Abstract: Embodiments of a base station and method for mitigating interference in a sectorized wireless communication network are generally described herein. Other embodiments may be described and claimed. In some embodiments, some partitions of subchannels are configured in accordance with the distributed subcarrier permutation scheme for use within each sector of a base station, and one or more partitions of subchannels is configured in accordance with the contiguous subcarrier scheme for use within each sector of the base station.

Abstract: A DTV transmitting system includes a pre-processor, a block processor, and a trellis encoder. The pre-processor pre-processes enhanced data by expanding the enhanced data at an expansion rate of 1/H. The block processor includes a first converter, a symbol encoder, a symbol interleaver, and a second converter. The first converter converts the expanded data into symbols. The symbol encoder encodes each valid enhanced data bit in the symbols at an effective coding rate of 1/H. The symbol interleaver interleaves the encoded symbols, and the second converter converts the interleaved symbols into enhanced data bytes. The trellis encoder trellis-encodes the enhanced data outputted from the block processor.

Abstract: A channel equalizer includes an overlap unit, an estimator, a calculator, a compensator, and a save unit. The overlap unit overlaps a group of data packets in a broadcast signal. The group data packets include a head, a body, and a tail, and a known data sequence is periodically included in the body. The estimator estimates a CIR of each data region the body using the known data sequence, and it further estimates CIRs of data regions in the head or tail using the CIRs obtained for the data regions in the body. The calculator calculates equalization coefficients based on the CIRs estimated by the estimator, and the compensator compensates channel distortion of the overlapped data using the equalization coefficients. The save unit saves the compensated data.

Abstract: A method for processing a plurality of symbol streams is provided. The method includes receiving a first symbol stream, wherein the first symbol stream has a corresponding first number of retransmissions. The method further includes receiving a second symbol stream, wherein the second symbol stream has a corresponding second number of retransmissions. The method further includes selecting the first symbol stream for decoding, if the first number of retransmissions is greater than the second number of retransmissions.

Abstract: A transmitter portion 14 includes a control circuit 32, a driver circuit 33, and a wave detector circuit 35. The control circuit 32 generates control signals Vp, Vn based on a pulsed transmission signal So. The driver circuit 33, which is supplied with a battery voltage Vb, generates an output signal Sa to be sent to an antenna 13 based on the control signals Vp, Vn. The wave detector circuit 35 outputs a detection signal Sk having a voltage proportional to the level of the output signal Sa (transmission power level). The control circuit 32 changes the pulse widths of the control signals Vp, Vn based on the voltage level of the detection signal Sk. As a result, electric power consumption is reduced and enlargement of an apparatus is suppressed while maintaining the transmission power level constant.

Abstract: A frame rate converting apparatus includes a pan/tilt determining unit which determines whether an image is in a pan/tilt state on the basis of information related to motion of the image detected by a motion detecting unit for each frame of a moving image, a moving distance setting unit which sets 0 as a moving distance of an image with respect to a frame the image of which is not determined as an image in a pan/tilt state by the pan/tilt determining unit, which calculates a moving distance of an image from the information related to the motion of the image detected by the motion detecting unit with respect to a frame the image of which is determined as an image in a pan/tilt state, and which sets the obtained moving distance as a moving distance of the image, and a prediction image generating unit which generates a prediction image necessary for frame rate conversion on the basis of the moving distance of the image set for each frame by the moving distance setting unit.

Abstract: Method and apparatus for determining a downlink channel response in an orthogonal frequency division multiplexing access (OFDMA) system. The method and apparatus uses the uplink quality indication channel for determining the downlink channel response, or uses round trip pilot relay channel sounding. The uplink quality indication channel may comprise modified mini-tiles. The subscriber station using round trip pilot relay channel sounding sends composite transponder pilots after receiving the DL pilots.

Abstract: The disclosure relates to a method for receiving a data signal by NR receiving antennas. The data signal undergoes, before transmission, a channel coding and is transmitted on NT antennas each transmitting a portion of this signal. Upon reception the transmission channel between the transmitting antennas and the receiving antennas is estimated. The method of the aforementioned type involves at least one iteration for improving an estimation of the received signal according to the received signal and involves a preceding estimation of said received signal, comprising the following steps: filtering this received signal; determining an interference affecting the received signal while furnishing an estimated interference; subtracting this estimated interference form the filtered signal whereby obtaining an improved signal; equalizing this improved signal and furnishing an equalized signal, and; estimating, from this equalized signal, the emitted data signal, called the estimated signal.

Abstract: A synchronization module for an orthogonal frequency-division multiplexing (OFDM) receiver system including a signal combination module that generates N combination signals that correspond to N received signals by performing at least one of weighted combining and selection and equal-gain-combining (EGC) on the N signals. A weighted signal generator module generates N weighted signals based on the N combination signals. N is an integer greater than one.

Abstract: A method and apparatus for reducing the complexity of waveform correlation computations used by a multicode receiver is described herein. One exemplary multicode receiver includes a despreading unit, channel estimator, and waveform correlation calculator. The despreading unit despreads a received multicode signal to generate despread symbols. The channel estimator estimates channel coefficients associated with the despread symbols. The waveform correlation calculator determines waveform correlations between the transmitted symbols in successive processing windows that span two or more symbol periods and that overlap in time. To reduce the computational complexity associated with computing waveform correlations, the calculator may reuse channel coefficients and/or net channel correlations for multiple symbol periods and/or processing windows.

Abstract: Embodiments include methods and apparatus for verifying the detection of a correlation peak, which may represent an acquisition of a received acquisition code symbol sequence. The method includes determining a series of coherently-aligned peaks from a series of correlation peaks. Determining the plurality of coherently-aligned peaks includes correcting a frequency offset and a phase offset for each of the plurality of correlation peaks. A coherent match filter process is performed on the plurality of coherently-aligned peaks. A detection of the correlation peak may be verified when the match filter result exceeds a threshold.

Abstract: Alternative direct sequence spread spectrum symbol to chip mappings and methods for generating the same for use in a direct sequence spread spectrum wireless protocol and embedded in a transceiver chip used by wireless subsystems are provided. The present invention discloses alternative symbol to chip mappings that are orthogonal or nearly orthogonal to the N/2 unused chip sequences defined by a standard transmission protocol. The present invention is advantageous because it provides for an increased number of users and better reliability for wireless subsystems operating in increasingly overcrowded frequency bands. Other advantages of the present invention include a reduction in the negative effects of clear channel assessment including delayed or cancelled signal transmission and interference for wireless subsystems that transmit time-sensitive data.

Abstract: A method and apparatus for a nonlinear feedback control system is disclosed, such as for electrical and electronic systems, for pre-distorting a nonlinear device. A nonlinear feedback control system includes a nonlinear device having a first input and a first output. A detection stage is in communication with the first output of the nonlinear device. A derivation stage is in communication with the detection stage, and the derivation stage is in communication with the first input of the nonlinear device.

Abstract: In one embodiment, a method includes receiving, from a decoder connected to a wireless receiver for communication with a remote apparatus, first error data that indicates a current error rate that corresponds to a first inbound data packet received from the remote apparatus. Based in part on the first error data, it is determined whether the remote apparatus should increase a current signal to noise ratio. If so, then a first outbound data packet is sent to an encoder connected to a wireless transmitter. The first outbound data packet includes first link conditioning request data that indicates a current signal to noise ratio for one or more data packets received from the remote apparatus based at least in part on the first error data. The remote apparatus increases signal to noise ratio of transmissions in response to receiving the outbound data packet.

Abstract: Embodiments of a multiple-input multiple-output (MIMO) communication system and methods for beamforming using polar-cap codebooks are generally described herein. Other embodiments may be described and claimed. In some embodiments, beamforming is based on codewords of a polar-cap codebook which represents deviations in the channel with respect to codewords of a full-manifold codebook.

Abstract: Embodiments of an OFDM receiver and methods for decoding OFDM symbols of two or more data streams with reduced multiplication operations are generally described herein. Other embodiments may be described and claimed. In some embodiments, one or more terms of a modified L2-squared-norm cost function are precomputed and stored for predetermined complex symbol values of one or more tones of OFDM symbols prior to performing a searching process. During the searching process, the cost function is computed using the precomputed terms and received data symbols using shifting and adding operations, rather than multiplication operations. In other embodiments, non-L2-squared-norm cost functions are used.

Abstract: Systems and/or methods are disclosed for generating a waveform that comprises a plurality of elements by using a Fourier transform and/or an inverse Fourier transform. The waveform that comprises the plurality of elements may be transmitted by transmitting, sequentially in time, the plurality of elements. In some embodiments, the Fourier transform and/or inverse Fourier transform comprises a Fast Fourier Transform and/or Inverse Fast Fourier Transform and the waveform that comprises the plurality of elements may be transmitted by using, sequentially in time, the plurality of elements to modulate a sinusoidal waveform.

Abstract: A method for correcting gain imbalance error, phase imbalance error and DC offset errors in a transmitter having an OFDM-based I/Q modulator is disclosed. The method employs a compensator prior to the I/Q-modulator to compensate for the gain and phase imbalance and DC offset. The compensator is efficiently updated with the estimated values of gain and phase imbalance and DC offsets obtained by performing the DFT operation in the digital baseband domain while sending a pair of orthogonal test tones to the modulator's inputs from a digital baseband chip, then down converting the RF modulated signal through a nonlinear device and a bandpass filter to a baseband signal, and finally sampling it using an A/D. The delay mismatch, which is mainly generated by lowpass filters between the I and Q branches, is also minimized in this method.

Abstract: Communications systems and/or methods are disclosed that can provide extreme privacy, cognitive radio capability, robustness to fading and interference, communications performance associated with M-ary orthonormal signaling and/or high multiple-access capacity. Embodiments can use spread-spectrum waveforms that are featureless, devoid of chipping and devoid of cyclostationary signatures, statistically indistinguishable from thermal noise and able to cognitively fit within any available frequency space (narrow-band, broad-band, contiguous, non-contiguous). Some embodiments maintain all desirable features of classical direct-sequence spread-spectrum communications while providing new dimensions that are important to communications systems. Embodiments of the invention can provide M-ary orthonormal signaling with chipless spread-spectrum waveforms to provide extreme covertness and privacy.

Abstract: Various embodiments of the present invention provide systems and methods for decoding encoded information. For example, a decoder including a branch metric calculator that conditionally calculates a branch metric based on either an actual input or a saturated input. Such a branch metric calculator is operable to receive an actual input, and to compare the actual input with an expected range. At times, the aforementioned comparison yields a comparison result indicating that the actual input is outside of the expected range. A first branch metric associated with a first branch is calculated. Where the first branch has an expected value representing a boundary of the expected range, calculating the first branch metric is done using the saturated input. Further, a second branch metric associated with a second branch is calculated. Where the second branch has an expected value representing something other than a boundary of the expected range, calculating the second branch metric is done using the actual input.