Abstract: A direct conversion transmitter comprising two local oscillators, an in-phase and quadrature modulating signal and in-phase and quadrature modulators, adds a leakage detector and corrective algorithm with one or more digital to analog converters to generate a corrective signal. The corrective signal corrects for, minimizes, and suppresses local oscillator carrier leakage into the transmitted signal. In accordance with the invention, direct up transmitter carrier leakage is automatically measured at regular intervals during the transmit cycle. A DC correction, or a correction waveform as a function of time, is input to both the “in-phase” and “quadrature” modulators at the baseband input. The two correction signals are tuned according to a minimization algorithm to achieve the lowest possible carrier component in the spectral output of the transmitter at its ambient operating conditions and present power output level.

Abstract: A method and apparatus for determining if an optical input signals has been interrupted and responsively replacing an interrupted optical input signal with a replacement optical signal having a similar optical profile (e.g., such as a loopback between OADMs within a backbone network), thereby insuring that transient-induced high speed optical amplifier adjustments are avoided.

Abstract: A method and apparatus for measuring optical power or insertion loss within an optical cross-connect system utilizing a plurality of parallel light beams sampled at switch fabric input and output portions via imaging devices.

Abstract: A telephone interface (110) that supports a first and a second conference call service is provided in a telephone-capable apparatus (102). An input device (122) is further provided, allowing a conference call conferee to provide participation status data to a controller (116, 118) of the apparatus. The controller provides a message to a switch (104), responsive to the participation status data, instructing the switch to provide the apparatus with communication resources commensurate with the participation status data. When the participation status data indicates that the conferee is a speaking and listening conferee, the message instructs the switch to provide resources sufficient to support the first conference call service and a send-only version of the second conference call service.

Abstract: An optical system for monitoring or imaging a sample includes a probe, an optical splitter or circulator, and an optical detector. The probe includes an optical fiber and a GRIN fiber-size lens fused to one end of the fiber. The optical splitter or circulator receives light from a source and directs a portion of the received light to the fiber. The optical detector is coupled to receive a portion of light collected from the sample by the GRIN fiber-size lens and is configured determine a characteristic of the sample from the received light.

Abstract: In accordance with the invention, a train of RZ or CSRZ pulses is produced by passing phase modulated laser light through a delay interferometer. The parameters of the phase modulation and the delay interferometer are calculated from the desired pulse train characteristics (e.g. repetition rate, RZ or CSRZ, duty cycle). A directly modulated CW laser, or a CW laser followed by a phase modulator, produces the constant amplitude, phase modulated light. The phase modulated signal is split into two paths. One signal path is delayed with respect to the other by the calculated delay. The signals are recombined in an optical coupler to produce an RZ pulse train and/or a CSRZ pulse train.

Abstract: A method for querying electronic data. The query method comprises creating wavelet-coefficient synopses of the electronic data and then querying the synopses in the wavelet-coefficient domain to obtain a wavelet-coefficient query result. The wavelet-coefficient query result is then rendered to provide an approximate result.

Abstract: A method is presented for efficiently utilizing network resources while routing voice communications over a packet-based data network with specified minimum quality of service requirements, where greater network resources are required to ensure higher quality of service parameters. A dial code can be entered by a user to specify an appropriate quality of service. If the dial code is valid, the call is routed with the specified quality of service. If the dial code is not valid, the call is routed with default minimum quality of service parameters. Also, a line may be associated with overriding minimum quality of service parameters, whereby all calls directed to such a line are automatically upgraded, if necessary, to conform to the overriding minimum quality of service parameters.

Abstract: A device which stores frequently used data items in a retrieval list for easy retrieval and use. An example is a telephone operative to identify frequently-dialed telephone numbers and prompt a user to store frequently-dialed numbers in a speed-dial list. When a number is entered in the telephone, the number is compared with a log of stored numbers. Each stored number has an associated usage frequency. If the entered number is present in the log, the usage frequency of the entered number is updated. If the entered number is not present, the entered number is stored along with an initial usage frequency. The usage frequency of the number is compared against a predetermined criterion, and if the criterion is met the user is prompted to store the entered number in an empty space in the speed-dial list, or to replace an already existing entry in the speed-dial list with the entered number. Any of numerous alternatives may be chosen for prompting of the user and storage of the entered number.

Abstract: In an intersubband light emitter, at least two injection/relaxation (I/R) regions contiguous with the same RT region have different doping levels. Preferably, one I/R region has a doping level that is at least 100 times lower than that of the other I/R region. In one embodiment, one I/R region is undoped, whereas the other I/R region is doped.

Abstract: An apparatus for enhancing intelligibility of a voice signal in a noisy environment includes a first noise estimator which estimates a far-end noise component from the far-end signal, and a second noise estimator which estimates a near-end noise component from the near-end signal. A noise reduction calculator determines a noise reduction gain from the estimated far-end noise, and an echo gain calculator determines an echo control gain. A master gain calculator combines both the echo control gain and the noise control gain into a master gain which is applied to the far-end signal. A comfort noise generator applies the pre-set minimum threshold of the master gain and constantly matches the spectrum of the far-end noise to synthesize a background noise for selectively mixing onto the far-end signal when echo is determined. Echo is determined based on a comparison of the near-end signal and the far-end signal spectra and by compensating the total gain applied.

Abstract: A method and apparatus for performing automatic speech recognition (ASR) in a distributed ASR system for use over a wireless channel takes advantage of probabilistic information concerning the likelihood that a given, portion of the data has been accurately decoded to a particular value. The probability of error in each feature in a transmitted feature set is employed to improve speech recognition performance under adverse channel conditions. Bit error probabilities for each of the bits which are used to encode a given ASR feature are used to compute the confidence level that the system may have in the decoded value of that feature. Features that have been corrupted with high probability are advantageously either not used or are weighted less in the acoustic distance computation performed by the speech recognizer.

Abstract: A power control method for reverse links used in soft handoff mode between a mobile and base stations of a CDMA wireless communication network. Each of the base stations computes a setpoint based on the quality of received frames. The lowest setpoint value is then used as a threshold for inner loop operation causing at least one of the reverse links to convey information in compliance with a target FER set by the network.

Abstract: A spatial median filter determines a median of a plurality of values by dividing the plurality of values into a plurality of groups of values. The values in each of the groups are sorted to determine its median. Then, the medians of the plurality of groups are fully sorted. Certain of the sorted values are eliminated from prescribed ones of the groups in accordance with prescribed criteria based on the number of values in the group and the median value of the group values. The remaining values are sorted to determine the median of the plurality of values.

Abstract: A vertically expandable keyboard includes keys arranged in a plurality of rows. The keyboard has a retracted configuration wherein the rows are generally coplanar with each other and an extended configuration wherein at least some of the rows of keys in the home position are extended from the retracted configuration such that the rows are not coplanar with other rows. In the extended configuration, the rows can be sequentially tiered such that each row is higher than the preceding row moving from the front row to the back row. The keyboard includes lifters for lifting the rows of keys to the extended configuration. The keyboard can be part of an electronic device such as a portable computer.

Abstract: Apparatus and method for allowing fine adjustment of a diffraction grating within an optical wavelength-division multiplexing (WDM) device and for maintaining the grating in near-littrow alignment (i.e., to within an accuracy of +/−0.003 degrees) over the device's operating temperature range. Precise alignment is maintained by use of a 0.3 PPM/° C. “super invar” material in a wedge-shaped grating mount to eliminate an angular shift of the grating over typical operating temperatures. The wedge-shaped grating mount and thereby the orientation of the surface of the grating are adjusted precisely and maintained in position over the operating temperatures via a dual flexure structure wherein four precision adjustment screws with jeweled contact tips are tightened to achieve the desired orientation and stiffen the structure and then locked via locking nuts to prevent slippage.

Abstract: Echoes caused by discontinuities in a telecommunications transmission lines cause double talk which cause divergence problems with echo cancellers. Divergence problems in echo cancellers cause considerable problems in interactive caller response systems, they cause less problems if all parties to a call are human. One of the biggest problems is the effect of the echoes on automatic speech recognition systems. The echo canceller method and system presented cancels echoes to reduce their interference with ASR and yet provides stability in the presence of double talk.

Abstract: The beams between a MEMS device and an input source or an output, e.g., a fiber bundle, are caused to be closer to each other at the MEMS device than at the fiber bundle. This can be achieved in a variety ways. This may be achieved a) when each fiber is associated with a respective micro lens of a micro lens array, by insuring that there is a different distance between the centers of adjacent micro lenses than there is for the centers of their corresponding adjacent fibers, b) when the fibers are terminated by collimators, the direction of the collimators is adjusted to point the beams in a converging manner and c) by employing an optical system that changes the direction of various ones of the beams may be interposed between a) the fiber bundle and b) the corresponding MEMS device.

Abstract: The performance of wireless devices is improved using methods and devices which comprise novel SPEED and NOISE metrics. The SPEED metric is generated from a mean value of a differential signal while the NOISE metric is generated from a variance value of a differential signal. The generation of both metrics assumes the use of a limited number of symbols used to generate the mean and variance values. One example of a signal used to generate the metrics comprises the 14 synchronization symbols which make up part of an IS-136 standard signal. The SPEED metric was discovered to comprise a value which is equal to the magnitude of the mean value of the differential signal while the NOISE metric was discovered to comprise a value which is approximately equal to twice the variance of noise in a received baseband signal, while at the same time being independent of the speed at which an object, such as a wireless device, moves.

Abstract: Disclosed is a method and an apparatus for enhancing existing caching systems to better support the live broadcast of streaming multimedia over the Internet and other public network systems. The apparatus includes the use of helper servers in the network for supporting high quality live streaming multimedia (SM) broadcasts. The helper servers (HS), also referred to as helpers, are each positioned in the network to be close to some number of clients. Client requests for live SM broadcast objects are re-routed from the content server to the local HS to be serviced therefrom. Servicing requests from the local HS is advantageous in that the requests are not required to be serviced from the content server as separate unicast datastreams thereby reducing network congestion problems. In addition to servicing requests locally, each HS allocates and maintains PH buffers which operate as a form of dynamic cache to further reduce the playback delay at a client.