Abstract:
The call data and hardware cache for a dial-up access concentrators caches the hardware device setup and the communication connection data created for a call connection for use in the next successively received incoming call. The call data and hardware cache for dial-up access concentrators enables the existing physical hardware connection that comprises the call connection in the dial-up access concentrator, the call processing and call connection resources to remain available for use in the next successively received incoming call. This step also retains the communication connection data comprising the call setup and call management data in the shelf controller and the call processing data in the call signal processor card for possible reuse. If the next received incoming call is substantially similar in characteristics to the last terminated call, then the existing nullon-holdnull signal processing card and shelf controller data as well as the TDM connections therebetween can be reused with minor modifications to serve the incoming call. This reduces the time required to setup a communication connection for the received call and reduces the need for CPU resources.
Abstract:
A method and apparatus for carrierless amplitude and phase CAP encoding of data in a manner avoiding the use of pulse shaping filters for in-phase and quadrature impulse signals. Specifically, in-phase and quadrature vector arithmetic structures (VAS) to adapt respective in-phase and quadrature impulse components to produce appropriate shaped in-phase and quadrature components.
Abstract:
A logic circuit with improved performance when operating at the limits of the transistor's bandwidth. In particular, a latch includes a clocked trans-admittance stage circuit for receiving a voltage and producing a current output, and an active load, such as a trans-impedance stage circuit, connected to receive as input the current output of the trans-admittance stage circuit and produce a voltage output. Two independent trans-admittance and trans-impedance stages may be combined as a single latch pair. One or more latch pairs may be arranged in series as a cascaded chain and connected to the output current of a clocked trans-admittance stage latch.
Abstract:
A method for use in a cellular communication system is disclosed which dynamically assigns a communication device to a cell site and which dynamically assigns transmit power levels to the communication device. The method is based on measurements of interference levels at cell sites and on the path gain between the communication device and the cell site.
Abstract:
A method and apparatus are disclosed for measuring the usage of a communications network, based on a two level sampling and measuring technique. A sampling interval, T, represents the intervals at which the network resource is observed. In addition, during each sampling interval, a measurement window of length, null, is utilized. Generally, while the values for the sampling interval, T, and the measurement window, null, are calibrated, actual measurements are only taken for the smaller measurement window, null, and the actual measurements are extrapolated to estimate the usage over the larger sampling interval, T. The sampling interval, T, and measurement window, null, values may be periodically recalibrated. An extrapolation process consists of two phases: (i) a nulllearning periodnull (LP) during which both exact and extrapolated measurements are performed, the error is determined, and, if necessary, adjustments are made to the values of the sampling interval, T, and the measurement window, null; and (ii) a nullmeasurement and extrapolation periodnull (MEP) during which only measurements during the sampling interval, T, continue and the sampled measurements are extrapolated without performing the exact measurements. Several learning periods, LPs, may be interleaved during a communication session with larger measurement and extrapolation period, MEP, intervals.
Abstract:
In accordance with the invention, a modulated RZ pulse source comprises a modulated light source optically coupled to a stabilized Bragg grating filter and one or more optical taps. The light source is preferably modulated in power and frequency and has an adjustable channel wavelength null. The Bragg grating filter has a reflectivity bandwidth having a high slope reflectivity cutoff and is preferably tunable. A feedback arrangement responsive to the taps keeps the source channel wavelength null on the edge of the reflectivity bandwidth for shaping RZ pulses. When the Bragg grating is stabilized, the feedback system maintains null at a value linked to the grating reflectivity edge and, by overlapping at least part of the optical spectrum of the source, converts the modulated source light into RZ pulses with high extinction ratio (null12 dB). The result is a high power, jitter-free RZ pulse source that is compact, inexpensive and power efficient.
Abstract:
A head of line blockage avoidance system for use with network systems that employ packets having an associated priority and a method of operation thereof. In one embodiment, the head of line blockage avoidance system includes: (1) m inputs, m numbering at least two, configured to receive the packets, (2) n packet first-in-first-out buffers (FIFOs), n numbering at least three, each of the packet FIFOs configured to receive at least one of the packets from the m inputs, (3) a priority summarizer configured to generate a priority summary of the packets within the m inputs and the n packet FIFOs, and (4) a scheduler configured to cause one of the n packet FIFOs to be queued for processing based on the priority summary.
Abstract:
A programmable resistive-capacitive filter circuit enabling on-chip digital control of the frequency response includes a switched resistive type voltage divider network where one of the resistors forms an element of an RC filter and wherein the voltage divider additionally provides a DC bias on an output terminal. One preferred embodiment of the invention is directed to a programmable bandpass filter including MOSFET type semiconductor devices which are utilized as switched resistive elements of the filter.
Abstract:
The invention provides a perceptually-based system for pattern retrieval and matching, suitable for use in a wide variety of information processing applications. An illustrative embodiment of the system uses a predetermined vocabulary comprising one or more dimensions to extract color and texture information from an information signal, e.g., an image, selected by a user. The system then generates a distance measure characterizing the relationship of the selected image to another image stored in a database, by applying a grammar, comprising a set of predetermined rules, to the color and texture information extracted from the selected image and corresponding color and texture information associated with the stored image. The vocabulary may include dimensions such as overall color, directionality and orientation, regularity and placement, color purity, and pattern complexity and heaviness. The rules in the grammar may include equal pattern, overall appearance, similar pattern, and dominant color and general impression, with each of the rules expressed as a logical combination of values generated for one or more of the dimensions. The distance measure may include separate color and texture metrics characterizing the similarity of the respective color and texture of the two images being compared. The invention is also applicable to other types of information signals, such as sequences of video frames.
Abstract:
A communications system includes N parallel communications channels connecting first and second devices. The N channels may include N-1 channels for carrying information symbols, and an Nth channel for facilitating deskewing and word framing. The first device may include an alignment symbol generator for generating alignment symbols on the Nth channel, and a word framing code generator for generating word framing codes on the Nth channel. The second device may include a deskewer for aligning received information symbols based upon the alignment symbols, and a word framer for determining word framing based upon the word framing codes. The word frame code generator in the first device or transmitter, and the word framer in the second device or receiver provide the desired feature of knowledge of where each word starts or begins. The start of each word may be determined in terms of a time and a corresponding one of the N-1 channels where the word starts. The word framing code generator may generate word framing codes comprising at least one predetermined word framing code. Alternately, the word framing code generator may generate word framing codes including at least one changeable word framing code based upon information symbols.