Abstract: A multiple access system for a network using multicarrier modulation. To contend for service a subscriber station selects an upcoming frame in whose contention window it will contend, selects a contention slot within the window, selects a contention channel corresponding to a subset of the carriers used by the network, and imposes a contention code differentially on the carriers in the contention channel.
Type:
Grant
Filed:
March 11, 2002
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Manoneet Singh, Jerry Krinock, Thomas Michael Paff
Abstract: Time domain equalizer determination for discrete multitone systems by tone error minimization from a starting point of a single-tone equalizer.
Abstract: Spread spectrum rake receiver estimates number of paths within a chip interval and assigns corresponding fingers. Cross-correlation matrix eigenvalues or direct BER estimates for differing numbers of fingers determine whether one or two fingers assigned to the group of paths within a chip.
Type:
Grant
Filed:
February 23, 2001
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Timothy M. Schmidl, Srinath Hosur, Anand Dabak, Aris Papasakellariou
Abstract: A method of wirelessly communicating is disclosed. The method comprises generating a plurality of tones for a wideband orthogonal frequency division multiplex symbol (310), the tones including a plurality of contiguous zero-valued tones, inverse Fourier transforming the tones to a plurality of time-domain samples (312), copying a plurality of the time-domain samples as a portion of a cyclic block (314), the cyclic block (314) contiguous with the time-domain samples (312), time-domain window filtering the time-domain samples (312) and the cyclic block (314) to form a portion of the wideband orthogonal frequency division multiplex symbol (310), wherein the time-domain window filter (350) is a function ?(k) having the property that ?(k)+?(k+Nfft) is about equal to a constant ? where Nfft is the number of tones, and transmitting the wideband orthogonal frequency division multiplex symbol (310).
Abstract: Hydrogen barriers and fabrication methods are provided for protecting ferroelectric capacitors (CFE) from hydrogen diffusion in semiconductor devices (102), wherein nitrided aluminum oxide (N—AlOx) is formed over a ferroelectric capacitor (CFE), and one or more silicon nitride layers (112, 117) are formed over the nitrided aluminum oxide (N—AlOx). Hydrogen barriers are also provided in which an aluminum oxide (AlOx, N—AlOx) is formed over the ferroelectric capacitors (CFE), with two or more silicon nitride layers (112, 117) formed over the aluminum oxide (AlOx, N—AlOx), wherein the second silicon nitride layer (112) comprises a low silicon-hydrogen SiN material.
Type:
Grant
Filed:
January 11, 2005
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
K. R. Udayakumar, Theodore S. Moise, Scott R. Summerfelt
Abstract: An integrated circuit can have plural core circuits, each having a test access port that is defined in IEEE standard 1149.1. Access to and control of these ports is though a test linking module. The test access ports on an integrated circuit can be arranged in a hierarchy with one test linking module controlling access to plural secondary test linking modules and test access ports. Each secondary test linking module in turn can also control access to tertiary test linking modules and test access ports. The test linking modules can also be used for emulation.
Abstract: An inquiry message is transmitted successively on each of a first plurality of transmit frequencies (44–48) and thereafter successively on each of a second plurality of transmit frequencies (51), in order to ensure that a first wireless communication apparatus that listens on one of the transmit frequencies will receive the inquiry message. The first plurality of transmit frequencies can also be ensured (25–28) to include a frequency on which a second wireless communication apparatus is listening for the inquiry message. With respect to reception of an inquiry message that is transmitted successively on each of first and thereafter second pluralities of transmit frequencies, after receipt (61) of the initial inquiry message and subsequent expiration of a corresponding backoff period (62), the inquiry message is first listened for on a first frequency of the first plurality of transmit frequencies for a predetermined time (63).
Abstract: According to one embodiment of the present invention, a digital micro-mirror device having improved contrast and a method for the same are provided. The digital micro-mirror device includes a plurality of current-carrying conductors on an upper surface of a substrate, each current-carrying conductor having an upper surface; a low-reflectivity metal disposed upon the upper surfaces of the current-carrying conductors; first and second micro-mirrors forming an aperture above the substrate; and wherein the low-reflectivity metal disposed upon on the upper surfaces of the current-carrying conductors reduces reflection of light received through the aperture by the current-carrying conductors.
Abstract: The present invention provides for a method and apparatus for allocating data to subchannels used for ADSL transmission over a communication link which supports further system transmissions. An expected interference impact from the further system transmissions is estimated for the ADSL subchannels. Signal-to-noise ratios (SNRs) for the subchannels are determined for bit loading by an estimator (220). In one embodiment, actual noise associated with the communication link is used at initialization to determine a SNR which is subsequently modified by an adjusting unit (205) prior to bit loading responsive to the estimated interference impact. In another embodiment, a virtual noise signal, indicative of the estimated interference impact and generated by a noise signal generator (235), is summed with the actual noise prior to determining a SNR for bit loading.
Type:
Grant
Filed:
November 14, 2002
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Krista S. Jacobsen, Michael D. Agah, Brian R. Wiese
Abstract: An integrating rod (200) for use with a multiple segment dynamic filter, such as a spiral dichroic color wheel having three or more narrow filters adjacent to the exit face (206) to enable the integrating rod to recapture light rejected by a given segment of the dynamic filter. The rejected light travels back through the integrating rod where a majority of the light strikes the mirrored entrance face (202). Light reflected by the mirrored entrance face, or light exiting through the entrance aperture (204) and returning to the integrating rod after being reflected by the lamp reflector, once again travels to the exit face (206) of the integrating rod (200). After exiting through the exit face (206) of the integrating rod (200) a second time, the recycled light has a good chance of striking a different filter segment of the dynamic filter and being used by the display system.
Abstract: Automatic white balancing and/or autoexposure as useful in a digital camera extracts color channel gains from comparisons of image colors with reference colors under various color temperature illuminants and/or extracts exposure settings from illuminance mean, illuminance variance, illuminance minimum, and illuminance maximum in areas of an image with a trained neural network.
Abstract: An apparatus for driving a write head in response to a data signal includes: (a) a first drive unit coupled with the write head; (b) a second drive unit coupled with the write head; and (c) a control unit coupled with the first and second drive units. The control unit receives the data signal and generates control signals to the first drive and second drive units in response to the data signal. The control signals control the first drive unit to apply a first drive signal to a first write head side in a first signal polarity and control the second drive unit to apply a second drive signal to the a second write head side in a second signal polarity opposite to the first signal polarity when the data signal effects a signal excursion. The first drive signal and the second drive signal are equal in magnitude time coincident.
Abstract: In the proposed method of generating a pulsed output signal from a periodic ramp signal and a reference voltage, the linear range of duty cycles of the pulsed output signal is significantly extended to minimum values. The ramp signal and the reference voltage are applied to inputs of a comparator and the output signal is taken from an output of the comparator. The ramp signal has a ramp that extends between a minimum voltage level and a maximum voltage level. The duty cycle of the pulse signal is controlled by varying the reference voltage between the minimum and maximum voltage levels. The ramp has an initial start section extending from the minimum voltage level and a main section extending between the initial section and the maximum voltage level. The ramp slope has a constant value over the main ramp section and a value greater than the constant value over the initial section.
Abstract: A method of determining CPS data in an OFDM-based, wireless communication system resolves the phase angle difference between training tones in a burst without CPS data and training tones in a burst with CPS data and then demodulates the resulting difference phase angles to determine the CPS data. The method achieves timing correction/compensation in CPS decode operations associated with OFDM-based, wireless communication systems.
Type:
Grant
Filed:
May 14, 2003
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
David P. Magee, Srinath Hosur, Manish Goel
Abstract: Dual gate dielectric layers are formed on a semiconductor substrate for MOS transistor fabrication. A first dielectric layer (30) is formed on a semiconductor substrate (10). A first plasma nitridation process is performed on said first dielectric layer. The first dielectric layer (30) is removed in regions of the substrate and a second dielectric layer (50) is formed in these regions. A second plasma nitridation process is performed on the first dielectric layer and the second dielectric layer. MOS transistors (160, 170) are then fabricated using the dielectric layers (30, 50).
Type:
Grant
Filed:
November 6, 2003
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Rajesh Khamankar, Douglas T. Grider, Hiroaki Niimi, April Gurba, Toan Tran, James J. Chambers
Abstract: Integer transforms of 4×4 blocks of the type used in proposed H.26L but adapted to 16-bit arithmetic by shifts after matrix multiplications and integer approximation matrices absorbing scaling factors.
Abstract: A method and apparatus permit a wireless communication device to be calibrated during manufacturing and subsequently re-calibrated while in use to correct for the effects of temperature changes on transmit power.
Type:
Grant
Filed:
March 11, 2004
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Kirupairaj Asirvatham, John R. Rosenlof
Abstract: A test controller applies test stimulus signals to the input pads of plural die on a wafer in parallel. The test controller also applies encoded test response signals to the output pads of the plural die in parallel. The encoded test response signals are decoded on the die and compared to core test response signals produced from applying the test stimulus signals to core circuits on the die. The comparison produces pass/fail signals that are loaded in to scan cells of an IEEE 1149.1 scan path. The pass/fail signals then may be scanned out of the die to determine the results of the test.
Abstract: A device and a method for controlling resin bleed, the device comprising a substrate having a surface, wherein an interior region, a peripheral region, and an exterior region of the surface are generally defined. An adhesive generally resides on the surface of the substrate in the peripheral region thereof, wherein the adhesive comprises a plurality of components, such as a metal and a resin. A first barrier is formed on the surface of the substrate generally between the adhesive and the exterior region, wherein the first barrier generally prevents one or more of the plurality of components of the adhesive from bleeding onto the exterior region of the surface of the substrate.
Type:
Grant
Filed:
September 23, 2004
Date of Patent:
February 27, 2007
Assignee:
Texas Instruments Incorporated
Inventors:
Robert John Furtaw, John Henry Abbott, Emily Ellen Hoffman
Abstract: A method of increasing the data rate in a wireless Ethernet employs clock switching between the preamble and the encoded data portion of a packet structure. A shift block includes a tail sequence and a head sequence that is inserted between the preamble and the encoded data portion. The clock switching occurs within the shift block between the tail and the head sequences. The tail sequence and the head sequence are each constrained to be a fixed sequence.