Texas Instruments Corporation

Other

James Thomas Carlo

David C Bullock

Shalendra K Singh

Alvis D Stephenson, Jr

Robert E Fontana, Jr

John Matthew Cioffi

William E Nelson

Larry J Hornbeck

Peter P Chow

Hon W Lam

Carlos Aldana

Atul Salvekar

Louise Min Chuin Hoo

Methods and devices for adaptively changing a parameter (such as sub-carrier bit allocation and/or gain) in a multi-carrier communication signal are described. In a method aspect, a unit that determines a need for a change sends an express change request to a second unit. The change request identifies one or more specific sub-carrier carrier to be altered and a desired value for the parameter to be changed for each identified sub-carrier. The requesting unit then monitors the communication signal it receives to determine whether the requested change has been implemented. The determination of whether the requested change has been implemented is based at least in part upon an analysis of a portion of the received communication signal that was intended to be changed. In another aspect of the invention, the change request command includes a header, a control field, at least one sub-carrier identifier, at least one desired parameter value indicator, and an error field. The header identifies the command as a change request command. The control field includes a tone count that indicates the number of tones to be altered. Each sub-carrier identifier identifies a specific sub-carrier to be altered and each desired parameter value indicator identifies a desired parameter value for its associated sub-carrier. The error field permits the unit receiving the change request to detect whether there is an error in its interpretation of the change request command.

Express bit swapping in a multicarrier transmission system

An image projection system for producing a projected image in response to electrical signals which represent the image to be projected. The projection system includes input capability to produce electrical signals in response to an image to be projected. These electrical signals are then transmitted to a light modulator which receives light from an external source. The light modulator consists of arrays of deformable mirrors which selectively deflect the light from the external source in response to the electrical signals received from the input capability. The deflected light is absorbed by opaque stops. The undeflected light travels through optics which form the projected image. A printer using this image projection system is also disclosed. The printer further includes the ability to develop the projected image in such a manner that the image is transferrable to a paper surface in a printer in such a manner that the image is reproduced upon the surface in a printer form.

Deformable mirror electrostatic printer

A magnetic bubble domain package in which a magnetic bubble domain chip is bonded to conductors disposed on a thin film interconnect member which is formed to allow a reduction in the volume of the drive coils of the package. The conductors of the interconnect member are bonded to a lead frame which provides signal leads for the magnetic bubble domain chip and the drive coils. The interconnect member with magnetic bubble domain chip and lead frame bonded thereto is encapsulated with a molding compound, the chip being located precisely within the mold in order to insure placement of the chip in the geometric center of the drive coils. The drive coils are prewound and slipped onto the premolded package through slots formed during the molding process to reduce the volume of the coils, and the coils terminated directly onto the signal leads of the lead frame. This chip substructure is supplied with the magnetic field prependicular to the planar surface of the chip by means of a bias field structure formed by permanent magnets secured within an open ended tubular housing which acts as a shield to shunt stray magnetic fields in the external operating environment of the device. A second molding operation encapsulates the chip substructure within the bias field structure to complete the package.

Single chip molded magnetic bubble memory package

Magnetic bubble domain memory circuit in which magnetizable overlay patterns of magnetically soft material, e.g. permalloy, are provided as bubble propagation elements on a bubble-supporting magnetic layer to define major and minor bubble propagation paths. The major bubble propagation paths provide interchangeable bubble input and output sections, and the minor bubble propagation paths are in the form of closed storage loops providing a bubble storage section comprising first and second pairs of blocks. Bubble generators are provided for each of the blocks included in the first and second pairs thereof comprising the bubble storage section, along with first and second detectors and input/output tracks of bubble propagation elements associated with the respective pairs of blocks of storage loops. Swap transfer/replicate gates are disposed between the input/output tracks and each of the storage loops included in the blocks of storage loops. These gates are alternately operable in a swap transfer mode and a replicate mode so as to simultaneously transfer data as represented by magnetic bubbles and voids from the tracks to the storage loops and from the storage loops to the tracks when operated in a swap transfer mode, and to split respective magnetic bubbles incident thereon in a replicate mode to form a duplicate magnetic bubble in addition to the original magnetic bubble so as to preserve the data intact in the minor storage loop while delivering a bubble to a detector for readout. The first and second bubble detectors are 180.degree. out of phase with respect to each other and are operable during respective halfcycles of a bubble propagation cycle to sense the presence or absence of magnetic bubbles. Thus, respective data bits from different blocks are alternately sensed by the first and second bubble detectors in each bubble propagation cycle to provide a data readout rate twice the field rate.

Block replicate magnetic bubble memory circuit for high speed data

Magnetic bubble domain memory circuit in which magnetizable overlay patterns of magnetically soft material, e.g. permalloy, are provided as bubble propagation elements on a bubble-supporting magnetic layer to define major and minor bubble propagation paths. The bubble propagation elements are arranged to form major propagation paths defining a bubble input section and a bubble output section respectively. A plurality of minor propagation paths in the form of closed storage loops defining a bubble storage section are disposed between the input and output bubble sections, being arranged in even and odd blocks of minor propagation paths. Input swap transfer gates and output replicate gates are provided between the bubble storage loops and the input and output sections respectively. The input swap transfer gates and the output replicate gates are of double level construction, each type of gate including a hairpin element at the first level and a 90.degree. hook-like element at the second level which is correlated into bubble propagation elements included in a minor storage loop. The 90.degree. hook-like elements of corresponding swap transfer and replicate gates are respectively situated at the input and output ends of the minor storage loops, forming the opposite bights of the loop. Bubble generators and detectors are associated with the input and output bubble sections respectively at the opposite ends of the minor storage loops to provide a magnetic bubble domain memory chip for data processing purposes. Data as represented by the presence or absence of a magnetic bubble is transferred into the minor storage loops and replicated outwardly therefrom into the bubble output section for detection in a manner enabling such data to be received by the bubble detector for readout at the field rate.

Magnetic bubble memory circuit with input swap and output replicate gates

A magnetic bubble domain package suitable for single or multiple chips in which the coil assembly for producing the rotating magnetic field necessary for bubble movement and logical operations to be performed on these chips comprises a pair of coils wound on a magnetic body in orthogonal relationship with respect to each other which is located external to said chip or chips in order to reduce coil size and power requirements. The package employs an open bias field magnet assembly which comprises an open-ended tubular housing constructed of shielding material and having permanent magnets mounted therein with soft magnetic plates disposed on the permanent magnets. An alternate embodiment employs only a single permanent magnet and a single soft magnetic plate secured within the tubular housing, and uses the magnetic body of the coil assembly as part of the bias field assembly. The chip substructure which is served by this bias field assembly employs a metal plate as an image current producer to increase the uniformity of the drive field. An interconnect member constructed of a thin film of insulating material with electrical conductors disposed thereon is used to provide the interface between the external signal leads of the package and the magnetic bubble domain chip.

External drive coil magnetic bubble package

A magnetic bubble detector comprising a planar layer of magnetic material in which magnetic bubble domains can be moved and a thin planar film on one surface of that layer. The layer has a magnetization perpendicular to the plane of the layer while the film has a magnetization in the plane thereof. The planar layer and film comprise an optical waveguide for propagation of linearly polarized light therethrough along a first axis. Linearly polarized light is coupled into the guide. A bubble expander stretches bubble domains in a direction transverse to their direction of movement as they are moved in the layer of magnetic material past the light guide on a second axis transverse the first axis. A sensor including a light coupling device for coupling light out of said waveguide senses changes in the polarization mode of the light propagating along the axis of the waveguide whereby the fringing field of the stretched bubble will modulate the polarized light propagating along the first axis and provide a light output signal from the sensor thereby indicating the passage of a magnetic domain.

Magnetic bubble detector

A parallel access magnetic bubble memory system comprising a planar thin film optical waveguide for the propagation of linearly polarized light along a first axis and a coupler for coupling light into the guide. Detectors are positioned along the axis of the waveguide. Magnetic bubbles are moved from memory storage locations past respective detectors on respective second axes each transverse the first axis. Each of the detectors includes a coupler for coupling light out of the waveguide. The passage of magnetic bubbles past each respective detector will modulate the polarized light by the fringing fields of the bubbles and provide discrete light output signals from the respective detectors thereby indicating the passage of these bubbles.

Growing community of inventors

Richardson, TX, United States of America

James Thomas Carlo