Abstract: Systems and methods for improved communications using tunneled direct link setup are described herein. The systems and methods relate to discovery, link setup, channel switching, multicasting, link selection, and quality of service implemented in conjunction with tunneled direct link setup.

Abstract: A wireless communication apparatus of the present invention comprises a plurality of branches, a tap output combining section, an adaptive blind processing section and a diversity combining section. Each of the plurality of branches comprises a tap processing section generates a tap output signal and a received signal vector on a basis of a received signal and a tap coefficient in a space diversity method. The tap output combining section calculates by linking the tap output signal as a tap output combination signal. The adaptive blind processing section generates the tap coefficient by an adaptive blind processing on a basis of the tap output combination signal and the received signal vector. The diversity combining section performs a diversity combination of the tap output signals. The adaptive blind processing section uses an evaluation condition so that the tap output combination signal be minimal.

Abstract: This disclosure provides systems, methods, and apparatus for receiving paging messages in fast fading scenarios. In one aspect, a method of demodulating a paging message during an assigned time slot by a wireless communications apparatus operating in an idle mode is provided. The method includes determining, in anticipation of the assigned time slot, an expected time position corresponding to a path of a pilot signal having a greater signal strength relative to other pilot signals. The method further includes assigning a first demodulation element to demodulate the pilot signal with reference to the expected time position and assigning a second demodulation element to demodulate the pilot signal with reference to a time offset from the expected time position. Other aspects, embodiments, and features are also claimed and described.

Abstract: Disclosed are methods and a device for Multi-resolution PMI Feedback. In one implementation, a user equipment finds a rank 1 or rank 2 Precoding Matrix Indicator based on the signal channel matrix and interference covariance matrix, defines an error vector, obtains an orthonormal basis for the projection matrix, finds the (M?1)-dimensional vector from a codebook (e.g., oversampled Discrete Fourier Transform) with the minimum Euclidean distance, and sends a feedback representing to the base station regarding the vector that it found in the codebook.

Abstract: A system that incorporates the subject disclosure may include, for example, a process that includes adjusting a filter in electrical communication between an input terminal and a demodulator. The filter is applied to an information bearing signal, e.g., to mitigate interference, received at the input terminal, resulting in a filtered signal. An error signal is received, indicative of errors detected within information obtained by demodulation of a modulated carrier of the filtered signal. A modified filter state is determined in response to the error signal and the filter is adjusted according to the modified filter state, e.g., to improve mitigation of the interference. Other embodiments are disclosed.

Abstract: An integrated circuit includes a first port for conducting a first plurality of signals, a second port for conducting a second plurality of signals, a data path coupled between the first port and the second port, a controller, and a processor having an input and an output. In a first mode, the controller causes the data path to conduct at least one signal received on the first port to the second port. In a second mode, the controller controls the processor to output signals to the second port.

Abstract: A method for processing a radio signal includes: receiving a signal on two antennas; demodulating the signal using first and second independent signal paths that are synchronized by symbol number; maximum ratio combining branch metrics from the two receiver paths; and using the combined branch metrics to produce an output, wherein the receiver paths include an arbitration scheme. A receiver that implements the method is also provided.

Abstract: Compressive sampling is used to generate pilot symbols to be transmitted over an array of antennas in a MIMO wireless communications device. A pilot symbol is transmitted over the array of antennas according to a spatially randomized antenna transmission function that randomly changes across the array of antennas. The randomized antenna transmission function may randomly select/deselect antennas and/or randomly change amplitude and/or phase of the pilot symbol transmission. Channel estimates can be constructed at a receiver based on the spatially randomized pilot symbols that were transmitted.

Abstract: A receiving apparatus for receiving signals in a transmission system transmitted based on a frame structure including signaling data and payload data. The receiving apparatus includes a receiver configured to receive a transmission signal, a frame demapper configured to demap signaling data blocks and payload data patterns from the frames of the frame structure of the received transmission signal, wherein a signaling data block is assumed to include a number of data corresponding to a number of a signaling data pattern, wherein the signaling data patterns are split into n signaling data portions, n being a positive integer, in which n signaling portions are mapped onto n or less frames, and a demodulation decoder is configured to separately demodulate and decode the signaling data blocks and payload data patterns to obtain signaling data and payload data.

Abstract: Techniques for handling fingers with large delay spread through utility optimization are described. A first signal may be received, through a finger of a plurality of fingers in a receiver, at a time that is later than a reference time after a reference signal is received by a reference finger of the plurality of fingers. The reference signal may be included in an on-time group corresponding to a cell. The first signal may be included in a late group corresponding to a virtual cell. The first signal and the reference signal may be compared to one another. Based on the comparing, it may be determined whether to wait for additional signals in the late group or process the signals in the on-time group.

Abstract: Power control for devices having multiple transmit antennas are disclosed, including power control methods for Physical Uplink Control Channel (PUCCH) and Sounding Reference Signal (SRS) transmissions for a wireless transmit/receive unit (WTRU). The PUCCH and SRS power control methods include selecting a multiple input multiple output (MIMO) mode and changing the power of the PUCCH or SRS transmission based on the selected MIMO mode. Another power control method estimates an antenna gain imbalance (AGI) for a WTRU having at least two transmit antennas. The AGI is based on measuring a Reference Signal Received Power (RSRP) on each transmit antenna. Each transmit antenna is then scaled by an AGI scaling factor based on the estimated AGI.

Abstract: Systems and methods for detecting data in a multiple input/multiple output signal. The method includes receiving a first signal associated with a first data value and a second signal associated with a second data value. A distance value between the received second signal and each possible second data value is calculated. Coordinates for a hypothetical first signal in light of a first possible second data value are calculated, and the first coordinate value is quantized to a nearest constellation point. A distance value between the received second signal and each possible second data value is calculated using the calculated constellation points. A determination is made of a log-likelihood ratio based on the determined distance values.

Abstract: An integrated circuit includes a component calculator configured to compute at least one component value of a highly programmable analog-to-digital converter (ADC) from at least one application parameter, and a mapping module configured to map the component value to a corresponding register setting of the ADC based on at least one process parameter, wherein the integrated circuit produces digital control signals capable of programming the ADC. In a specific embodiment, the component calculator uses an algebraic function of a normalized representation of the application parameter to approximately evaluate at least one normalized ADC coefficient. The component value is further calculated by denormalizing the normalized ADC coefficient. In another specific embodiment, the component calculator uses an algebraic function of the application parameter to calculate the component value.

Abstract: The present invention relates to a receiver in a 2×2 Line of Sight Multiple Input Multiple Output, LoS MIMO, system. The receiver is arranged to estimate a first (?1) and a second (?2) signal on the basis of a first (r1(t)) and a second (r2(t)) signal received from respective first and second transmitters (Tx1,Tx2). Said received signals (r1(t), r2(t) comprises a first and second signal. The receiver comprises a first Phase Locked Loop (11), PLL, and a second PLL (12), which are arranged to respectively determine a first (In1) and second (In2) demodulated signal from the first (r1(t)) and the second (r2(t)) received signals. The receiver further comprises an equalizer (13) which is arranged to estimate the first (?1) and second (?2) signals from the demodulated signals (In1,In2).

Abstract: Systems are provided for searching for a codeword from a plurality of codewords in a codebook for use in precoding, for example, as used in a multiple-input multiple-output (MIMO) transmission system. Dimension reduction techniques may be utilized to reduce the complexity and enhance the efficiency of the codebooks search. Null-spaces of an optimal codeword and codewords in a codebook may be computed. Distance values may be computed based on the null=spaces of the codewords. A codeword may be selected from the codebook based on a minimum distance value from the optimal codeword.

Abstract: A method for transmitting a sounding reference signal from a user equipment in a MIMO antenna wireless communication system. The method includes receiving sounding reference signal setup information from a base station, the sounding reference signal setup information including an initial cyclic shift value nSRScs and an initial transmissionComb parameter value kTC; setting an interval between cyclic shift values corresponding to each antenna port based on the initial cyclic shift value, to reach a maximum interval; setting a transmissionComb parameter value corresponding to a specific one of the antenna ports to a value different from the initial transmissionComb parameter value if the initial cyclic shift value is a previously set value and the number of antenna ports is 4; and transmitting the sounding reference signal to the base station through each antenna port by using the set cyclic shift value and transmissionComb parameter value.

Abstract: In accordance with an embodiment, there is provided a method comprising receiving, at a receiver, a desired signal and an interfering signal, wherein the interfering signal was transmitted with a modulation unknown to the receiver; identifying a likely modulation corresponding to the modulation with which the interfering signal was transmitted; and decoding the desired signal using a modulation dependent multiple-input multiple output (MIMO) detection, wherein the modulation dependent MIMO detection is based at least in part on the identified likely modulation corresponding to the modulation with which the interfering signal was transmitted, wherein the modulation dependent MIMO detection includes maximum likelihood (ML) detection.

Abstract: Certain aspects of the present disclosure relate to techniques for generating likely demodulation candidates using Vector Candidate Sampling (VCS). VCS is used to generate high likelihood candidates for Multiple Input Multiple Output (MIMO) demodulation that approaches optimal maximum a posteriori (MAP) performance with reasonable complexity. A receive data vector is recorded corresponding to a signal received at a MIMO receiver. A plurality of likely candidates are determined for MIMO demodulation via VCS, based at least on the receive data vector. Determining the likely candidates may include perturbing the receive data vector for each candidate based on a pre-determined perturb vector, and estimating a corresponding transmit data vector based at least on the perturbed receive data vector for the candidate and an estimator matrix, wherein the likely candidate comprises the estimated data vector.

Abstract: A receiver is configured to use a first part of a received signal and a second part of the received signal to determine, respectively, a first estimate and a second estimate of the channel. The first and second parts carry information for decoding the received signal in a first protocol and in a second protocol, respectively. A final estimate of the channel is performed from the first and the second estimates. The final estimate is then used for decoding the data in the received signal according to one of the protocols. A carrier frequency offset from a set of symbols occurring prior to preamble symbols is determined and is corrected for decoding the preamble symbols. The corrected preamble symbols are then used for estimating the channel. In one embodiment, the carrier frequency offset is determined for the multiple antenna packet format used in the 802.11n standard.

Abstract: A diversity control method and a wireless communication apparatus which are capable of saving time and electricity consumed for diversity control if an approximation pattern approximating to a synchronization pattern appears in a reception signal during acquisition of the reception strength of every antenna by selecting any one of a plurality of antennas as a receiving antenna in every selection cycle, detection operation of a synchronization signal is continued regardless of the above described selection cycle.

Abstract: A digital subscriber line access multiplexer (DSLAM) configured to couple to a first subscriber line and a second subscriber line, wherein the DSLAM comprises at least one transmitter configured to transmit a first signal onto the first subscriber line in a first time slot, transmit a second signal onto the second subscriber line in the first time slot, wherein the first and second signals are linearly related and are intended for a first customer premise equipment (CPE), transmit a third signal onto the second subscriber line in a second time slot, and transmit a fourth signal onto the first subscriber line in the second time slot, wherein the third and fourth signals are linearly related and are intended for a second CPE.

Abstract: A base station does not transmit any reference signal (RS) for channel measurement in a subframe in which transmission of an RS collides with transmission of a synchronization signal or a broadcast signal or in a resource block including the synchronization signal or the broadcast signal in the subframe. A user equipment assumes that any RS for channel measurement is not transmitted in a subframe or in a resource block when transmission of an RS collides with transmission of a synchronization signal or a broadcast signal in the subframe or in the resource block.

Abstract: A system and method to perform Full Duplex (FD) Space Division Duplex (SDD) communication using a Self-Interference Cancelling (SIC) precoder that applies different antenna phase shifts and amplitude scales to the transmitted signals to force them to be in the null space of the selected receive antennas. Thus, a wireless communication unit can place nulls at each of its receive antennas digitally at baseband for one or more frequency bands. The SIC precoder may be computed based on the self-interference channel from the transmit chain(s) to the receive chain(s). Different SIC precoders may be adaptively selected and stored digitally for different frequency bands. Subsequent single or multi-user precoder can be applied in concatenation with the SIC precoder to transmit signals to one or more users while receiving signals from one or more users simultaneously over the same frequency band.

Abstract: Systems and methods are provided for decoding signal vectors in multiple-input multiple-output (MIMO) systems, where the receiver has received one or more signal vectors based on the same transmitted vector. The receiver linearizes each received signal vector using one or more zero-forcing, MMSE, or other suitable linear equalizers. The components of the equalized signal vectors may be combined using maximum-ratio combining to form the components of a combined equalized signal vector. The components of the combined equalized signal vector may then be decoded individually using a linear decoder.

Abstract: A method implemented in a base station used in a wireless communications system is disclosed. The method comprises having a codebook including a plurality of precoding matrices, precoding data with one of the plurality of precoding matrices, and transmitting, to a user equipment, the precoded data, wherein each precoding matrix W satisfies W=W(1)W(2), where first matrix W(1) is chosen from first codebook (1), and second matrix W(2) is chosen from a second codebook. Other apparatuses, systems, and methods also are disclosed.

Abstract: Systems and methods are described using a Hermetic Transform, as well as related transforms, for applications such as directional reception and/or transmit of signals using phased-array devices and systems. The systems and methods an include identifying a direction of arrival for a mobile communicating device. The systems and methods also include the use of a noise conditioning matrix.

Abstract: An electronic device including a first transceiver configured to process a first carrier, a second transceiver configured to process a second carrier, a switch, a baseband processor configured to process a first baseband signal and a second baseband signal, which are processed respectively by the first transceiver and the second transceiver, an antenna connected through the switch in association with some of a plurality of reception paths with respect to the first carrier, and a reception path configured to provide the second transceiver with the first carrier received via the antenna connected through the switch to the second transceiver.

Abstract: Systems, methods, apparatuses, and computer program products for an interleaved multi-beam acquisition waveform providing concurrent beam selection, automatic gain control (AGC) and automatic frequency correction (AFC) are provided. The access point (AP) may send an acquisition waveform on multiple beams, then return and retransmit an AFC on the multiple beams thus interleaving beam switching with the acquisition and frequency correction waveforms. AGC correction can be deferred until the end, relying on the fact that the transmitter may be detected at close range using a one of the multi-beams that is attenuated.

Abstract: A method for frequency performing offset estimation and channel estimation includes performing frequency offset estimation on the received data, and obtaining a frequency offset estimation result when interference signals in received data are not obtained, After the interference signals in the received data are obtained, the method includes performing frequency offset estimation on the received data according to the interference signals, and obtaining a frequency offset estimation result. Channel estimation is performed on the received data according to the frequency offset estimation result, and a channel estimation result is obtained. Interference signals are obtained according to the frequency offset estimation result and the channel estimation result, where the interference signals are used as parameters of the frequency offset estimation.

Abstract: A communications method uses simultaneously at least two receivers to reduce a need for data retransmissions. When using multiple receivers it is enough that at least one of the receivers outputs a correct bit set which are preferably checked by Cyclic Redundancy Check (CRC). The method comprises the following to be performed in a radio modem: a) receiving the same sample of a signal in a first receiver and in a second receiver; and in response to the same sample b) obtaining a first bit set from the first receiver and a second bit set from the second receiver; and c) determining whether the first bit set or the second bit set is a correct bit set. A retransmission request is sent only when the first and second bit sets are erroneous. This reduces latencies in the transmission. One can change receivers depending on the radio frequency (RF) circumstances.

Abstract: A precoding scheme to accommodate user equipment (UEs) having higher Doppler speeds. In such transmission schemes, a different precoding matrix is applied to each orthogonal frequency division multiplex (OFDM) symbol in the transmission stream. Additionally, a downlink control message format is defined to handle assignment of multiple different transmission schemes using the same message format. The downlink control message format includes a control element in one of the message fields along with a set of parameters specifically applicable to the assigned transmission scheme. Based on the value of this control element, the UE sets the specific transmission scheme and determines a set of interpretation rules uniquely associated with that transmission scheme. Using the interpretation rules, the UE is able to read the set of parameters as applied to the selected transmission scheme.

Abstract: A method for transmitting and receiving a signal and an apparatus for transmitting and receiving a signal are disclosed. The method includes receiving the signal from a first frequency band in a signal frame including at least one frequency band, demodulating the received signal by an orthogonal frequency division multiplexing (OFDM) method and parsing the signal frame, acquiring a symbol stream of a service stream from the at least one frequency band included in the parsed signal frame, demapping symbols included in the symbol stream and outputting the demapped symbols to sub streams, multiplexing the output sub streams and outputting one bit stream, and deinterleaving and error-correction-decoding the output bit stream.

Abstract: A method for symbol detection includes assigning a received symbol to at least one particular candidate symbol of a set of candidate symbols of a finite candidate symbol alphabet based on a metric between the received symbol and the at least one particular candidate symbol, the metric comprising contributions with respect to channel-based information and contributions with respect to a priori information.

Abstract: This invention is related to a low-complexity MIMO detector in a wireless communication system with near optimal performance. An initial symbol estimation is performed for a received symbol vector. The soft information of the received symbol vector can be more accurately calculated using every candidate symbol vector of a combined set of candidate symbol vectors, wherein the combined set is generated based on the initial estimation. By combining aspects of both the linear detection and the ML detection, the complexity of the proposed detector becomes orders of magnitude lower than that of a ML detector, but the performance is very close to that of an ML detector.

Abstract: Techniques are provided which may be implemented using various methods and/or apparatuses in a device comprising a receiver to scan a spectral band of a received signal comprising a desired signal contribution to determine whether signal data associated with at least a sub-band of the spectral band further comprises at least one undesired signal contribution. In response to determining that the signal data comprises at least one undesired signal contribution, the mobile station may initiate at least one notch filter to affect the undesired signal contribution in subsequent signal data associated with the received signal.

Abstract: A communication circuit and a communication device are provided. The communication circuit includes first, second, and third RF transceivers, first and second baseband transceivers, and first and second modem circuits. The first and second RF transceivers are configured to down-convert first and second RF signals for MIMO. The third RF transceiver is configured to down-convert a third RF signal for a second telecommunication technology. The first baseband transceiver is configured to digitize the down-converted first RF signal to output a first baseband signal. The second baseband transceiver is configured to digitize one of the down-converted second or third RF signals according to a selection signal to output a second baseband signal. The first modem circuit is configured to digitally process the first and second baseband signals using the MIMO technology. The second modem circuit is configured to digitally process the second baseband signal using the second telecommunication technology.

Abstract: A MIMO transmitter including an interleaving system for parsing encoded bits to a plurality of spatial streams and a plurality of interleavers to interleave bits for spatial streams such that at least a first spatial stream uses a first stream interleaver that interleaves with a pattern distinct from a second stream interleaver interleaving for a second spatial stream.

Abstract: An exemplary system comprises at least one antenna, first and second signal paths, and an N-plexer. The antenna may be configured to receive first and second diversity receive signals. The antenna is further configured to transmit first and second diversity transmit signals. The first signal path may have a frequency converter configured to downconvert the first diversity receive signal to an intermediate frequency and to upconvert the first diversity transmit signal to a radio frequency. The second signal path may have a frequency converter configured to downconvert the second diversity receive signal to an intermediate frequency and to upconvert the second diversity transmit signal to the radio frequency. The N-plexer may be configured to provide the first and second diversity receive signals to a cable and to provide from the cable the first and second diversity transmit signals to the first signal path and the second signal path, respectively.

Abstract: The present invention relates to a method including signalling by a receive node at least one first transmission rank r to a transmit node, where 1?r ?R, wherein R is a maximum available rank for a transmission, and at least one predefined precoding matrix corresponds to the first transmission rank r, determining by the transmit node a second transmission rank r? for transmitting data from the transmit node to the receive node, where 1?r? ?R, defining at least two subsets of precoding matrices for at least one of the at least one first transmission rank r, selecting one of the at least two subsets of precoding matrices in accordance with a channel quality estimate for a radio channel, and signalling the selected one subset of precoding matrices, wherein the selected one subset of precoding matrices is associated with said the at least one predefined precoding matrix.

Abstract: A station in a wireless communication system includes a processor circuitry configured to form at least a first plurality of data streams and a second plurality of data streams, and a digital precoder configured to receive the first plurality of data streams and the second plurality of data streams. The wireless station can further include a plurality of radio frequency (RF) beamforming chains connected to the digital precoder and configured to form at least one RF envelope, wherein the digital precoder is configured to steer a plurality of digital beams within the at least one RF beam envelope, the digital beams forming a plurality of spatially distinct paths for the first plurality of data streams and a plurality of spatially distinct paths for the second plurality of data streams, and a plurality of antennas operably connected to the RF beamforming chains.

Abstract: A multi-input, multi-output pre-filter improves operation of a multi-input receiver by shortening the effective memory of the channel with a set of FIR filters. The coefficients of these FIR filters can be fashioned to provide a variety of controls by the designer, for example, the value of the effective memory.

Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus determines whether a timing offset between a PCC and an SCC possibly exceeds a threshold. In addition, the apparatus switches an amplifier gain utilizing one of a first set of gain states or a second set of gain states based on the determination that the timing offset possibly exceeds the threshold. The first set of gain states includes a first number of gain states, and the second set of gain states includes a second number of gain states less than the first number of gain states.

Abstract: A receiving station receives an orthogonal frequency division multiplexing (OFDM) symbol via a shared medium, the OFDM symbol comprising a first set of frequency components modulated with preamble information and a second set of frequency components modulated with information. The receiving station processes sampled values of the received OFDM symbol based on channel characteristics estimated from the first set of frequency components to decode information encoded on a first subset of the second set of frequency components. The receiving station processes sampled values from the first symbol based on channel characteristics estimated from the first set of frequency components and the first subset of the second set of frequency components to decode information encoded on a second subset of the second set of frequency components.

Abstract: Provided are a method of receiving downlink data and a machine type communication (MTC) device using the same. The MTC device according to the present invention which has a plurality of antennas includes a reception signal processing module that receives a downlink reference signal for each antenna from a base station, estimates reception signal quality with respect to the downlink reference signal for each antenna, and selects the antenna to receive a downlink signal in accordance with the reception signal quality with respect to each antenna.

Abstract: In one embodiment, a method for performing antenna diversity combining for digitally broadcast radio signals includes generating a first signal quality metric for a first signal obtained from an incoming digitally broadcast radio signal received in a first signal path, and similarly generating a second signal quality metric for a second signal obtained from the radio signal received in a second signal path. Then the first and second signals from these paths can be coherently combined based on the signal quality metrics to obtain a combined frequency domain symbol. In some embodiments, this combined frequency domain symbol may be remodulated to a time domain symbol. Also in some embodiments N tuners can be daisy chained to generate a final output that is either a frequency domain symbol of combined sub-carriers, soft bits to a forward error correction (FEC) decoder, or a remodulated time domain symbol. As a further possibility, each of the N tuners can use a different local oscillator (LO) frequency.

Abstract: A method and apparatus for achieving China Mobile Multimedia Broadcasting (CMMB) diversity reception are disclosed. The method includes: acquiring respective Analogue-to-Digital Converter (ADC) data of two antennas; respectively conducting a synchronization and Fast Fourier Transform (FFT) operation on the ADC data of the two antennas, acquiring delay information about the two antennas, and according to an operation result, selecting a signal to noise ratio (SNR) configuration parameter; according to the delay information, conducting delay compensation on the operated data; and according to the selected SNR configuration parameter, merging the data of the two antennas on which the delay compensation is conducted, and outputting the data.

Abstract: A method and apparatus are provided for transmitting a source signal including a plurality of binary sequences to NR receiving antennas, where NR is no lower than 2. The method implements, for at least one first binary sequence of the source signal, pre-filtering for focusing a signal to be transmitted on at least one of the reception antennas, referred to as the target antenna. The target antenna and the associated focus pre-filtering step are selected according to a value of the first binary sequence intended for being considered as received. The method also includes transmitting the pre-filtered signal.

Abstract: An apparatus and method for generating a codebook in a wireless communication system are disclosed. The codebook generation apparatus includes a processor for generating a covariance matrix of a channel between the transmitting end and a receiving end, using a unitary matrix including a first vector corresponding to at least one quantized dominant singular singular vector of the channel and a second vector corresponding to at least one basis vector of a null space of the first vector, and transforming a predefined first codebook by applying the covariance matrix of the channel to the first codebook.

Abstract: The present disclosure provides a method of generating codebook in a wireless communication system with multiple antenna arrays, as well as a wireless communication system, base station and terminal using the codebook for communication. The method comprises steps of: providing a basic codebook which contains multiple pre-coding matrices; and assigning phase offsets to certain pre-coding matrices in the basic codebook to form a codebook with phase offset. The feedback overhead from a client to a base station side is reduced and a good precision of feedback for multi-antenna array is kept by applying the method of generating codebook and using the generated codebook in the wireless communication system, base station and terminal.

Abstract: A method for processing a preamble of a data unit transmitted via a communication channel includes receiving a signal via a plurality of antennas, applying a plurality of distinct steering vectors to the received signal to generate a plurality of respective outputs, and using the plurality of outputs to perform at least one of carrier sensing and symbol timing synchronization associated with the preamble.