Embodiments of a method and an apparatus for wireless communications are disclosed. In an embodiment, a method for wireless communications involves encoding bits in a Physical Layer Protocol Data Unit (PPDU) using a basic bandwidth that is smaller than a signal bandwidth, wherein the bits are duplicated within the PPDU, and transmitting the PPDU with duplicated bits in accordance with a power spectrum density (PSD) limit.

A system includes the transmitter that transmits a first adjustment signal obtained based on a first parameter, detects, based on an output potential of the transmitter, a second parameter that is among values settable to the first parameter and sets the second parameter and the receiver that receives the first adjustment signal from the transmitter and acquire a second adjustment signal by adjusting the first adjustment signal based on a third parameter, sets the third parameter, counts the number of errors of the second adjustment signal based on a difference between the second adjustment signal and the test pattern, determines, based on the number of errors of the second adjustment signal, the second parameter to be set in the transmitter and controls the connection of the terminal resistor to the input terminal based on the second parameter.

In a wireless frame transmission method by an access point (AP) in a wireless LAN system, according to an embodiment of the present invention, a wireless frame, comprising a signaling field and a data field, is generated in the AP, wherein the signaling field comprises a first signaling field (SIG A field), having first common control information about a plurality of STAs, and a second signaling field (SIG B field) having individual control information for each of the plurality of STAs. The second signaling field comprises a common field, having second common control information about the plurality of STAs, and an individual field following the common field and having individual control information for each of the STAs. An individual field (a first individual field) of the second signaling field being transmitted from a particular 20 MHz band (a first band) can comprise: resource allocation information about one or more first band STAs to which resources are allocated in the first band; and resource allocation information about one or more second band STAs to which resources are allocated from another 20 MHz band (a second band) other than the first band. Therefore, the length of the first individual field can be set to be the same as the length of the individual field (second individual field) of the second signaling field being transmitted from the second band.

A method for transmitting a frame by an AP includes generating and transmitting a radio frame including a signaling field and a data field. The signaling field includes a SIG A field including first common control information for the plurality of STAs, and a SIG B field including specific control information for each of the plurality of STAs. The second signaling field includes a common field including second common control information for the plurality of STAs, and a specific field following the common field, including the specific control information for each of the plurality of STAs, and the specific field of the second signaling field transmitted in a specific 20-MHz band includes resource allocation information for one or more first-band STAs to which resources are allocated in the first band, and resource allocation information for one or more second-band STAs to which resources are allocated in another 20-MHz band.

A universal asynchronous receiver/transmitter includes a transmission register to include information to be transmitted, a receive register to include information received, a frame error checking circuit to evaluate contents of the receive register for a frame error, and control logic. The control logic is to route the contents of the transmission register to the receive register. The control logic is to, during transmission of the contents of the transmission register through the reprogrammable pin to the receive register, modify a bit inversion register to yield modified contents to be provided to the receive register. The modified contents are to cause a frame error. The control logic is to determine whether the frame error checking circuit detected the frame error.

In an ultra-wideband (UWB) receiver, a received UWB signal is periodically digitized as a series of ternary samples. During a carrier acquisition mode of operation, the samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (CIR) are developed. When a start-of-frame delimiter (SFD) is detected, the best CIR estimate is provided to a channel matched filter (CMF). During a data recovery mode of operation, the CMF filters channel-injected noise from the sample stream. Both carrier phase errors and data timing errors are continuously detected and corrected during both the carrier acquisition and data recovery modes of operation. The phase of the carrier can be determined by accumulating the correlator output before it is rotated by the carrier correction. By comparing the carrier phases of two receivers separated by a known distance, d, the angle of incidence, , of the signal can be determined. One or more receivers may be adapted to use multiple antennae, thus reducing the total number of receivers relative to the total number of antennae.

A signal detector device and method includes a quadrature demodulator configured to receive an input signal, a first reference signal, and a second reference signal in quadrature with the first reference signal, the quadrature demodulator further configured to produce a plurality of output signals from the input signal and the first and the second reference signal, the plurality of output signals indicating the amplitude and phase of the input signal, and one or more inverting circuits, the inverting circuits having a first and a second programmable output polarity, the plurality of output signals being output by the quadrature demodulator when the inverting circuits are set to the first programmable output polarity, the plurality of output signals being inverted and output by the quadrature demodulator when the inverting circuits are set to the second programmable output polarity.

In an ultra-wideband (UWB) receiver, a received UWB signal is periodically digitized as a series of ternary samples. During a carrier acquisition mode of operation, the samples are continuously correlated with a predetermined preamble sequence to develop a correlation value. When the value exceeds a predetermined threshold, indicating that the preamble sequence is being received, estimates of the channel impulse response (CIR) are developed. When a start-of-frame delimiter (SFD) is detected, the best CIR estimate is provided to a channel matched filter (CMF). During a data recovery mode of operation, the CMF filters channel-injected noise from the sample stream. Both carrier phase errors and data timing errors are continuously detected and corrected during both the carrier acquisition and data recovery modes of operation. The phase of the carrier can be determined by accumulating the correlator output before it is rotated by the carrier correction. By comparing the carrier phases of two receivers separated by a known distance, d, the angle of incidence, , of the signal can be determined. One or more receivers may be adapted to use multiple antennae, thus reducing the total number of receivers relative to the total number of antennae.

A method for transmitting a frame by an AP includes generating and transmitting a radio frame including a signaling field and a data field. The signaling field includes a SIG A field including first common control information for the plurality of STAs, and a SIG B field including specific control information for each of the plurality of STAs. The second signaling field includes a common field including second common control information for the plurality of STAs, and a specific field following the common field, including the specific control information for each of the plurality of STAs, and the specific field of the second signaling field transmitted in a specific 20-MHz band includes resource allocation information for one or more first-band STAs to which resources are allocated in the first band, and resource allocation information for one or more second-band STAs to which resources are allocated in another 20-MHz band.

Methods and apparatus for calibrating a polar transmitter are provided. Calibration circuitry is configured to generate an adjustment signal that communicates an amplitude modulation/phase modulation (AMPM) delay value to AMPM delay circuitry that is configured to delay, based at least on the AMPM delay value, output of a signal by digital signal processing circuitry (DSP) in the polar transmitter. The calibration circuitry includes signal generation circuitry, estimation circuitry, and delay circuitry. The signal generation circuitry is configured to generate a calibration signal to control the polar transmitter to generate a calibration transmit signal. The estimation circuitry is configured to receive a result signal that is based on the calibration transmit signal and estimate the AMPM delay value based at least on the result signal. The delay circuitry is configured to provide an adjustment signal to communicate the estimated AMPM delay value to the AMPM delay circuitry.