Op Amp in the second 2nd-order HPF stage 308. A notch (imaginary zero) is provided by summing of output signals associated with active RC structure state variables. This structure minimizes the number of capacitors while preserving the capability to provide a high Q factor for the first 2nd-order HPF stage 304.

Abstract: A variety of bi-directional data transmission systems that facilitate communications between a plurality of remote units (15) and a central unit (10) using a frame based discrete multi-carrier transmission scheme are disclosed. In each of the systems, frames transmitted from the plurality of remote units (15) are synchronized at the central unit (10). A variety of novel modem arrangements and methods for coordinating communications between a plurality of remote units (15) and a central unit (10) to facilitate multi-point-to-point transmission are disclosed. The invention has application in a wide variety of data transmission schemes including Asymmetric Digital Subscriber Line systems that include the transmission of signals over twisted pair, fiber and/or hybrid telephone lines, cable systems that includes the transmission of signals over a coaxial cable, and digital cellular television systems that include the transmission of radio signals.

Abstract: A modem (10) for transmitting a discrete multitone modulated (DMT) signal over a communications channel (H) is disclosed. In the encoding of an input bitstream, unloaded subchannels in the DMT spectrum are assigned signal values so that a trailing portion of each block or frame of the resulting datastream are forced to a known value, for example zero. The known-valued trailing portion of each block provides the effect of a cyclic prefix, without necessitating the prepending of an actual cyclic prefix and incurring the corresponding data rate loss; alternatively, the effect of a cyclic prefix can be augmented by the forcing of the trailing portion of the blocks to known values.

Abstract: A method for identification of memory assignment conflicts in the assignment of memory location addresses to a set of buffers. Programs run in embedded processors using buffers in a fixed storage space need to be mapped to addresses which do not overlap or create conflicts. The process of assigning start and end addresses for buffers can be tedious and error prone if performed without automation. The present invention presents a tool that automates the task of mapping the memory buffers and heaps to physical space. The tool utilizes a memory buffer allocation table created by the programer. The table designates the locations, sizes and overlays of all the buffers and heaps. The tool checks the validity of the memory map specified. If it is found to be invalid, the user is notified of the error. Otherwise, a memory table is created which will serve as “hooks” for runtime buffer manipulation.

Abstract: A variety of bi-directional data transmission systems that facilitate communications between a plurality of remote units (15) and a central unit (10) using a frame based discrete multi-carrier transmission scheme are disclosed. In each of the systems, frames transmitted from the plurality of remote units (15) are synchronized at the central unit (10). A variety of novel modem arrangements and methods for coordinating communications between a plurality of remote units (15) and a central unit (10) to facilitate multi-point-to-point transmission are disclosed. The invention has application in a wide variety of data transmission schemes including Asymmetric Digital Subscriber Line systems that includes the transmission of signals over twisted pair, fiber and/or hybrid telephone lines, cable systems that includes the transmission of signals over a coaxial cable, and digital cellular television systems that include the transmission of radio signals.

Abstract: A wireless receiver for receiving an incoming signal having spatial and temporal diversity. The receiver uses noise-based prescaling of multiple receiver chain signals for optimally combining the receiver chain signals in a composite equalized signal and uses noise-based time-varying postscaling the equalized signal. The receiver determines noise-based scale factors by comparing signal symbols to dispersed replica symbols of a training sequence for the incoming signal.

Abstract: A technique that combines a turbo trellis coded modulation (TTCM) coding scheme with constellation shaping and precoding schemes to implement a binary coded communication system and method that can achieve high performance (high coding gains achieved in combination with shaping gain, and when necessary, also with high performance in ISI-channels via preceding).

Abstract: An expert system that provides an analysis of protocol exchanges and protocol relationships across multiple data units, such as packets, of a network and within data units themselves is described. The system collects a number of facts and based on rules governing the data units, new rules and facts are gained from the analysis. The invention is extensible for additional protocols and diagnostics by updating a knowledge database with dynamic rules for any application or protocol desired.

Abstract: A technique for implementing impedance matching circuits 100 that use the transfer functions of each line impedance model. This technique allows implementation of an impedance match for a diverse number of line impedances reusing the same circuit 100 topology, by simply adjusting coefficients to accommodate different line impedances.

Abstract: Contention communications often requires a station to wait an inordinate amount of time before the station is able to transmit its data successfully. In many applications, an extended delay is not acceptable. Contention-free communications in a contention period allows a hybrid coordinator (HC) to schedule contention-free access to a communications medium so that extended delays may be eliminated, and to coordinate contention access to the medium so that better throughput and delay performance is achieved. A method for creating contention-free communications within a contention communications period is presented, along with adaptive algorithms for contention access during the same contention period.

Abstract: A method for detecting a boundary between two sequences in a wireless local area network is presented that permits rapid detection of the boundary. The method includes provisions for proper operation when significant interference and multi-path can degrade the received transmission significantly. Additionally, when a modification is made to the signaling format to signal a special enhanced mode with performance and features above those that are specified in a single technical standard, the method detects the boundary between sequences regardless of whether they have the standard format or the modified format.

Abstract: A state machine for attenuating the transition into and out of NLP state to reduce voice clipping and to reduce echo leak in a voice over packet signal transmission. The state machine interposes two additional transitional states between the NLP active state and the NLP inactive state to eliminate the sharp transition of NLP activity. An NLP entering state is used to gradually reduce the mixing ratio of echo and voice to attenuate the transition from passage of echo in the NLP inactive state to the suppression of echo in the NLP active state. An NLP exiting state is used to gradually increase (ramping the change) the mixing ratio of echo and voice to attenuate the transition from suppression of echo in the NLP active state to passage of echo in the NLP inactive state.

Abstract: A system and method are disclosed to mitigate the interference on DSL due to high frequency components associated with a change in a POTS condition, such as POTS ringing. In response to detecting that a potentially disruptive POTS condition is to about to occur, downstream DSL traffic can be temporarily stopped. The stoppage can include downstream traffic of voice and/or data.

Abstract: For use with a multiple-input, multiple-output (MIMO) transmitter, a signal field controller, a method of controlling signal fields and a MIMO transmitter incorporating the controller or the method. In one embodiment, the controller includes: (1) a primary signal field mode indicator configured to cause a primary signal field to indicate a presence of a supplemental signal field and provide the primary signal field to the MIMO transmitter for transmission thereby and (2) a supplemental signal field generator coupled to the primary signal field mode indicator and configured to provide a supplemental signal field to the MIMO transmitter for further transmission thereby only when the primary signal field indicates the presence.