Showing papers by "Agilent Technologies published in 2001"

Expression profiling using microarrays fabricated by an ink-jet oligonucleotide synthesizer.

Abstract: We describe a flexible system for gene expression profiling using arrays of tens of thousands of oligonucleotides synthesized in situ by an ink-jet printing method employing standard phosphoramidite chemistry. We have characterized the dependence of hybridization specificity and sensitivity on parameters including oligonucleotide length, hybridization stringency, sequence identity, sample abundance, and sample preparation method. We find that 60-mer oligonucleotides reliably detect transcript ratios at one copy per cell in complex biological samples, and that ink-jet arrays are compatible with several different sample amplification and labeling techniques. Furthermore, results using only a single carefully selected oligonucleotide per gene correlate closely with those obtained using complementary DNA (cDNA) arrays. Most of the genes for which measurements differ are members of gene families that can only be distinguished by oligonucleotides. Because different oligonucleotide sequences can be specified for each array, we anticipate that ink-jet oligonucleotide array technology will be useful in a wide variety of DNA microarray applications.

Image classification for content-based indexing

Abstract: Grouping images into (semantically) meaningful categories using low-level visual features is a challenging and important problem in content-based image retrieval. Using binary Bayesian classifiers, we attempt to capture high-level concepts from low-level image features under the constraint that the test image does belong to one of the classes. Specifically, we consider the hierarchical classification of vacation images; at the highest level, images are classified as indoor or outdoor; outdoor images are further classified as city or landscape; finally, a subset of landscape images is classified into sunset, forest, and mountain classes. We demonstrate that a small vector quantizer (whose optimal size is selected using a modified MDL criterion) can be used to model the class-conditional densities of the features, required by the Bayesian methodology. The classifiers have been designed and evaluated on a database of 6931 vacation photographs. Our system achieved a classification accuracy of 90.5% for indoor/outdoor, 95.3% for city/landscape, 96.6% for sunset/forest and mountain, and 96% for forest/mountain classification problems. We further develop a learning method to incrementally train the classifiers as additional data become available. We also show preliminary results for feature reduction using clustering techniques. Our goal is to combine multiple two-class classifiers into a single hierarchical classifier.

Imaging the body with diffuse optical tomography

Abstract: Diffuse optical tomography (DOT) is an ongoing medical imaging modality in which tissue is illuminated by near-infrared light from an array of sources, the multiply-scattered light which emerges is observed with an array of detectors, and then a model of the propagation physics is used to infer the localized optical properties of the illuminated tissue. The three primary absorbers at these wavelengths, water and both oxygenated and deoxygenated hemoglobin, all have relatively weak absorption. This fortuitous fact provides a spectral window through which we can attempt to localize absorption (primarily by the two forms of hemoglobin) and scattering in the tissue. The most important current applications of DOT are detecting tumors in the breast and imaging the brain. We introduce the basic idea of DOT and review the history of optical methods in medicine as relevant to the development of DOT. We then detail the concept of DOT, including a review of the tissue's optical properties, modes of operation for DOT, and the challenges which the development of DOT must overcome. The basics of modelling the DOT forward problem and some critical issues among the numerous implementations that have been investigated for the DOT inverse problem, with an emphasis on signal processing. We summarize with some specific results as examples of the current state of DOT research.

Thin film bulk wave acoustic resonators (FBAR) for wireless applications

Abstract: For some time, FBAR technology has lagged behind ceramic technology and surface acoustic wave resonator (SAW) technology for commercial applications. There were several technologies that had to be developed before FBAR technology became viable for rf filters. First, a process is needed that can make the resonators manufacturable, robust and repeatable. Second, maximizing the coupling coefficient, k/sub t//sup 2/ and the Q of the resonator (k/sub t//sup 2/ Q product) is necessary. Another technology needed is a method to eliminate ripple (or "suck out") associated with lateral mode excitation. Lastly, a method is needed for maintaining a uniform thickness (for frequency control and a means to target frequency to within +-0.03%). If one overcomes these sets of hurdles, the rewards are high. The Quality factor, Q, inherent in these structures is impressive (over 2500) and the intrinsic k/sub t//sup 2/ has been inferred to be close to the theoretical maximum of 6.5%. The k/sub t//sup 2/ Q product (Figure of Merit for FBAR filters) have been as high as 100 for our devices. These two properties can be combined in a filter to achieve low pass band insertion loss and extremely sharp skirts. One intrinsic advantage of FBAR over SAW technology is the ability to handle input power in excess of 4 Watts. Resistance to Electrical Static Discharge (ESD) is another desirable property of FBAR devices. Finally, FBAR technology is intrinsically a "low temperature" process technology-compatible with semiconductor technology. This implies future integration of FBARs with semiconductor circuits.

An extended Doherty amplifier with high efficiency over a wide power range

Abstract: An extension of the Doherty amplifier, which maintains high efficiency over a wide range of output power (>6 dB), is presented in this paper. This extended Doherty amplifier is demonstrated experimentally with InGaP/GaAs heterojunction bipolar transistors at 950 MHz. Power-added efficiency (PAE) of 46% is measured at P/sub 1dB/ of 27.5 dBm and 45% is measured at 9 dB backed off from P/sub 1dB/. Additionally, PAE of at least 39% is maintained for over an output power range of 12 dB backed off from P/sub 1dB/. This is an improvement over the classical Doherty amplifier, where high efficiency is typically obtained up to 5-6 dB backed off from P/sub 1dB/. Compared to a single transistor class-B amplifier with similar gain and P/sub 1dB/, the extended Doherty amplifier has PAE 2.6 /spl times/ higher at 10 dB back off and 3 /spl times/ higher at 20 dB back off from P/sub 1dB/. Under different bias and output matching conditions, the amplifier was also evaluated with CDMA signals. At the highest measured power of 25 dBm, the extended Doherty amplifier achieves a PAE of 45% with an adjacent channel power ratio of -42 dBc. Generalized design equations are also derived and the consequences of finite device output impedance on amplifier gain and linearity are explored.

Domain specific knowledge-based metasearch system and methods of using

Abstract: A system and method for performing domain-specific knowledge based metasearches. A metasearch engine is provided for accessing a searching text-based documents using generic search engines while simultaneously being able to access publication based databases and sequence databases as well as in-house proprietary databases and any database capable of being interfaced with a web interface so as to produce search results in text format. A data mining module is also provided for organizing raw data obtained by unsupervised clustering, simple relevance ranking, and categorization, all of which are done independently of one another. The system is capable of storing previous search data for use in query refinement or subsequent searches based upon the stored data. A search results collection browser may be provided for analyzing current browsing patterns of the user for developing weighting factors to be used in ordering the results of future searches.

Single-unit neural recording with active microelectrode arrays

Abstract: Discusses the single-unit recording characteristics of microelectrode arrays containing on-chip signal processing circuitry. Probes buffered using on-chip unity-gain operational amplifiers provide an output resistance of 200 /spl Omega/ with an input-referred noise of 11-/spl mu/V root-mean-square (rms) (100 Hz-10 kHz). Simultaneous in vivo recordings from single neurons using buffered and unbuffered (passive) iridium recording sites separated by less than 20 /spl mu/m have shown that the use of on-chip circuitry does not significantly degrade system noise. Single-unit neural activity has also been studied using probes containing closed-loop preamplifiers having a voltage gain of 40 dB and a bandwidth of 13 kHz, and several input de-baseline stabilization techniques have been evaluated. Low-noise in vivo recordings with a multiplexed probe have been demonstrated for the first time using an external asymmetrical clock running at 200 kHz. The multiplexed system adds less than 8-/spl mu/V rms of noise to the recorded signals, suppressing the 5-V clock transitions to less than 2 ppm.

Optical pseudo trackball controls the operation of an appliance or machine

Abstract: An optical fingertip tracker, which may be a pseudo trackball, responds to the motion of the texture on one of the user's digits pressed against an image input aperture to produce motion signals processed within an appliance to be controlled. The appliance may have a minimal GUI, such as an LCD display having only a modest number of low resolution pixel locations and/or preestablished characters or icons. An appliance control parameter is set or adjusted in response to translation of the fingertip along a particular axis. E.g., to enter a parameter value (volume) a changing bar graph can be displayed. The display might even be omitted; to set the tone control of an audio appliance it can be sufficient to simply adjust the tone until the result is as desired. A numeric display of control parameter digits may be desirable, as when moving the fingertip tunes a receiver. There can be several particular axes along which fingertip movement changes an associated appliance control parameter. Other appliances can include character recognition of input characters traced by the fingertip. A pressure sensitive switch coupled to the fingertip tracker can serve as a delimiting mechanism useful in ratification of interpreted results and in editing strings that have been input. Excursions is a loss-of-correlation signal can be detected and interpreted as tapping the image input aperture with the fingertip. Such “taps” and “double taps” can be defined, and have selected meanings associated therewith that may be used in conjunction with, or in place of, the pressure sensitive switch.

Method and apparatus for calibrating a multiport test system for measurement of a dut

Abstract: According to one embodiment of the invention, there is provided a method of calibrating an N-port multiport test system for measurement of a DUT. The method consists of coupling each port of an N-port automatic calibration device to a respective port of the N-port multiport test system, and presenting three reflection standards with the automatic calibration device to each port of the N-port multiport test system. The method also consists of providing with the automatic calibration device, N−1 through conditions of a possible N(N−1)/2 possible through conditions, between corresponding ports of the N-port multiport test system, and making measurements with the N-port multiport test system of the three reflection standards at each port and the N−1 through conditions between the corresponding ports. The method further consists of determining all of systematic error coefficients for all of the ports of N-port multiport test system.

A controlled experiment for evaluating quality guidelines on the maintainability of object-oriented designs

Abstract: The paper presents a controlled experiment, focusing on the impact of applying quality design principles such as the ones provided by P. Coad and E. Yourdon (1991) on the maintainability of object oriented designs. Results, which repeat the findings of a previous study, strongly suggest that such design principles have a beneficial effect on the maintainability of object oriented designs. It is argued that object oriented designs are sensitive to poor design practices because the cognitive complexity introduced becomes increasingly unmanageable. However, as our ability to generalize these results is limited, they should be considered as preliminary, i.e., it is very likely that they can only be generalized to programmers with little object oriented training and programming experience. Such programmers can, however, be commonly found on maintenance projects. As well as additional research, external replications of this study are required to confirm the results and achieve confidence in these findings.

Method and apparatus for measuring spectral content of LED light source and control thereof

Abstract: Solid state illumination using closed loop spectral control. Light emitting diodes producing different colors (110, 120, 130) are mounted in close proximity to photosensors (150). Spectral content of the light emitting diodes is measured by the photosensors (150), and these measurements used to adjust light emitting diode currents to achieve the desired spectral characteristics.

Ultra-miniature high-Q filters and duplexers using FBAR technology

Abstract: An ultra-miniature PCS duplexer uses thin-film bulk wave acoustic resonator (FBAR) technology. FBAR resonators are made using aluminum nitride for the piezoelectric material and silicon as the substrate. It has better than -52 dB rejection for the receive (Rx) filter in the transmit (Tx) band and pass-band insertion losses are on the order of 2 dB (Tx) and 3 dB (Rx). Performance is comparable to that of much larger ceramic duplexers.

Preparation of biopolymer arrays

Abstract: A method and apparatus for fabricating an array of biopolymers on a substrate using a biopolymer or biomonomer fluid, and using a fluid dispensing head. The head has at least one jet which can dispense droplets onto a substrate, the jet including a chamber with an orifice, and including an ejector which, when activated, causes a droplet to be ejected from the orifice. The method includes positioning the head with the orifice facing the substrate. Multiple droplets of the biopolymer or biomonomer fluid are dispensed from the head orifice so as to form an array of droplets on the substrate. A gas flow is directed through a venturi which has a throat opening communicating with the dispensing head chamber. A venturi control valve which particularly communicate with an outlet of the venturi, is adjusted to alter the chamber pressure. The venturi may be driven by a source of inert anhydrous compressed gas which assists in maintaining fluid in the head isolated from moisture.

SMART Layer and SMART Suitcase for structural health monitoring applications

Abstract: Knowledge of integrity of in-service structures can greatly enhance their safety and reliability and lower structural maintenance cost. Current practices limit the extent of real-time knowledge that can be obtained from structures during inspection, are labor-intensive and thereby increase life-cycle costs. Utilization of distributed sensors integrated with the structure is a viable and cost-effective means of monitoring the structure and reducing inspection costs. Acellent Technologies is developing a novel system for actively and passively interrogating the health of a structure through an integrated network of sensors and actuators. Acellent's system comprises of SMART Layers, SMART Suitcase and diagnostic software. The patented SMART Layer is a thin dielectric film with an embedded network of distributed piezoelectric actuators/sensors that can be surface-mounted on metallic structures or embedded inside composite structures. The SMART Suitcase is a portable diagnostic unit designed with multiple sensor/actuator channels to interface with the SMART Layer, generate diagnostic signals from actuators and record measurements from the embedded sensors. With appropriate diagnostic software, Acellent's system can be used for monitoring structural condition and for detecting damage while the structures are in service. This paper enumerates on the SMART Layer and SMART Suitcase and their applicability to composite and metal structures.

Method and apparatus for linear characterization of multiterminal single-ended or balanced devices

Abstract: One embodiment of the invention comprises a multiport test set 'MTS' that characterizes a multiterminal DUT (128). The multiport test set comprises a plurality of ports 'N-ports', a signal generator (100) that provides a test signal over a frequency range, a reference receiver (102) coupled (101) to the signal generator that measures the test signal to determine a reference value, and at least one test channel receiver that measures the test signal at each port of the multiport test set. the multiport test set further comprises a switching device (103), coupled between the signal generator, the plurality of ports of the multiport test set and the at least one test channel receiver, that couples the test signal to any port of the multiport test set and to the at least one test channel receiver. The multiport test set further comprises a device for determining S-parameters [S] of the DUT from the test signal measurements at each port of the multiport test set and the reference value, and for converting the S-parameters to a time domain representation.

Optical sensor for sensing multiple analytes

Abstract: A device for analyzing simultaneously multiple analytes in a fluid of unknown composition. The device includes a plurality of sensors, a light source for providing light to shine on the sensors, light detectors, and a processor. The sensors are exposed to a sample of the fluid of unknown composition. The plurality of sensors includes groups of sensors, each group targeting a specific analyte and including one or more sensors that contain an analyte-specific chemical that interacts more specifically with one analyte than with some other analytes to be analyzed. Each sensor in each group has a different chemical interacting with the analyte to target it. The light source shines light on the sensors of the plurality of sensors to cause light interaction with the sensors. The differences in the sensors lead to differences in the light interaction. The light detectors detects the light interaction by the sensors. The processor analyzes the light interaction by the sensors to take into account interference in light interaction among the analytes, thereby determining the concentration of each of the analytes in the fluid.

Methods and apparatus for providing data for enabling location of a mobile communications device

Abstract: A system for determining location of a mobile communications device obtains data for that purpose by monitoring signalling links in a communications network supporting the device. Data from signalling messages concerning propagation of signals between the device and the network are enhanced by the addition of data from other kinds of messages to facilitate use of the propagation data in determining the device's location.

Method of providing differential frequency adjusts in a thin film bulk acoustic resonator (FBAR) filter and apparatus embodying the method

Abstract: A method for fabricating a resonator, and in particular, a thin film bulk acoustic resonator (FBAR), and a resonator embodying the method are disclosed. An FBAR is fabricated on a substrate by mass loading piezoelectric (PZ) layer between two electrodes. For a substrate having multiple resonators, only selected resonator is mass loaded to provide resonators having different resonance frequencies on the same substrate.

Network monitoring system with built-in monitoring data gathering

Abstract: The network monitoring system comprises a network router with built-in monitoring data gathering. The network router includes channels through which data pass in packets. Each of the packets includes a packet header. The network router additionally includes a header copier and a packet generator. The header copier generates a header copy from the packet header of at least some of the packets. The packet generator receives the header copies and forms monitoring data packets from them. Each monitoring data packet additionally represents temporal data relating to the header copies included in it. A method of obtaining performance data relating to a data transmission network that includes a node passes data through the node in packets. Each of the packets includes a packet header. At least some of the packet headers are copied to obtain respective header copies as monitoring data from which monitoring data packets are formed. The monitoring data packets additionally represent temporal data relating to the header copies included in them. The monitoring data packets are transmitted and the performance data are generated from the monitoring data contained in the monitoring data packets.

Signal analysis using a multiresolution form of the singular value decomposition

Abstract: This paper proposes a multiresolution form of the singular value decomposition (SVD) and shows how it may be used for signal analysis and approximation. It is well-known that the SVD has optimal decorrelation and subrank approximation properties. The multiresolution form of SVD proposed here retains those properties, and moreover, has linear computational complexity. By using the multiresolution SVD, the following important characteristics of a signal may he measured, at each of several levels of resolution: isotropy, sphericity of principal components, self-similarity under scaling, and resolution of mean-squared error into meaningful components. Theoretical calculations are provided for simple statistical models to show what might be expected. Results are provided with real images to show the usefulness of the SVD decomposition.

Bulk acoustic resonator perimeter reflection system

Abstract: A bulk acoustic resonator having a high quality factor is formed on a substrate having a depression formed in a top surface of the substrate. The resonator includes a first electrode, a piezoelectric material and a second electrode. The first electrode is disposed on the top surface of the substrate and extends beyond the edges of the depression by a first distance to define a first region therebetween. The piezoelectric material is disposed on the top surface of the substrate and over the first electrode, and the second electrode is disposed on the piezoelectric material. The second electrode includes a portion that is located above the depression. The portion of the second electrode that is located over the depression has at least one edge that is offset from a corresponding edge of the depression by a second distance to define a second region therebetween. The first and second regions have different impedances, as a result of the different materials located in the two regions. In addition, the first and second distances are approximately equal to a quarter-wavelength of a sound wave travelling laterally across the respective region, such that reflections off of the edges of the regions constructively interfere to maximize the reflectivity of the resonator.

Exploiting CMOS reverse interconnect scaling in multigigahertz amplifier and oscillator design

Abstract: The increasing number of interconnect layers that are needed in a CMOS process to meet the routing and power requirements of large digital circuits also yield significant advantages for analog applications. The reverse thickness scaling of the top metal layer can be exploited in the design of low-loss transmission lines. Coplanar transmission lines in the top metal layers take advantage of a low metal resistance and a large separation from the heavily doped silicon substrate. They are therefore fully compatible with current and future CMOS process technologies. To investigate the feasibility of extending CMOS designs beyond 10 GHz, a wide range of coplanar transmission lines are characterized. The effect of the substrate resistivity on coplanar wave propagation is explained. After achieving a record loss of 0.3 dB/mm at 50 GHz, coplanar lines are used in the design of distributed amplifiers and oscillators. They are the first to achieve higher than 10 GHz operating frequencies in a conventional CMOS technology.

Home security video system using internet technique

Abstract: A security system including several camera devices and a communication device in sites at which monitoring is required by a user. The several camera devices may constantly monitor the sites. The camera devices have motion detecting functions and provide unusual status reporting signals and necessary image information to the communications device when the movements of an intruder have been detected. The communication device communicates with and is connected to a server that serves as an information center via the internet line when unusual status signals have been received. The information from the camera devices is also sent to server. The server automatically notifies the user by a predetermined user-selected method. The notified user can access the server and confirm the information.

One chip USB optical mouse sensor solution

Abstract: An apparatus for controlling the position of a screen pointer for an electronic device having a display screen includes a light source for illuminating an imaging surface, thereby generating reflected images. The apparatus includes a single chip for receiving the reflected images, generating digital representations of the reflected images, and generating a first set of movement data based on the digital representations of the reflected images. The first set of movement data is indicative of relative motion between the chip and the imaging surface. The single chip includes a serial interface for outputting motion data in a serial format based on the movement data.

Systems and methods of monitoring thin film deposition

Abstract: Systems and methods of monitoring thin film deposition are described. In one aspect, a thin film deposition sensor includes an acoustical resonator (e.g., a thin film bulk acoustical resonator) that has an exposed surface and is responsive to thin film material deposits on the exposed surface. A substrate clip may be configured to attach the thin film deposition sensor to a substrate. A transceiver circuit may be configured to enable the thin film deposition sensor to be interrogated wirelessly. A method of monitoring a thin film deposition on a substrate also is described.

Thin film bulk acoustic resonator (FBAR) and inductor on a monolithic substrate and method of fabricating the same

Abstract: An apparatus having both a resonator and an inductor fabricated on a single substrate and a method of fabricating the apparatus are disclosed. The apparatus includes a resonator and an inductor that is connected to the resonator. Both the resonator and the inductor are fabricated over their respective cavities to produce a high Q-factor filter circuit.

Optical screen pointing device with inertial properties

Abstract: An apparatus for controlling the position of a screen pointer for an electronic device having a display screen includes an imaging surface against which a portion of the tip of a human digit may be placed. A light source illuminates that portion of the tip of the digit that is placed against the imaging surface, thereby generating reflected images. The apparatus includes a motion transducer. A lens receives the reflected images and directs the reflected images onto the motion transducer. The motion transducer generates digital representations of the reflected images. The motion transducer generates a first set of movement data based on the digital representations of the reflected images. The first set of movement data is indicative of motion of the tip of the digit across the imaging surface. A controller generates a second set of movement data when the tip of the human digit is removed from the imaging surface. The second set of movement data is indicative of motion of the tip of the digit across the imaging surface prior to removal of the tip.