Abstract: In accordance with the invention, electronic packages comprising a layer of molded plastic on one side of an insulating substrate are provided with a surrogate layer on the side of the substrate opposite the molded plastic to reduce bending stress. The surrogate layer is preferably thin, has a high coefficient of thermal expansion and is resistant to high tensile stress. Advantageously, the surrogate layer is processed concurrently with the molding of the plastic. Preferred surrogate layers are low temperature thermoplastic sheets, such as acetal plastic sheets, that soften at the molding temperature sufficiently to bond to the substrate. Alternatively, they can be higher temperature rigid materials, such as glass fiber composites, bonded to the substrate with an adhesive layer that cures during molding.

Abstract: Techniques for encoding audio signals are disclosed wherein a left channel signal masking threshold and a right channel signal masking threshold may be advantageously adjusted. A given time block of a stereo audio signal comprises a left channel signal and a right channel signal, each of which are represented in a frequency domain by a first plurality of frequency partitions and a second plurality of frequency partitions, respectively. For a frequency partition from the first plurality of frequency partitions and a corresponding frequency partition from the second plurality of frequency partitions, a scheme first calculates a set of masking thresholds comprising the left channel masking threshold and the right channel masking threshold. Next, based upon the set of masking thresholds, the scheme calculates an adjusted left channel masking threshold and an adjusted right channel masking threshold.

Abstract: A device for transmitting radiation is provided. The device includes a glass optical waveguide having a core. A Bragg grating is at least partially formed within the core. Associated with the Bragg grating is a transmission spectrum that includes a band in which incident radiation is attenuated, the peak attenuation being at a wavelength .lambda.. The transmission spectrum of the Bragg grating is such that the full width at half maximum measured in transmission is greater than or equal to (1.5 nm/1558.5 nm) .lambda. and peak attenuation within the band is greater than or equal to 90% of full scale transmission. Attenuation exceeds 50% of the peak attenuation everywhere within the full width at half maximum of the transmission spectrum.

Abstract: A method and apparatus providing communications between mobile units and other communications devices, is disclosed wherein, in response to a request to call a mobile unit from an originating communications device, a paging signal is sent via a global communications network and received by a mobile unit. The paging signal contains caller and callee identification codes, which are decoded by the mobile unit. A paging response signal, in the form of a reverse call setup signal, is then transmitted from the mobile unit to the originating communications device. Transmission of the paging signal is preferably stopped when a correspondence condition exists such that the caller and callee identification codes of the paging signal correspond to the caller and caller identification codes of the paging response signal.

Abstract: In an apparatus and process for heating, e.g., a semiconductor wafer within a processing chamber, the wafer is exposed to a flux of electromagnetic radiation from lamps energized by alternating electric current. The surface temperature of the wafer is measured, and responsively, the radiation flux is controlled. The temperature measurement procedure includes collecting radiation propagating away from the wafer in a first probe, collecting radiation propagating away from the wafer and radiation from the lamps in a second probe, and detecting radiation collected in the respective probes. This procedure further involves deconvolving the multiphase ac component of the signal received from each probe, determining the linear functional relationship of the first probe signal as a function of the second probe signal resulting from time-variations of the energizing current, and using this linear functional relationship along with the signal data according to a mathematical expression to infer the temperature.

Abstract: A facility is provided in a telecommunications network which causes Digital Speech Interpolation (DSI) apparatus to transmit noise signals toward a destination if the level of the noise signals at least equals a predetermined threshold value, in which the predetermined threshold value is selected, in accord with an aspect of the invention, as a function of a type of telephone service subscribed to by the telephone station set involved in the associated telephone call.

Abstract: The total base-collector capacitance of a double-heterostructure bipolar transistor device is reduced by removing semiconductor material from the extrinsic regions and replacing the removed material with a relatively-low-dielectric-constant material, The base-collector capacitance is further reduced by using a composite subcollector structure that permits the extrinsic regions to be made thicker than the intrinsic region of the device.

Abstract: Complementary circuits with inorganic n-channel thin film transistors (TFTs) and organic p-channel TFTs can exhibit advantageous properties, without being subject to some of the drawbacks of prior art complimentary inorganic TFTs or complementary organic TFTs. In preferred embodiments of the invention, the n-channel inorganic TFTs have an amorphous Si active layer, and the p-channel organic TFTs have .DELTA.-hexathienylene (.alpha.-6T) active layer. Complementary inverters according to the invention are disclosed, as is an exemplary processing sequence that can be used to manufacture integrated complementary inverters and other complementary circuits according to the invention.

Abstract: A remote control unit for use with an in-home audio player adapted to play pre-recorded music stored on a semiconductor music chip storage medium. In accordance with one preferred embodiment of the invention, the remote unit is a battery powered, hand held device which enables customized music selection to be made at the audio player from a distant position. The remote control unit includes an LCD display, a series of control buttons and an infrared communication interface for transmitting and receiving data from the audio player. A docking port is included in the audio player for mating with the remote control in order to download general information stored in memory of the audio player regarding each of the music chips which it has loaded. A processor within the remote control guides the user through a menu driven software routine for making music selection at the player. A user scrolls through the various menus by use of a navigation pointer.

Abstract: A pay per use system for of the unauthorized use of computer software. An encryption program encodes original software to produce secured software. The encoding is accomplished by using cryptographic techniques. In order to use the software, a user must call a telephone number to receive the cryptographic keys necessary to decrypt the secured software. Thus, users must pay for each use of the secured software. The system allows software developers to freely distribute the secured software. Copies of the secured software may be freely made, because payment is based on each use of the software not on each copy of the software.

Abstract: A parallel ring network is restorable upon sensing a failure of a transmission media. A central transmitter is coupled to one end of a first transmission medium. A central receiver is coupled to one end of a second transmission medium. A central sensor senses a transmission media failure centrally and provides a central alarm. In response to the central alarm, the central receiver is coupled to another end of the first transmission medium and the central transmitter is coupled to another end of the second transmission medium. At least one local station has a local receiver, a local transmitter, a local sensor for sensing a transmission media failure locally and providing a local alarm, and a local switch. In response to the local alarm, the local switch moves from a first position to a second position. When the local switch is in the first position, the local transmitter is coupled to the second transmission medium and the local receiver is coupled to the first transmission medium.

Abstract: A method of increasing the testability of sequential circuit designs with use of a clock transformation technique. Circuit states which are difficult to reach, but are nonetheless required to detect at least one fault of the circuit, are automatically identified. In accordance with one illustrative embodiment, estimations of joint line probabilities are compared with a preselected threshold value to identify hard-to-reach states. Then, commonly clocked flip-flops which must be simultaneously assigned values in order to reach the identified states are partitioned into independently clocked groups of flip-flops. In this manner, hard-to-reach circuit states are transformed into easy-to-reach states, which, in turn, results in transforming difficult-to-detect faults into easy-to-detect faults.

Abstract: The present invention provides an acoustic cell for determining the composition of gas mixtures. The acoustic gas composition analysis cell has transducers isolated from the cell body by a metal housing. A sound-absorbing sleeve around the body of the transducer increases the signal-to-noise ratio to at least 4:1. Additionally, the transducers employed in the acoustic cell operate in the kilohertz range, reducing attenuation in the gas mixture being analyzed. The cell body employs vacuum seals which permit the use of the cell in line with vacuum equipment.

Abstract: A holder for a plurality of fibers has a top wall, a bottom wall, and first and second side walls. The top wall is preferably releasably hinged to one of the two side walls so that the plurality of fibers may be contained within the holder. The fibers are maintained in a certain order within the holder by selecting the spacing between the two side walls to be greater than the outer diameter of the cables but less than twice the outer diameter of the cables. In this manner, two adjacent fibers cannot switch places with each other within the holder. The holder may have one or more intermediate walls positioned between the two side walls to divide the plurality of fibers into two or more groups. By maintaining the fibers in a fixed certain order, the fibers cannot become intertwined with each other and the chance that the fibers become bent is reduced. Since the chance that the fibers become bent is reduced, the risk of fiber breakage or signal loss is also reduced.

Abstract: Method and apparatus for preparing a message stream of symbols for wireless transmission by pre-coding it through convolution with a characteristic "signature" of predetermined symbols identifying a particular user of the message system. The time duration of the signature should exceed the inter-symbol interval of the message stream in order to reduce the likelihood of error caused by fading in the transmission channel.

Abstract: A method and apparatus is provided for comparing a first input voltage to a second input voltage. In one embodiment of the invention, a first input voltage is transformed into a first current flowing through a first transistor and a second transistor. A second input voltage is transformed into a second current flowing through the first transistor while the first current continues flowing through the second transistor. A difference current is developed which represents the difference between the first current and the second current. An indicator signal is generated which indicates the larger of the first and second input voltages based on the value of the difference current.

Abstract: A Dynamic Time/Frequency Warping (DTFW) technique is disclosed for speaker verification, speech recognition and channel normalization, among other uses. The DTFW technique utilities best path dynamic programming methods using a 3-dimensional time frequency array representing the spectral differences between a test utterance (the utterance being analyzed) and a reference utterance (template). The array is created by summing the squares of the differences of each feature in each frame of the template with each feature in each frame of the utterance in question. Dynamic programming techniques are then used to find the minimal distance path matching the test utterance and the template so as to optimize the time and frequency warping paths.

Abstract: An optical coupler is disclosed which utilizes a pair of polarization selective filters to multiplex a message signal (of perhaps random polarization) with a pair of polarized pump signals onto a common signal path. The filters may be disposed within optical elements (e.g., cubes) which may be physically joined together to form a bulk optic device. An optical isolator may then be directly attached to the output of the bulk polarization independent optical coupler. The positioning of the pump signal inputs with respect to the filters provides either a co-propagating scheme or counter-propagating scheme.

Abstract: A generalized leaky bucket mechanism allowing multiple burst sizes and drain rates. The generalized leaky bucket includes multiple token pool sizes and drain rates, wherein the leaky bucket gradually steps up to larger token pool sizes and steps down as soon as user bursts utilize the increased number of tokens. This allows bursts of various sizes with frequencies which decrease with the burst size. Control of when to step up to higher burst sizes is accomplished through simple trigger conditions which operate to selectively increment the token pool count of the leaky bucket at these times.

Abstract: A portion of a surface of a sample body is arranged to receive an incident optical beam having an optical intensity I.sub.0. On an opposing surface of the sample body is located an optical detector which senses the intensity I of the resulting optical radiation emerging from the opposing surface of the sample body. In order to measure the thickness t of the sample body, a thickness gauge is located either at another portion of the surface of the sample body or on the optical detector.