A communication system that minimizes the transmission of pilot symbols while ensuring real-time channel tracking and symbol detection. The system employs a multiple-input multiple-output (MTMO) transmitter-receiver pair where there are many more receive antennas than transmit antennas. Communication occurs over a wide band RF channel via orthogonal frequency division multiplexing (OFDM) that employs a large number of sub-carriers.

Techniques to manage dwell times for pilot rotation are described. An apparatus may comprise a memory configured to store a data structure with a set of modulation and coding schemes (MCS) available to an orthogonal frequency division multiplexing (OFDM) system, each MCS having an associated pilot dwell time. The apparatus may further comprise a processor circuit coupled to the memory, the processor circuit configured to identify a MCS to communicate a packet using multiple subcarriers of the OFDM system, and retrieve a pilot dwell time associated with the MCS from the memory, the pilot dwell time to indicate when to shift a pilot tone between subcarriers of the multiple subcarriers during communication of the packet. Other embodiments are described and claimed.

The present application describes a computer-implemented method for configuring a front end including receiving a first signal and a second signal containing interference; characterizing the receive channel using the first tone; processing the compensated first signal using an infinite impulse response filter based on the characterized receive channel to generate an interference cancelling signal; and coupling the interference cancelling signal to the second signal to generate an interference cancelled receive signal. The present application also describes a computer-implemented apparatus for a front end.

The present disclosure discloses example method, apparatus, and storage medium for improving multi-user multiplexing performance. One example method includes configuring base sequence identifiers by a network device for a plurality of terminals by using radio resource control (RRC) signaling, where there is no orthogonality between base sequences indicated by the base sequence identifiers of the plurality of terminals. Sounding reference signal (SRS) detection is performed on the plurality of terminals based on a quasi-orthogonal sequence, to obtain channel information for sending an SRS by each terminal. Channel prediction is performed based on the channel information of each terminal, to obtain a channel prediction result of each terminal.

An image processing apparatus for determining a focused output image in a passive autofocus system is configured to retrieve a set of input images and compute a baseline estimate for at least one input image. The baseline estimate represents image structures in the input image. The image structures have a length scale larger than a predetermined image feature length scale. The image processing apparatus is further configured to compute a set of output images, wherein each output image of the set of output images is computed based on one of a different input image of the set of input images and the at least one baseline estimate for the different input image and the at least one baseline estimate for a respective different input image. The image processing apparatus is further configured to determine one output image of the set of output images as the focused output image.

To enable use of channel related information more suitable for propagation environment. A wireless communication apparatus according to an example aspect of the present invention includes: a memory storing instructions; and one or more processors configured to execute the instructions to: acquire correlation information regarding correlation between first channel related information generated through channel estimation for a first estimation period and second channel related information generated through channel estimation for one or more estimation periods before the first estimation period; and perform control for a statistic of channel related information, based on the correlation information.

Methods and apparatus of channel estimation using time-domain parameter extraction are disclosed. The wireless channel can be modeled by a multipath model with a limited number of parameters in the continuous time domain. Extracting the time-domain parameters and then reconstructing the channel yields channel estimates that have better accuracy. Time-domain parameter extraction also has lower computational complexity than existing methods.

A mechanism for mutually coupling multiple antennas for transmission in a wireless communication environment, wherein, for a received or transmitted radio signal a precoding matrix is created that includes artificial mutual antenna coupling coefficients and processing the received or transmitted radio signal using the created precoding matrix.

The present invention concerns a method and device for demodulating received symbols using a turbo-demodulation scheme comprising an iterative channel equalization and wherein an iterative channel decoder is used in the turbo-demodulation scheme, characterized in that the iterative channel decoder performs a first iterative process named iterative decoding process, the turbo-demodulation performing a second iterative process named iterative demodulation and decoding process, at each iteration of the second iterative process, the iterative channel decoder executing plural iterations in order to decode bits from which symbols are derived from. The iterative channel decoder: memorizes at the end of the iterations of the first iterative process, the variables used internally by the iterative channel decoder, reads the memorized variables at the following iteration of the second iterative process.

System and method of timing recovery for recovering a clock signal with reduced interference with clock phase correction by an adaptive equalizer. The equalizer in the timing recovery loop is dynamically adapted to the current channel characteristics that vary over time. Upon a good Signal-to-Noise Ratio (SNR) being achieved, a selected set of the tap weights of the equalizer filter are frozen or set to smaller values, while others continue to adapt and the timing recovery loop continues the clock recovery process. Thereby, the adaptation of equalization can be adjusted to attenuate the equalization filter's effect on clock delay correction by limiting the adaptation time or speed relative to those of the entire timing recovery loop.