In a transmitter apparatus, a known reference signal is superimposed on top of a data signal that is typically not known a priori to a receiver and the combined signal is transmitted. At a receiver, an iterative channel estimation and equalization technique is used to recover the reference signal and the unknown data signal. In the initial iteration, the known reference signal is recovered by treating the data signal as noise. Subsequent iterations are used to improve estimation of received reference signal and the unknown data signal.

A data receiver configured to receive a signal having at least two partial data packets, the data receiver being configured to estimate a state of a transmission channel, to obtain first channel state information, to demodulate a first set of received symbols from different data packets, to obtain a first set of received encoded bits, wherein the data receiver is configured to decode the first set of received encoded bits to determine, a first set of estimated encoded bits which corresponds more likely to a first set of transmitted encoded bits than the received encoded bits, and to map the first set of estimated bits to estimated transmission symbols using a mapping rule matching a transmitter-side mapping rule to obtain a first set of estimated transmission symbols, and to determine second channel state information using the first set of estimated transmission symbols.

In accordance with one or more embodiments, a transmission device includes a receiver configured to receive an interfering signal via an antenna. A controller is configured to generate interference data based on the interfering signal. A communications interface is configured to send the interference data to a network element of a network and further configured to receive an allocation of a plurality of guided electromagnetic wave resource blocks. A transmitter is configured to generate electromagnetic signals conveying data, in accordance with the allocation of the plurality of guided electromagnetic wave resource blocks. A coupler configured to generate guided electromagnetic waves in response to the electromagnetic signals, wherein the guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive, within a subframe, a plurality of sidelink control channel signals providing scheduling information for a plurality of sidelink shared channel signals that are also received within the subframe. The UE may determine to use one or more of the plurality of sidelink control channel signals as pilot signals for decoding the plurality of sidelink shared channel signals. The UE may decode the plurality of sidelink shared channel signals based at least in part on the plurality of sidelink control channel signals as pilot signals.

In a transmitter apparatus, a known reference signal is superimposed on top of a data signal that is typically not known a priori to a receiver and the combined signal is transmitted. At a receiver, an iterative channel estimation and equalization technique is used to recover the reference signal and the unknown data signal. In the initial iteration, the known reference signal is recovered by treating the data signal as noise. Subsequent iterations are used to improve estimation of received reference signal and the unknown data signal.

The present disclosure relates to a state feedback decoder based channel estimating method including: calculating a first output bit when an input bit is 0 and a second output bit when an input bit is 1 using convolution encoder state information received from a determining unit; configuring a first virtual pilot and a second virtual pilot through modulation by receiving the first output bit and the second output bit; deinterleaving an i-th (here, i refers to a natural number corresponding to the number of OFDM symbols from 1) OFDM symbol; estimating a first channel and a second channel based on the first virtual pilot and the second virtual pilot using an output value in accordance with the deinterleaving result and calculating a first mean square error (MSE) and a second MSE; and comparing the calculated first MSE and second MSE to determine an input bit having a lower MSE as a reception bit by the determining unit and updating and feedbacking the convolution encoder state information using the determined reception bit.

Provided are methods of operating a wireless communication system. The methods include determining first resource mapping patterns of a first physical channel used to generate virtual pilot signals so as to perform downlink channel estimation, based on state information of user equipment (UE) in every first period. The first physical channel is mapped onto resource elements adjacent to resource elements onto which pilot signals are mapped, in a time-frequency resource area (TFRA) of a downlink signal based on the determined first resource mapping patterns. A downlink signal of which resource mapping is completed is then transmitted to the UE.

In accordance with one or more embodiments, a transmission device includes a receiver configured to receive an interfering signal via an antenna. A controller is configured to generate interference data based on the interfering signal. A communications interface is configured to send the interference data to a network element of a network and further configured to receive an allocation of a plurality of guided electromagnetic wave resource blocks. A transmitter is configured to generate electromagnetic signals conveying data, in accordance with the allocation of the plurality of guided electromagnetic wave resource blocks. A coupler configured to generate guided electromagnetic waves in response to the electromagnetic signals, wherein the guided electromagnetic waves propagate, without requiring an electrical return path, along a surface of a transmission medium of a distributed antenna system.

Methods, systems, and devices for wireless communication are described. A wireless communications system may support techniques for using non-staggered reference signals to increase the efficiency of the system and reduce the complexity of channel estimation. A base station may schedule a transmission to a user equipment (UE) including pilot tones mapped to a first symbol and a second symbol. In some cases, the pilot tones on the first and second symbols may be non-contiguous, and the base station may scramble the pilot tones on the first and second symbols according to the same scrambling sequence. In other cases, the pilot tones on the first and second symbols may be contiguous, and the pilot tones may be scrambled according to the same or different scrambling sequences. These techniques may result in reduced complexity for interference estimation and channel estimation at a UE.

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.