Embodiments described herein provide a system for transmitting high efficiency long term training field (HE-LTF) symbols for multiple wireless spatial streams over a wireless channel. An advanced P-matrix design is used to construct HE-LTF symbols that are processed by a receiver such that channel properties such as channel estimates or carrier phase error are determined prior to receiving all HE-LTF symbols. Tone multiplexing of wireless spatial stream is also used to transmit multiple spatial streams based on an assignment of sets of spatial streams to sets of tones available for transmission, increasing the throughput of the transmission system. The advanced P-matrix design and tone multiplexing are used in combination to achieve calculate channel properties before receiving all HE-LTF symbols while minimizing power fluctuation among the high efficiency short training field symbol and the HE-LTF symbols.

An OFDM communication system, includes: a smoothing filter; an equalizer; processors; and a memory containing instructions causing the processors to perform steps of: providing to the smoothing filter a plurality of channel response estimates, each corresponding to a symbol and a channel; receiving a plurality of filtered channel response estimates, each corresponding to a value of the channel response estimate; calculating a plurality of error vectors, each having a plurality of error values, each error value being a difference between the channel response estimate and the filtered channel response estimate; obtaining a mean error vector having a plurality of mean error values, each corresponding to a subcarrier for all symbols; calculating a power of each subcarrier based on the mean error values of the mean error vector; comparing the power of each subcarrier to a threshold power; and adjusting the bandwidth of the smoothing filter based on the comparison.

An apparatus, method and computer program is described comprising receiving data at a receiver of a transmission system; using a receiver algorithm to convert data received at the receiver into an estimate of the first coded data, the receiver algorithm having one or more trainable parameters; generating an estimate of first data bits by decoding the estimate of the first coded data, said decoding making use of an error correction code of said encoding of the first data bits; generating a refined estimate of the first coded data by encoding the estimate of the first data bits; generating a loss function based on a function of the refined estimate of the first coded data and the estimate of the first coded data; updating the trainable parameters of the receiver algorithm in order to minimise the loss function; and controlling a repetition of updating the trainable parameters by generating, for each repetition, for the same received data, a further refined estimate of the first coded data, a further loss function and further updated trainable parameters.

Communication is performed by using an uplink control channel of a configuration matching each shortened TTI. A user terminal according to the present invention includes: a transmission section that transmits uplink control information via an uplink control channel by using a shortened TTI configured by a smaller number of symbols than symbols of a normal TTI; and a control section that controls the transmission of the uplink control information, and the control section transmits the uplink control information by using a resource block subjected to frequency hopping between slots in the second TTI, and maps a demodulation reference signal on at least one symbol that configures the slots.

Methods related to wireless communication systems and the transmission of code blocks on such systems are provided. A wireless communication device interleaves a plurality of code block segments in time and frequency. The segments are interleaved by mapping a first code block segment of the plurality of code block segments to a first resource located at a first time and a first frequency, wherein the first code block segment is associated with a first code block, and mapping a second code block segment of the plurality of code block segments to a second resource based on at least one of the first time or the first frequency of the first resource and a code block proximity parameter, wherein the second code block segment is associated with a second code block different from the first code block. The device then transmits the plurality of interleaved code block segments. Other features are also claimed and described.

A method of operation for an Ethernet transceiver is disclosed. The method includes operating the Ethernet transceiver in a data mode, and triggering a fast retrain sequence of steps based on trickling error information. The triggering includes detecting error information, averaging the detected error information over a time interval to generate the trickling error information, comparing the averaged detected error information to a selected threshold value, and initiating the fast retrain sequence of steps based on the comparing.

Device, methods and systems for aspects of channel estimation for orthogonal time frequency space (OTFS) modulation in wireless systems are described. In an aspect, a method for wireless communication may include receiving, using multiple receive antennas, from a number of user devices, non-orthogonal pilots wherein at least some transmissions of the non-orthogonal pilots from GT different user devices overlap in at least some time and frequency resources, estimating individual pilots from the number of user devices by computing a pilot separation filter for each antenna, and estimating the wireless channel at time and frequency resources used by the non-orthogonal pilots by filtering the receiving signal at the multiple receiver antennas.

A method for a user equipment (UE) to receive physical downlink control channels (PDCCHs) is provided. The UE receives configuration information for a first control resource set that includes a number of symbols in a time domain and a number of resource blocks (RBs) in a frequency domain, configuration information indicating a first number of N.sub.bundle,1 frequency-contiguous RB s, and a PDCCH in the first control resource set in a number of frequency distributed blocks of N.sub.bundle,1 RBs. The UE assumes that a demodulation reference signal associated with the reception of the PDCCH has a same precoding over the N.sub.bundle,1 RBs. A method for constructing a search space to reduce a number of channel estimations that the UE performs for decoding PDCCHs, relative to conventional search spaces, is also provided.

Disclosed are a signal transmission method and a base station, the method: generating a PCRS used in order to remove phase noise from a downlink signal; mapping the PCRS at predetermined intervals on a region, in which a data channel is mapped, in a downlink resource region; and transmitting the PCRS to a terminal.

A user terminal receives a downstream link data signal, a demodulation reference signal for demodulating the downstream link data signal, and a downstream link signal including a downstream link control signal; calculates a channel estimation value using the demodulation reference signal; demodulates the downstream link data signal using the channel estimation value; and demodulates the downstream link control signal using the channel estimation value calculated from the demodulation reference signal mapped to a symbol before a symbol to which the downstream link control signal is mapped in a sub-frame.