Abstract: A wireless signal processor for use in identifying a maximum Carrier to Noise Interference Ratio (CINR) associated with a plurality of received OFDMA subcarriers has a candidate generator for forming a plurality of candidate values from a particular set of received subcarriers by forming candidate values based on the received subcarriers in combination with possible integer preamble offsets and possible preamble values. A candidate evaluator selects which of the possible preamble values and integer frequency offset values have the maximum CINR, and provides the maximum CINR with IFO and preamble index as outputs.

Abstract: A gain controller for a wireless communication system sets the receiver gain during the initial time duration of a preamble, and for each subsequent symbol computes a new gain value, which is applied at the end of each symbol. An analog to digital converter resolution controller sets the resolution of the ADC to a high resolution during a preamble interval and a first symbol interval, and to a comparatively lower resolution thereafter until the end of the frame. When a new zone is entered, the first symbol of the new zone is sampled at a higher resolution than the subsequent symbols.

Abstract: An apparatus and a process for transferring packet data includes receiving packets from a first interface such as a network interface and transferring data to a second interface such as an SD Bus interface such as SDIO using a protocol such as one described in SDCard.org. The SD Bus second interface operates as a slave device to a master device, and the packet transfer from first interface to second interface includes concatenating length fields and packet data fields from packets received on the first interface to form a superframe which is provided to the second interface at time of data transfer. The formation of each superframe includes starting a timer such that the superframe is transmitted to the second interface by asserting an interrupt on that interface when either the timer expires, the number of packet from the first interface exceeds a threshold, or the amount of data from the first interface exceeds a threshold.

Abstract: An apparatus for deposition of plasma reaction films includes a substrate for the deposition of either thin or thick films. The substrate also allows for a film deposition which adheres to the substrate, and also films which may be removed after deposition. The cathode may be fabricated from individual wires, or it may be fabricated from a single conductor. A macro-particle filter which preferentially traps larger particles may be introduced between a porous cathode and the deposition surface. The macro-particle filter may also carry electrical current as is useful for generating a magnetic field such that a Lorentz force acts preferentially on ionized particles, allowing them to pass through the filter while trapping macroparticles that are not influenced by the magnetic field.

Abstract: A process for equalizing streams of OFDM subcarrier data computes the noise variance for each stream, and forms a stream weighting coefficient by equalizing the noise variance, such that for a first stream having a noise variance ?1 and a second stream having a noise variance of ?2, the first stream is scaled by k 1 = 2 ? ? 2 ? 1 2 + ? 2 2 and the second stream is scaled by k 2 = 2 ? ? 1 ? 1 2 - ? 2 2 .

Abstract: A scanner for a keyboard device having a reflective surface for each key has a sensor associated with each key that includes an LED and a photo-transistor. The LED is turned ON for a first measurement, followed by a second measurement with the LED turned off, and a subtraction of the second measurement from the first yields an illumination value for a key x. The LEDs and associated photo-transistors are sequentially enabled in groups of n, thereby eliminating optical interference. Each key x has associated correction parameters of LinRest(x) associated with illumination value with the key in the rest (up) position, LinDown(x) associated with illumination value with the key in the down position, TrebErr(x) associated with the reflectivity effect of one adjacent key(x+1), and BassErr(x) associated with the reflectivity effect of another adjacent key(x?1).

Abstract: A clock selector operative on two clocks operating on different domains and responsive to a SELECT input provides a transition from a first clock to a second clock, and from a second clock to a first clock with a dead zone therebetween. The delay is provided by a doublet register having a first register coupled to a second register, the two registers operative on one of the clock domains. Additionally, a clock selector is operative on two clocks which are each accompanied by a clock availability signal where the state machine provides a variety of states to create a dead zone between selections, and to bring the state machine to a known state until a clock signal is again available.

Abstract: A preamble detector for a plurality of streams of baseband digitized signals has a plurality of preamble processors, each preamble processor coupled to an input and generating an output. Each preamble processor has an input coupled to a first delay, the output of the first delay coupled to a second delay generating an output. The first and second delay are substantially equal to a preamble part. A first multiplier generates an output from a conjugated output of the second delay output and a first delay output. A second multiplier generates an output from a conjugated first delay output and an input stream. The first and second multiplier outputs are accumulated over an interval, and the complex output of the accumulator is formed into a magnitude, thereby generating the output of each preamble processor. The outputs of the preamble processors are summed and compared to a threshold to generate a preamble detect.

Abstract: An OFDM symbol comprises information subcarriers which carry the information to be transmitted, accompanied by edge subcarriers, which are selected to minimize the PAPR of the transmitted signal. The selection of edge subcarriers which minimizes PAPR enables either higher power transmission for the same information content, or lower power consumption for the same transmitted symbol power.

Abstract: A reduced complexity maximum likelihood decoder receives a stream of symbols Y and channel estimate H. A transformation converts Y and H into Z and R by computing matrix R, such that the product of R and Q produces matrix H. A second transformation column-swaps matrix H to form H?, thereafter generating Q? and R? subject to the same constraints as was described for Q and R. Transformed variables Z and Z? are formed by multiplying Y by QH and Q?H, respectively. Table entries with Z and R and Z? and R? have entries of all possible x2 accompanied by estimates of x1 derived from x2 and Z, and similar entries of all possible x1 accompanied by estimates of x2 derived from x1 and Z?. Hard and soft decisions are made by finding the minimum distance metric of the combined entries of the first and second table.

Abstract: A re-transmit processor for a wireless communication system includes a pointer memory which contains pointers associated with particular packet data in a host memory. The re-transmit processor directs data associated with said pointers to be applied to a media access controller, which optionally contains an encryption function, the output of which is coupled to a block buffer and to an output interface. Upon receipt of a transmission request, the host memory locations associated with the pointers are read and the data directed to the media access controller, which adds a header, a CRC, and optionally encrypts the data, thereafter placing it in the block buffer and the output interface. Upon provision of the packet data to the MAC, the associated pointer is initialized to a FREE or UNUSED value, and upon receipt of an acknowledgement of the packet accompanied by a packet identifier from a receiving station, the packet associated with the packet identifier is removed from the block buffer.

Abstract: A transmit-receive switch has a transmit port, an antenna port, and a receive port. A first switch couples the transmit port to the antenna port when a signal TxON is asserted. A LOW_BAND signal indicates the selection of a lower band of frequencies. A tuning structure is formed by a second and third switch in series which couple the antenna port to ground through a first capacitor when TxON and LOW_BAND are both asserted, and LOW_BAND may be provided to one or more such tuning structures for multi-band frequency operation. A second capacitor couples the antenna port to ground when a fourth switch is enabled. An inductor couples the antenna port to the receive port. A third capacitor is placed across the receive port and ground. A fifth switch is closed when TxON is asserted. The first through fifth switches can be a CMOS FET with an isolated substrate coupled to ground through an associated resistor.

Abstract: A wireless receiver generates quadrature baseband signals which are sampled by a high speed analog to digital converter (IQ ADC) and also uses a receive signal strength indicator (RSSI) which is sampled by an RSSI analog to digital converter (RSSI ADC). The RSSI ADC signal is processed in combination with an end of packet signal to generate a first threshold from the average RSSI signal after the end of packet with the receive amplifiers set to a comparatively high level. A second threshold is generated by adding a threshold increment to the first threshold, and when the RSSI crosses the second threshold, the IQ ADC is taken out of a standby mode and placed in an active mode for the duration of the packet. The RSSI ADC is enabled from end of packet until packet detection by the baseband processor, and placed in standby at other times.

Abstract: A sensor for force is formed from an elastomeric cylinder having a region with apertures. The apertures have passageways formed between them, and an optical fiber is introduced into these passageways, where the optical fiber has a grating for measurement of tension positioned in the passageways between apertures. Optionally, a temperature measurement sensor is placed in or around the elastomer for temperature correction, and if required, a copper film may be deposited in the elastomer for reduced sensitivity to spot temperature variations in the elastomer near the sensors.

Abstract: A Reed Solomon decoder utilizes re-configurable and re-usable components in a granular configuration which provides an upper array and a lower array of repeated Reconfigurable Elementary Units (REU) which in conjunction with a FIFO can be loaded with syndromes and correction terms to decode Reed Solomon codewords. The upper array of REUs and lower array of REUs handle the Reed Solomon decoding steps in a pipelined manner using systolic REU structures. The repeated REU includes the two registers, two Galois Field adders, a Galois Field multiplier, and multiplexers to interconnect the elements. The REU is then able to perform each of the steps required for Reed-Solomon decoder through reconfiguration for each step using the multiplexers to reconfigure the functions. In this manner, a reconfigurable computational element may be used for each step of the Reed-Solomon decoding process.

Abstract: An apparatus for the deposition of a variable thickness coating onto the inside of a cylindrical tube comprises a variable pressure gas, an cathode coaxially positioned within the cylinder, and a voltage source applied between the cathode and cylindrical tube, which functions as an anode. A radial plasma arc is generated between the anode and cathode at a starting point on the cylinder, and the plasma arc travels down the central axis of the cylinder, providing a helical deposition region on the inside of the cylinder. Selection of the combination of cathode material and gas enable the plasma to generate ionic material which is deposited on the anodic cylinder in the region of the plasma. By varying the pressure of variable pressure gas for each helical path, it is possible to vary the composition of this deposition film.

Abstract: A scanner for a keyboard device having a reflective surface for each key has a sensor associated with each key that includes an LED and a photo-transistor. The LED is turned ON for a first measurement, followed by a second measurement with the LED turned off, and a subtraction of the second measurement from the first yields an illumination value for a key x. The LEDs and associated photo-transistors are sequentially enabled in groups of n, thereby eliminating optical interference. Each key x has associated correction parameters of LinRest(x) associated with illumination value with the key in the rest (up) position, LinDown(x) associated with illumination value with the key in the down position, TrebErr(x) associated with the reflectivity effect of one adjacent key(x+1), and BassErr(x) associated with the reflectivity effect of another adjacent key(x?1).

Abstract: A wireless signal processor for use in identifying a maximum Carrier to Noise Interference Ratio (CINR) associated with a plurality of received OFDMA subcarriers has a candidate generator for forming a plurality of candidate values from a particular set of received subcarriers by forming candidate values based on the received subcarriers in combination with possible integer preamble offsets and possible preamble values. A candidate evaluator selects which of the possible preamble values and integer frequency offset values have the maximum CINR, and provides the maximum CINR with IFO and preamble index as outputs.

Abstract: A Liquid Metal Ion Thruster (LMIT) has a substrate having a plurality of pedestals, one end of the pedestal attached to the substrate, and the opposing end of the pedestal having a tip, the pedestals having grooves and the substrate also having grooves coupled to each other and to a source of liquid metal. An extractor electrode positioned parallel to the substrate and above the pedestal tips provides an electrostatic extraction field sufficient to accelerate ions from the tips of the pedestals through the extractor electrode. A series of focusing electrodes with matching apertures provides a flow of substantially parallel ion trajectories, and an optional negative ion source provides a charge neutralization to prevent space charge spreading of the exiting accelerated ions. The assembly is suitable for providing thrust for a satellite while maintaining high operating efficiencies.

Abstract: Methods, systems, and apparatus, including computer program products, for restoring audio signals. A data sequence of samples representing an audio signal is received. Multiple filter coefficients are defined for a filter, and a current sample in the data sequence is selected to be processed. The filter coefficients are updated based on a previous sample preceding the current sample in the data sequence and a filtered value determined by the filter for the previous sample. A filtered value for the current sample is determined using the filter with the updated filter coefficients. The filtered value of the current sample is used to determine whether the current sample has been corrupted by impulsive noise, for example, a crackle.