Abstract:
A plurality of MEMS devices are formed on a substrate, a sacrificial layer is formed to cover each of the MEMS devices and a protective cap layer is formed on the sacrificial layer. A release hole is formed through the protective cap layer to the underlying sacrificial layer, and a releasing agent is introduced through the release hole to re¬ move the sacrificial layer under the protective cap layer and expose a MEMS device. The release hole is solder sealed, to form a hermet¬ ic seal of the MEMS device. The method for hermetically sealing the release hole comprises forming a wetting surface on a region adja¬ cent the opening and immersing the wetting surface into a viscous solder to draw a portion of the solder to cover and hermetically seal the opening.
Abstract:
Methods and devices for coding of feature locations are disclosed. In one embodiment, a method of coding feature location information of an image includes generating a hexagonal grid, where the hexagonal grid includes a plurality of hexagonal cells, quantizing feature locations of an image using the hexagonal grid, generating a histogram to record occurrences of feature locations in each hexagonal cell, and encoding the histogram in accordance with the occurrences of feature locations in each hexagonal cell. The method of encoding the histogram includes applying context information of neighboring hexagonal cells to encode information of a subsequent hexagonal cell to be encoded in the histogram, where the context information includes context information from first order neighbors and context information from second order neighbors of the subsequent hexagonal cell to be encoded.
Abstract:
Various arrangements for using a k-dimensional tree for a search are presented. A plurality of descriptors may be stored. Each of the plurality of descriptors stored is linked with a first number of stored dimensions. The search may be performed using the k-dimensional tree for one or more query descriptors that at least approximately match one or more of the plurality of descriptors linked with the first number of stored dimensions. The k-dimensional tree may be built using the plurality of descriptors wherein each of the plurality of descriptors is linked with a second number of dimensions when the k-dimensional tree is built. The second number of dimensions may be a greater number of dimensions than the first number of stored dimensions.
Abstract:
In general, techniques are described for performing enhanced sigma-delta modulation. For example, an apparatus comprising a predictive filter unit, an amplifier, an oversampling unit and a sigma-delta modulation unit may implement the techniques. The predictive filter unit performs predictive filtering on an input signal to generate a filtered signal and computes an estimate of a predictive gain as a function of an energy of the input signal and an energy of the filtered signal. The amplifier receives the filtered signal and amplifies the filtered signal based on the predictive gain to generate an amplified signal. The oversampling unit receives the amplifies signal and performs oversampling in accordance with an oversampling rate to generate an oversampled signal. The sigma-delta modulation unit receives the oversampled signal and performs sigma-delta modulation to generate a modulated signal.
Abstract:
A matched filter and peak detector identify peaks of a received signal. The peak detector may detect peaks during a fixed or adjustable time window. The peaks may be used as a preliminary decision (e.g., soft decision) for subsequent receiver decoding operations. The detector may be used to detect high bandwidth signals such as ultra-wide band signal pulses yet consume relatively minimal power.
Abstract:
Aspects include methods and apparatuses for communicating in an ultra-wideband transmission. For example, some aspects include methods and apparatuses for multi-hop communication. For example, some aspects include a method of communicating data. The method includes receiving pulses indicative of a frame during a first time period and transmitting pulses indicative of the frame during a second time period to at least one device. The first and second time periods at least partially overlap. Other aspects include apparatus and devices for multi-hop communication.
Abstract:
This disclosure describes the use of non-dyadic discrete cosine transform (DCT) sizes for performing a DCT. Similarly, this disclosure describes the use of non-dyadic inverse discrete cosine transform (IDCT) sizes for performing an IDCT. Using non-dyadic transform sizes may be less computationally expensive compared to using conventional dyadic transform sizes. Aspects of this disclosure may be useful in any device or system that performs a DCT or IDCT.
Abstract:
A duty cycle scheme for wireless communication employs three or more duty cycle levels. In some aspects, a wireless device may continually scan for signals in an active state associated with a first duty cycle, periodically scan for signals during a periodic state associated with a second duty cycle, and periodically scan for signals during a standby state associated with a third duty cycle. Here, the second duty cycle may be lower than the first duty cycle and the third duty cycle may be lower than the second duty cycle. In some aspects the timing of different states may be correlated. In some aspects each wireless in a system may independently control its duty cycle states.
Abstract:
Apparatus and method for processing signals. A sigma-delta modulator is used. An adaptive dynamic range controller is configured to adaptively adjust the dynamic range of a signal output from the sigma-delta modulator.
Abstract:
A signaling scheme employs transmitted reference pulses having varying phase. The phase of the reference pulses may be varied in a random manner or in accordance with a data stream. In some aspects a transmitter modulates the phase of the reference pulses to encode an additional data stream in a transmitted reference signal. In some aspects these techniques are employed in a heterogeneous network including coherent and non-coherent receivers. In some aspects these techniques may be employed in an ultra-wide band system.