Abstract: A receiver for receiving wireless packetized audio signals having packet headers, and packet payloads including encoded audio signals is provided. The receiver includes an audio decoder for decoding the encoded audio signals into digital audio signals, an audio error detector for detecting impulsive noise in the digital audio signals caused by corrupted payload packets, and a digital signal restoration unit for removing the impulsive noise from the digital audio signals. Further, a method of noise reduction includes the steps of receiving radio frequency packetized audio signals having packet headers, and packet payloads including encoded audio signals and demodulating the RF signals. The method further includes decoding the encoded audio signals into digital audio signals and detecting impulsive noise in the digital audio signals caused by corrupted payload packets. The method further includes removing the impulsive noise by reconstructing the corrupted digital audio signal.

Abstract: Techniques for monitoring optical transmissions between an optical transmitter and an optical receiver are described. A transmitter monitor is coupled to an optical transmitter and detects light, such as reflected light, conducted into the transmitter by an optical cable conveying light between the transmitter and the receiver. The transmitter monitor produces a signal providing information about the light conducted into the transmitter and adjustments are made to the transmitter operation based on the signal. A receiver monitor coupled to an optical receiver detects light conducted into the receiver by the optical cable. The receiver monitor produces a receiver monitor signal providing information about the light and adjustments are made to the receiver operation based on the signal. In addition, an optical signal is sent to the transmitter based on the receiver monitor signal, and the optical signal is used by the transmitter monitor to direct adjustments to the transmitter operation.

Abstract: Distortion and crosstalk that occurs when operating optical amplifiers in saturation is substantially reduced by passively compensating for gain variations caused by changes in input power to the optical amplifiers. More specifically, in an optical communication system having one or more optical amplifiers, a “reservoir” optical channel is supplied in addition to the other traffic-carrying optical channels. The wavelength of the reservoir channel is selected such that the power level of the reservoir channel varies in response to changes in power levels of the traffic-carrying channels. Because gain variations are typically highest around the gain peak region in an optical amplifier's gain bandwidth, the reservoir channel in one exemplary embodiment is assigned a wavelength around the gain peak region.

Abstract: In a multi-processor data processing system, apparatus and a method for ensuring continued operation without loss of critical data. The critical disk data of a processor is duplicated on duplex disks of a separate disk platform. The updating of the disk platform information is accomplished automatically so that it is transparent to a user or programmer of the processor. Advantageously, the three-way mirroring of the data (processor disk and two disk platform disks), provides very high reliability.

Abstract: A method and apparatus for transmitting a modulated optical signal includes a continuous source of light, a first optical modulator for generating an optical pulse stream in response to a radio frequency (RF) driving signal and a DC bias signal, and a second modulator for modulating the optical pulse stream with an electrical data signal. A processor dithers the phase of the RF driving signal using a first dither signal and the level of the DC bias signal using a second dither signal. The processor detects the first and/or second dither signals in the modulated optical signal and adjusts the phase of the RF driving signal and/or level of the DC bias signal to null the detected first and/or second dither signal.

Abstract: A stack of two or more birefringent crystals having complimentary properties is arranged to have zero net beam walk-off at off-normal incidence and a finite free-spectral range. In another embodiment, the birefringent crystal materials are selected to provide reduced temperature dependence. The result is an optically and mechanically stable composite birefringent crystal unit. A variety of folded birefringent filters are implemented using the composite birefringent crystal.

Abstract: The operation of software carrying out a computer program is monitored for determining which blocks of code are being run and which are inactive. Each block of code being monitored has a software probe inserted at the beginning of the block for detection and identification purposes. In one embodiment, the software probe inserted in the block of code is automatically increment by 1 to indicate that the block has been accessed. The extent of use, or activity, of each block of code is recorded and presented in graphic form on a video display. In a first mode of operation, the times at which a selected block of code is accessed within a given time period is displayed along a horizontal axis and the number of times of access at each time it occurs is represented along a vertical axis in bar graph form.

Abstract: In a system and method for the collection of alphanumeric data from Customer Premise Equipment (CPE) at the behest of an enhanced service provider (such as a utility company) requesting said data, a CPE transmits the data in the form of a synthesized voice signal, obviating the need for modems. The invention is useful for applications such as Automatic Meter Reading (AMR) and Home and Business Electronic Systems (HBES). The targeted CPE in such a system, after being connected to a remote applications server via a telephone call including “suppressed ringing,” converts data collected to a standard voice signal via a voice synthesizer and transmits the voice signal to the applications server. The applications server performs a speech-to-text conversion to place the data back into its alphanumeric form.

Abstract: A system and method to convert a CIF compressed video to a QCIF video bitstream provides compatibility between the various digital video sources and application uses. A coding mode and a motion vector for a macroblock in a QCIF video sequence are selected from those of a corresponding CIF video sequence without motion estimation.

Abstract: A plurality of user personas relating to various criteria for performing tasks for a user is created. A policy manager for various criteria, which apply to the user regardless of any one persona among the plurality of personas, including sub-personas thereof is established. At least one user persona from among the plurality of user personas is selected. A computer network searching task based on the policy manager and the at least one user persona selected from among the plurality of user personas is performed. Results of the computer network searching task for the user in at least a two dimensional graphical representation are presented.

Abstract: The linearity and noise performance of an inexpensive optical signal source are improved using either feedback or feedforward correction techniques. In a feedback embodiment of the invention, a modulation signal, such as a broadband analog CATV signal, is applied to the optical source along with an error signal. The error signal is generated in a feedback path using a high-speed photodiode to detect a portion of the output optical signal generated by the optical source. A delay compensation filter in the feedback path corrects for variations in error signal delay as a function of frequency, such that source nonlinearity and noise may be corrected over a broad bandwidth. In a feedforward embodiment of the invention, an error signal generated from a portion of the output of the optical source is converted to a frequency band outside of the modulation signal bandwidth before being applied to an input of the optical source.

Abstract: A method and apparatus for applying an electrical signal as a first of two inputs to a logic element, manipulating the output of the logic element such that the logic element produces a resulting electrical signal that logically transitions only when the input signal has associated with it a predetermined logic state, shaping the resulting electrical signal according to a desired RZ optical signal, amplifying the shaped electrical signal such that a maximum and a minimum signal level of the shaped electrical signal correspond to the adjacent optical power transfer zeroes of an optical modulator, and applying the amplified electrical signal as a driver input to the optical modulator.

Abstract: A method for establishing a communications path between a source node and destination node. The method includes defining a first group of network elements (NEs) suitable for use in the communications path, contemporaneously determining available resources within each of the NEs of the first group of NEs, and contemporaneously reserving those available resources appropriate to establish the communications path. The reserved resources sufficient to establish the communications path are selected, while those reserved resources not selected are released. In the absence of available resources sufficient to establish the communications path, the method is repeated using a second group of NEs suitable for establishing the communications path.

Abstract: The present invention provides a method of testing micro-electrical mechanical mirrors including simultaneously applying a voltage to each of a plurality of such mirrors to tilt each of the plurality to a deflection angle, and simultaneously deflecting a beam from each of the plurality using an interferometer to simultaneously determine an accuracy of the deflection angle of each of the plurality. In addition, a method of manufacturing micro-electrical mechanical mirrors is also disclosed.

Abstract: A method of producing a nanofeature or a nanocircuit on a substrate, including soaking a stamp having a nanopattern thereon in an ink to allow the ink to absorb into the stamp and provide an inked stamp, and applying the inked stamp against a substrate to transfer an ink pattern onto the substrate, wherein the ink within the inked stamp replenishes the pattern in response to the transfer of the ink pattern.

Abstract: The present invention provides a process for forming electrical contacts to a molecular layer in a nanoscale device, the nanoscale device, and a method of manufacturing an integrated circuit comprise such devices. The process includes coating a surface of a stamp with a metal layer and forming an attached layer of anchored molecules by coupling first ends of the anchored molecules to a conductive or semiconductive substrate. The process also includes placing the metal layer in contact with the attached layer of anchored molecules such that the metal layer chemically bonds to free ends of the anchored molecules. The resulting devices produced have superior reliability as compared to conventional prepared devices.

Abstract: In a mobile radio network such as the Universal Mobile Telephone System, for handover or relocation of control of a mobile from a serving RNC 22 to a target RNC 24, the TRNC 24 sends a request to the SRNC 22 over the Iur link 27, and the SRNC 22 returns frame timing information. The TRNC 24 synchronizes the user plane with the SRNC for this uplink, so that both controllers are able to send the same packets in synchronizm. The core network (10) can suppress the duplicated packet.

Abstract: A radio transmission link between at least one radio transmission device is monitored and at least one radio reception device. Radio transmission links between at least one transmission antenna and one reception antenna are monitored for faults. At least one radio reception device is tuned to the transmission frequency of at least one radio transmission device. The at least one radio transmission device then transmits, during a predetermined time period, a predetermined test signal which is recorded, evaluated and stored as a reference signal in the at least one radio reception device during a predetermined time period. At the start of a test phase, at least one radio transmission device transmits the predetermined test signal. The test signal is compared with the stored reference signal, and an error signal is produced if the comparison result shows that the test signal has changed beyond a predetermined extent with respect to the stored reference signal.

Abstract: A mobile telephone system includes a base station which establishes a link with a selected mobile station. The received signal from the mobile station will include a noise component as well as a possible interference component from another mobile station operating at the same frequency in another cell. The base station has a trellis based equalization system which operates on the assumption that the received signal includes components which have a predominantly Gaussian characteristic. A switch controller determines when the interference component (which is non-gaussian) in the received signal becomes a dominant component and operates to switch a spatio-temporal filter into the circuit instead of the trellis based equalization system, to improve the bit error rate performance.

Abstract: A shutter switch that may be fabricated using a single wafer, which alleviates the alignment problem associated with a two-piece prior art design. The switch has a movable mirror that is designed for in-plane motion. The mirror is connected to a drive shaft that can be moved, e.g., using one or more serpentine springs and a comb drive actuator. During operation, the mirror is in either one of two terminal positions. The mirror moves between the terminal positions in response to a voltage applied to the actuator. The springs and actuator are designed such that small voltage variations around the voltage values corresponding to the terminal positions do not substantially displace the mirror from those positions. As a result, any electrostatic charge accumulation will not result in significant drifting of the mirror. Multiple shutter switches may be arrayed in a single integrated structure.