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Krishnamurthy, US
Arvind Krishnamurthy, Seattle, WA US
| Patent application number | Description | Published |
|---|---|---|
| 20090323972 | PRIVACY-PRESERVING LOCATION TRACKING FOR DEVICES - A privacy-preserving device-tracking system and method to assist in the recovery of lost or stolen Internet-connected mobile devices. The function of such a system seem contradictory, since it is desirable to hide a device's legitimately-visited locations from third-party services and other parties to achieve location privacy, while still enabling recovery of the device's location(s) after it goes missing by tracking the device to determine its location. An exemplary embodiment uses a DHT for storing encrypted location information and other forensic information in connection with indices that are successively determined based on initial pseudorandom seed information (i.e., state) that is retained by the owner of the device. Using the seed information, the software can determine indices mapped to location information stored after the device went missing, enabling the device to be located. Numerous extensions are discussed for the basic exemplary design that increase its suitability for particular deployment environments. | 12-31-2009 |
Dhileepkumar Krishnamurthy, Danbury, CT US
| Patent application number | Description | Published |
|---|---|---|
| 20080214870 | Method of Preparing Amine Stereoisomers - This invention provides intermediates useful in a method of preparing amine stereoisomers. It also provides a method of preparing sulfoxide and sulfinylamine stereoisomers using certain of the intermediates. | 09-04-2008 |
Dhileepkumar Krishnamurthy, Brookfield, CT US
| Patent application number | Description | Published |
|---|---|---|
| 20090088571 | Synthesis of 6,7-Dihydro-5H-imidazo[1,2-a]imidazole-3-sulfonic acid amides - Disclosed is a multi-step process for preparing a compound of Formula I: | 04-02-2009 |
| 20090137815 | Process for Making Cytokine Inhibiting Compounds Containing 4- and 5-Imidazolyl Rings and the Intermediates Thereof - Disclosed are processes for making compounds containing 4- and 5-imidazolyl rings, also disclosed are the inter-mediates useful in the processes disclosed herein. | 05-28-2009 |
| 20100222585 | PREPARATION OF DIHYDROTHIENO [3, 2-D] PYRIMIDINES AND INTERMEDIATES USED THEREIN - The invention relates to improved methods of preparing dihydrothienopyrimidines of formula 1, and intermediates thereof, (I) wherein X is SO or SO | 09-02-2010 |
| 20100240879 | PROCESSES FOR PREPARING OF GLUCOPYRANOSYL-SUBSTITUTED BENZYL-BENZENE DERIVATES AND INTERMEDIATES THEREIN - The present invention relates to processes for preparing the compounds of general formula I, | 09-23-2010 |
| 20100317848 | PROCESS FOR THE SYNTHESIS OF DERIVATIVES OF 3-AMINO-TETRAHYDROFURAN-3-CARBOXYLIC ACID AND USE THEREOF AS MEDICAMENTS - The present invention relates to a process for the manufacturing of substituted 3-amino-tetrahydrofuran-3-carboxylic acid amides of general formula (I) and their precursors in high optical purity to the precursors of the synthesis of substituted S-Amino-tetrahydrofuran-S-carboxylic acid amides of general formula (I) in high optical purity, and to the tautomers, enantiomers, diastereomers, mixtures and salts of substituted 3-amino-tetrahydrofuran-3-carboxylic acid amides of general formula (I) in high optical purity, particularly the physiologically acceptable salts thereof with inorganic or organic acids or bases, which have valuable properties. | 12-16-2010 |
| 20110130563 | SYNTHESIS IF DIHYDROTHIENO[3,2-D]PYRIMIDINE DIOLS - The present invention relates to an improved process for the preparation of dihydrothieno[3,2-d]pyrimidine diols, and similar pyrimidine diols, that is efficient, high-yielding, and does not require expensive and potentially unstable intermediates. The diols are used as intermediates in the synthesis of pyrimidine compounds which inhibit PDE4, and are thus useful in the treatment of respiratory or gastrointestinal diseases and complaints, peripheral or central nervous system diseases and disorders, inflammatory conditions, and cancers. | 06-02-2011 |
| 20110294828 | PROCESS FOR PREPARING A POLYMORPH OF THE CHOLINE SALT OF A PYRIMIDIN-5-YL ACETIC ACID DERIVATIVE - Provided is a process for preparing a choline salt of [4,6-bis(dimethylamino)-2-(4-{[4-(trifluoromethyl)benzoyl]amino}benzyl)pyrimidin-5-yl]acetic acid. The process of the invention is useful for preparing the salt in purer forms of the salt. Also disclosed is a more pure form of the of choline salt of [4,6-bis(dimethylamino)-2-(4-{[4-(trifluoromethyl)benzoyl]amino}benzyl)pyrimidin-5-yl]acetic acid. | 12-01-2011 |
Gautham Krishnamurthy, Raleigh, NC US
| Patent application number | Description | Published |
|---|---|---|
| 20100007512 | Tongue Operated Magnetic Sensor Based Wireless Assistive Technology - An assistive apparatus and method for remote control of an appliance by a subject are provided. The apparatus can comprise a tracer unit affixed to the tongue of the subject such that a change in position of the tongue changes position of the tracer; at least one sensor for detecting a position of the tracer unit; and a transmitter for transmitting a sensor signal to an appliance based on the detected position of the tracer unit, wherein the sensor signal effects control of the appliance. A method for tracking movement, position, or both of a tongue in a subject using the assistive apparatus is also provided. | 01-14-2010 |
Gowri Krishnamurthy, Allentown, PA US
| Patent application number | Description | Published |
|---|---|---|
| 20120128560 | Process and System for Syngas Treatment - A process for the clean-up of a crude syngas stream having widely varying composition and particulate load. The process includes quenching the crude syngas stream with a liquid stream to cool the syngas stream and remove particulates, tars and heavier hydrocarbon compounds. The process further includes co-scrubbing the syngas stream to remove both HCl and NH | 05-24-2012 |
Harish Krishnamurthy, Cambridge, MA US
| Patent application number | Description | Published |
|---|---|---|
| 20110231164 | GENERATING FACIES PROBABLITY CUBES - A method for generating one or more geological models for oil field exploration. The method includes receiving one or more well facies logs, a vertical facies proportion curve, a lateral proportion map, a variogram model and a global target histogram. The method then includes generating a facies probability cube using a modified Sequential Gaussian Simulation (SGSIM) algorithm, the well facies logs, the vertical facies proportion curve, the lateral proportion map and the variogram model. After generating the facies probability cube, the method includes matching the facies probability cube to the global histogram and generating the geological models based on the matched facies probability cube. | 09-22-2011 |
Jagadeesh Krishnamurthy, Troy, MI US
| Patent application number | Description | Published |
|---|---|---|
| 20100071611 | MOVING GRADUATION LIGHTING ACCENT FROM POINTER - A gauge may employ a dial plate, a pointer shaft driven by a motor, a printed circuit board having a plurality of light sources, such as LEDs, and a motor. An upper pointer may be located on a viewed side of the dial plate and a lower pointer may be located on an unviewed side of the dial plate. The upper and lower pointers are attached to the pointer shaft. The lower pointer is positioned to receive light from the light source and direct the light into indicia and graduations of the dial plate, and into the upper pointer. An area surrounding the upper pointer is more brightly lit than other areas of the dial plate. A light-collecting ring may collect light and transmit light into the lower pointer. The ring may be an integral or attached part of the lower pointer or it may be a detached and separate piece. | 03-25-2010 |
Jay Krishnamurthy, Framingham, MA US
| Patent application number | Description | Published |
|---|---|---|
| 20090070403 | DISTRIBUTED ENVIRONMENT CONTROLLED ACCESS FACILITY - A computer implemented web based access control facility for a distributed environment, which allows users to request for access, take the request through appropriate approval work flow and finally make it available to the users and applications. This program also performs an automatic task of verifying the health of data, access control data as well as the entitlements, to avoid malicious user access. The system also provides an active interface to setup a backup, to delegate the duty in absence. Thus this system provides a comprehensive facility to grant, re-certify and control the entitlements and users in a distributed environment. | 03-12-2009 |
Lakshmi Krishnamurthy, Wilmington, DE US
| Patent application number | Description | Published |
|---|---|---|
| 20110139331 | METHOD FOR INCREASING THE STRENGTH AND SOLVENT RESISTANCE OF POLYIMIDE NANOWEBS - The invention provides a method for enhancing the properties of polyimide nanowebs, the method comprising subjecting a nanoweb consisting essentially of a plurality of nanofibers of an aromatic polyimide to a temperature at least 50 C.° higher than the imidization temperature thereof for a period of time in the range of 5 seconds to 20 minutes, thereby preparing an enhanced nanoweb. Also provided is a multi-layer article comprising the enhanced nanoweb, and an electrochemical cell comprising the multi-layer article. | 06-16-2011 |
| 20110143207 | MULTI-LAYER ARTICLE COMPRISING POLYIMIDE NANOWEB - This invention provides a multi-layer article comprising a first electrode material, a second electrode material, and a porous separator disposed between and in contact with the first and the second electrode materials, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a method for preparing the multi-layer article, and an electrochemical cell employing the same. A multi-layer article comprising a polyimide nanoweb with enhanced properties is also provided. | 06-16-2011 |
| 20110143217 | ELECTROCHEMICAL CELL COMPRISING A SEPARATOR COMPRISING A NANOWEB CONSISTING ESSENTIALLY OF NANOFIBERS OF FULLY AROMATIC POLYIMIDE - This invention provides an electrochemical cell comprising a housing having disposed therewithin, an electrolyte, and a multi-layer article at least partially immersed in the electrolyte; the multi-layer article comprising a first metallic current collector, a first electrode material in electrically conductive contact with the first metallic current collector, a second electrode material in ionically conductive contact with the first electrode material, a porous separator disposed between and contacting the first electrode material and the second electrode material; and, a second metallic current collector in electrically conductive contact with the second electrode material, wherein the porous separator comprises a nanoweb consisting essentially of a plurality of nanofibers of a fully aromatic polyimide. Also provided is a process for preparing the multi-layer article. Further provided is an electrochemical cell wherein the separator is a polyimide nanoweb with enhanced properties. | 06-16-2011 |
| 20110144297 | RAPID THERMAL CONVERSION OF A POLYAMIC ACID FIBER TO A POLYIMIDE FIBER - The invention provides a process comprising heating a polyamic acid fiber to a temperature in the range of a first temperature and a second temperature for a period of time in the range of 5 seconds to 5 minutes to form a polyimide fiber, wherein the first temperature is the imidization temperature of the polyamic acid and the second temperature is the decomposition temperature of the polyimide | 06-16-2011 |
Lokesha B. Krishnamurthy, Sanford, FL US
| Patent application number | Description | Published |
|---|---|---|
| 20120066446 | PHYSICAL TO VIRTUAL DISKS CREATION (P2V) METHOD, BY HARVESTING DATA FROM CRITICAL SECTORS - A virtual disk can be created by using data from critical sectors of a primary physical disk. The creation of a virtual disk involves receiving sector numbers and corresponding data for critical sectors of a primary physical disk on a primary computing system, creating a virtual disk that comprises sectors, and writing data from the critical sectors of the primary physical disk into respective sectors of the virtual disk. | 03-15-2012 |
Praveen Krishnamurthy, St. Louis, MO US
| Patent application number | Description | Published |
|---|---|---|
| 20100098081 | LONGEST PREFIX MATCHING FOR NETWORK ADDRESS LOOKUPS USING BLOOM FILTERS - Methods and systems for performing parallel membership queries to Bloom filters for Longest Prefix Matching, where address prefix memberships are determined in sets of prefixes sorted by prefix length. Hash tables corresponding to each prefix length are probed from the longest to the shortest match in the vector, terminating when a match is found or all of the lengths are searched. The performance, as determined by the number of dependent memory accesses per lookup, is held constant for longer address lengths or additional unique address prefix lengths in the forwarding table given that memory resources scale linearly with the number of prefixes in the forwarding table. For less than 2 Mb of embedded RAM and a commodity SRAM, the present technique achieves average performance of one hash probe per lookup and a worst case of two hash probes and one array access per lookup. | 04-22-2010 |
| 20110231446 | Method and Apparatus for Performing Similarity Searching - A system and method for performing similarity searching is disclosed. This includes a programmable logic device configured to include a pipeline that comprises a matching stage, the matching stage being configured to receive a data stream comprising a plurality of possible matches between a plurality of data strings and a plurality of substrings of a query string. The pipeline may further include an ungapped extension prefilter stage located downstream from the matching stage, the prefilter stage being configured to shift through pattern matches between the data strings and the plurality of substrings of a query string and provide a score so that only pattern matches that exceed a user defined score will pass downstream from the prefilter stage. The matching stage may include at least one Bloom filter. | 09-22-2011 |
Ram Krishnamurthy, Westford, MA US
| Patent application number | Description | Published |
|---|---|---|
| 20100070894 | FEDERATED CALENDAR ENTRY PRESENCE INDICATOR - A method for indicating the presence of federated calendar entries in a currently viewed time period of a calendar and/or scheduling application, includes: receiving a user's selection for a date range in a calendar and/or scheduling application; determining whether there are one or more federated calendars associated with the user's calendar and/or scheduling application; wherein in the event there are one or more federated calendars associated with the user's calendar and/or scheduling application: determining whether there are one or more events from the one or more federated calendars in the selected date range; and wherein in the event there are federated calendar events in the selected date range: generating a calendar and/or scheduling page with one or more indicators for federated calendars with events in the selected date range. | 03-18-2010 |
| 20110113375 | SYSTEM AND METHOD FOR ILLUSTRATING A MENU OF INSIGHTS ASSOCIATED WITH VISUALIZATIONS - A system and method are provided for generating one or more menus having options that display insights from visualizations. The options presented in the menus enable users to determine relationships between elements of the visualization. The relationships may be displayed textually to enable user to navigate the menus using a keyboard, a text-to-voice converter, and/or pointers. | 05-12-2011 |
| 20110317523 | MERGING CALENDAR ENTRIES - A method, operable on a processing device, for merging calendar entries may include receiving a plurality of calendar entries each associated with entry identification data. The method may also include comparing by the processing device at least a portion of the entry identification data associated with each of the calendar entries. The method may additionally include merging, by the processing device, the calendar entries based at least in part on comparing of at least the portion of the entry identification data associated with each of the at least two calendar entries. The method may further include comparing at least one time attribute associated with each of the calendar entries and comparing at least one textual attribute associated with each of the calendar entries and basing merging the calendar entries additionally on comparing the time attributes and the textual attributes. | 12-29-2011 |
Ravishankar Krishnamurthy US
| Patent application number | Description | Published |
|---|---|---|
| 20110289558 | NETWORK APPLICATION LAYER ROUTING - Techniques for network application layer routing are provided. Requests for services are inspected at an application layer of a network. A priority for a requestor is obtained and in response to the priority the requests are routed to particular processing environments. Depending on the priority the processing environments may be high performing or low performing. | 11-24-2011 |
Sadashivan Krishnamurthy, Redmond, WA US
| Patent application number | Description | Published |
|---|---|---|
| 20110219169 | Buffer Pool Extension for Database Server - Aspects of the subject matter described herein relate to a buffer pool for a database system. In aspects, secondary memory such as solid state storage is used to extend the buffer pool of a database system. Thresholds such as hot, warm, and cold for classifying pages based on access history of the pages may be determined via a sampling algorithm. When a database system needs to free space in a buffer pool in main memory, a page may be evicted to the buffer pool in secondary memory or other storage based on how the page is classified and conditions of the secondary memory or other storage. | 09-08-2011 |
| 20120072652 | MULTI-LEVEL BUFFER POOL EXTENSIONS - A buffer manager that manages blocks of memory amongst multiple levels of buffer pools. For instance, there may be a first level buffer pool for blocks in first level memory, and a second level buffer pool for blocks in second level memory. The first level buffer pool evicts blocks to the second level buffer pool if the blocks are not used above a first threshold level. The second level buffer pool evicts blocks to a yet lower level if they have not used above a second threshold level. The first level memory may be dynamic random access memory, whereas the second level memory may be storage class memory, such as a solid state disk. By using such a storage class memory, the working block set of the buffer manager may be increased without resorting to lower efficiency random block access from yet lower level memory such as disk. | 03-22-2012 |
Shashank Krishnamurthy, Madison, WI US
| Patent application number | Description | Published |
|---|---|---|
| 20090273192 | Doubly fed axial flux induction generator - A doubly fed axial flux induction generator may include a prime mover configured to provide mechanical energy. The doubly fed axial flux induction generator may also include a rotor assembly coupled to the prime mover, wherein the prime mover is configured to rotate the rotor assembly. The doubly fed axial flux induction generator may further include a stator. The doubly fed axial flux induction generator may further include a power electronics module coupled to the rotor assembly and the stator, wherein the power electronics module is arranged in parallel with the prime mover, and is configured to assist with converting the mechanical energy into electrical energy, as well as with dispatching power between the prime mover and an energy storage device. The energy storage device may be coupled to the power electronics module, and may be configured to meet variations in power demand. | 11-05-2009 |
Shrinidhi Krishnamurthy, Redmond, WA US
| Patent application number | Description | Published |
|---|---|---|
| 20110320366 | Computer-Implemented System And Method For Transparently Interfacing With Legacy Line Of Business Applications - A computer-implemented system and method for transparently interfacing with legacy line of business applications is provided. A plurality of legacy line of business applications execute on a line of business server platform. A connector is interfaced to each legacy line of business application. Each legacy line of business application implements business logic for a specific business need. A dashboard application executes on a client platform into which at least one Widget application is tailored to and installed for one or more of the legacy line of business applications. An enterprise collaboration server executes on a collaboration server platform communicatively interposed between the line of business server platform and the client platform. A data access framework coupled to the dashboard application is provided through a user interface layer. A data service bus coupled to the line of business applications through their respective connector and to the data access framework is provided. | 12-29-2011 |
Subramanian Krishnamurthy US
| Patent application number | Description | Published |
|---|---|---|
| 20110144953 | COMPENSATION OF ELECTROMAGNETIC INTERFERING FIELDS - A system for compensating electromagnetic interfering fields is provided that includes two triaxial magnetic field sensors for outputting real sensor signals; six compensation coils, which are arranged as a cage around an object to be protected, and may individually be actuated; a control unit having six inputs, and six outputs, and a digital processor receiving the sensor signals on the input side, and processing the signals to control signals for the compensation coils. The real sensor signals are converted to virtual sensor signals by a first matrix multiplication for mapping the interfering fields at the location of the object. The virtual sensor signals are made to modified signals by an operator describing the controller structure. The modified signals are converted to real control signals by a second matrix multiplication, which control signals are individually fed to the six compensation coils. | 06-16-2011 |
Udhayakumar Krishnamurthy, Parlin, NJ US
| Patent application number | Description | Published |
|---|---|---|
| 20100151839 | Devices, Systems and Methods for Proactive Call Context, Call Screening and Prioritization - Devices, systems and methods are disclosed which enable a user of a communications device to receive a notification of a priority and a context of a call before answering the call. A caller records a short phrase to be played on the callee's device either in place of ringing or following a predetermined amount of rings controlled by the callee's preferences. Among the callee's preferences is a selection of priority, such as among low, high, and critical. When callee's communications device is in any of these modes, every incoming call is intercepted giving the caller the opportunity to provide a short phrase for the context of the call and choose a priority level. This short phrase is played on the callee's communications device if the specified priority of the call matches or exceeds the current mode set on the callee's communications device, and the callee may answer. If the specified priority of the call falls below the current mode set, then the short phrase and priority are saved, but the call is ignored. Optional device configuration allows a special tone, vibration pattern, or beep to occur on the callee's communications device indicating a call has been ignored. The recorded phrase can then be reviewed on demand. The above solution can also be extended to provide a quick glimpse into the voicemail, either in place of the current tone indicating a voicemail has arrived, or immediately following. | 06-17-2010 |
Umamaheshwar Krishnamurthy, Arlington, TX US
| Patent application number | Description | Published |
|---|---|---|
| 20080315896 | TECHNIQUES AND APPARATUS FOR THE MEASUREMENT OF MUTUAL INDUCTANCE IN A SWITCHED RELUCTANCE MACHINE - A system and technique for measuring the mutual inductance in a switched reluctance machine (SRM). In a first example embodiment of the technique, a voltage pulse is applied to primary coil when the machine is stationery. By measuring current in the primary coil and measuring induced voltages in adjacent open circuited coils mutual inductance may be determined. In another example embodiment, a voltage pulse is applied to the primary coil when the machine is stationery. The secondary coil is allowed to freewheel current through the phase. By measuring time taken by the primary phase to reach a preset value, the mutual inductance for the known position of a rotor can be determined. | 12-25-2008 |
Venkat Krishnamurthy, Acton, MA US
| Patent application number | Description | Published |
|---|---|---|
| 20110080264 | Localizing Tagged Assets in a Configurable Monitoring Device System - In a tag communication system, a method includes determining range information representative of a distance between two tags, and estimating parameter information representative of backscatter signals of a marker tag and an asset tag. A tag is localized according to the range information and the parameter information to provide a localized tag. The range information is determined according to a beacon signal. The system includes a plurality of beacon signals and the method further includes determining the range information according to at least two of the beacon signals. A logical operation is performed on the range information of the two beacon signals. A further beacon signal has a plurality of signal ranges and the range information is determined according to the signal ranges. A logical operation is performed on the range information of the signal ranges. | 04-07-2011 |
| 20110080267 | Calibration of Beamforming Nodes in a Configurable Monitoring Device System - A system for radio frequency identification of a tag in an interrogation zone, includes a calibration node disposed in the interrogation zone to measure a signal strength of radio frequency identification signals from a beamforming system and provide signal data in accordance with the signal strength. A reader node is configured to receive the signal data and adjust the radio frequency identification signals generated by the beamforming system based upon the signal data. At least one of the calibration node, the reader node and the beamforming system is a configurable monitoring system. The calibration node, the reader node, and the beamforming system are coupled in a feedback control loop. The beamforming system includes a plurality of beamforming nodes. A signal of at least one beamforming node is optimized in accordance with the feedback control loop. | 04-07-2011 |
Vijayabhasker Mumudi Krishnamurthy, Lawrenceville, NJ US
| Patent application number | Description | Published |
|---|---|---|
| 20110246344 | Generating Financial Reports - In some embodiments, a method for generating financial reports, includes selecting a first request from a plurality of pending requests. The first request requests a report on information regarding one or more accounts with a financial institution. The first request is separated into a plurality of content requests. The plurality of content requests represent requests for information to be incorporated into the requested report. A plurality of subreports are received in response to each of the plurality of content requests. The requested report is generated in response to the first request by binding each of the plurality of subreports. | 10-06-2011 |
Vijay M. Krishnamurthy, Cambridge, MA US
| Patent application number | Description | Published |
|---|---|---|
| 20090240040 | PURIFICATION OF A BIVALENTLY ACTIVE ANTIBODY USING A NON-CHROMATOGRAPHIC METHOD - The present invention discloses a method of purifying bivalent antibodies or antibody fragments that are active at both Fab sites from a source of antibodies or antibody fragments using a non-chromatographic method that includes inducing the formation of cyclic immunoglobulin aggregates by addition of multivalent hapten to a salt solution of soluble antibodies or antibody fragments, wherein the multivalent hapten possesses a linker between the two haptens effective to prevent the binding of both haptens of the ligand to the same antibody or antibody fragment. | 09-24-2009 |
Vikram Krishnamurthy, Smyrna, GA US
| Patent application number | Description | Published |
|---|---|---|
| 20110128088 | RF SWITCHABLE BALUN - A handheld communication device having an RF front end module has a switchable balun comprising a primary winding having a first two port winding and a second two port winding where a low noise amplifier is operatively coupled to the first and second two port windings and a power amplifier is operatively coupled to the first and second two port windings. A secondary winding is operatively coupled to an antenna, and a transceiver is operatively coupled to the low noise amplifier and the power amplifier. When the switchable balun is in a receive state, the antenna is operatively coupled to the transceiver through the low noise amplifier, and when the switchable balun is in a transmit state, the antenna is operatively coupled to the transceiver through the power amplifier. The ratio of the primary winding to the secondary winding is greater than a one-to-one ratio | 06-02-2011 |
Vikram Bidare Krishnamurthy, Smyrna, GA US
| Patent application number | Description | Published |
|---|---|---|
| 20100033242 | SYSTEM AND METHOD FOR IM3 REDUCTION AND CANCELLATION IN AMPLIFIERS - Sets of power amplifier branches (which comprise an RF/microwave amplifier stage) are power combined within each stage and each set of power amplifier branches are biased in different classes of operation by bias circuits possessing different impedance characteristics such that the fundamental frequency components present at the output are in-phase with one another and the IMD3 components are anti-phase over a broad range of power levels. The RF input signal is provided by the output of the previous stage of the RF/microwave amplifier. The output of each stage is formed by power combining sets of these power amplifier branches, each of which are separately biased, so the fundamental components are additive resulting in the maximum possible output power and the IM3 components cancel partially or completely. IM3 reduction or cancellation can be achieved over a large range of output powers with the use of a feed forward control loop monitoring the input power and appropriately adjusting the bias currents and impedance characteristics of the bias circuits feeding the individual power amplifier branches in each stage of the RF/microwave amplifier. | 02-11-2010 |