In a mobile communication system, a mobile communication apparatus in a vehicle includes a selected resource antenna permitting communication using a selected resource, establishing wireless communication with a target communication apparatus. The mobile communication system includes a propagation path characteristic acquirer section and a resource selector section. The propagation path characteristics acquirer section acquires propagation path characteristics information in association with a future communication position, the propagation path characteristics information being about propagation path characteristics between (i) the target communication apparatus and (ii) a reference antenna equal to the selected resource antenna in antenna characteristics including an antenna format. The resource selector section, based on the propagation path characteristics information, selects a resource to be used in communication at the future communication position before the selected resource antenna of the mobile communication apparatus comes to be placed at the future communication position.

A decoder for determining an estimate of a vector of information symbols carried by a signal received through a transmission channel represented by a channel matrix is provided. The decoder includes a block division unit configured to divide the vector of information symbols into two or more sub-vectors, each sub-vector being associated with a block level; two or more processors configured to determine, in parallel, candidate sub-vectors and to store the candidate sub-vectors in a first stack. Each processor is configured to determine at least a candidate sub-vector by applying a symbol estimation algorithm and to store each candidate sub-vector with a decoding metric and the block level associated with the candidate sub-vector. The decoding metric is lower than or equal to a decoding metric threshold. A processor among the two or more processors is configured to determine at least a candidate vector from candidate sub-vectors stored in the first stack, the candidate vector being associated with a cumulated decoding metric and to update the decoding metric threshold from the cumulated decoding metric.

An ultra-wideband (UWB) wireless communication system, comprises a first wireless apparatus; a second wireless apparatus that participates in a first ranging sequence with the first wireless apparatus; and a transmission channel between the first and second wireless apparatuses that transmits data of the first ranging sequence. At least one of the first wireless apparatus or second wireless apparatus generating at least one channel impulse response (CIR) and determining from the at least one CIR whether the transmission channel includes a line-of-sight channel. A special purpose processor reduces a current performance level of at least one of the first and second wireless apparatuses during a second ranging sequence in response to a determination that the transmission channel includes the line-of-sight channel.

Disclosed is an electronic device, including a housing, a first communication circuit disposed in the housing and configured to support omnidirectional wireless communication, a second communication circuit disposed in the housing and configured to support directional wireless communication using beamforming, a processor disposed in the housing and operatively coupled to the first communication circuit and the second communication circuit, and a memory disposed in the housing and operatively coupled to the processor. The processor may be configured to receive at least one first radio signal through a communication channel from an external device capable of supporting the omnidirectional wireless communication and the directional wireless communication using the first communication circuit, determine a state of the communication channel based on at least part of the at least one first radio signal, and activate the second communication circuit based on at least part of the determined state of the communication channel wherein the second communication circuit is configured to receive a second radio signal from the external device.

Systems, methods, and devices enable coexistence of traffic for collocated transceivers. Methods may include transmitting a baseband training signal via a transmit path of a wireless communications device, obtaining a plurality of samples of the baseband training signal via a receive path of the wireless communications device, and generating a plurality of weighted averages based on the plurality of samples. Methods may further include generating an estimated amplitude and an estimated phase for at least one spur frequency of the wireless communications device based, at least in part, on the plurality of weighted averages.

A transmission station device includes a training signal generation unit, a CP addition unit, and a transmission beamforming unit that performs transmission beamforming processing in a time domain using a transmission weight for removing inter-antenna interference. A reception station device includes a CP removal unit, a channel estimation unit, and an equalization unit that performs equalization processing for removing inter-symbol interference in a frequency domain using a reception weight. Either of the transmission station device or the reception station device is provided with a weight calculation unit that calculates the transmission weight and the reception weight based on the channel response, an effective CIR length calculation unit that calculates an effective CIR length between antennas, and a CP length setting unit that sets, to the CP length, a maximum CIR length among the CIR lengths of respective items of the reception weight.

This disclosure provides channel estimation methods and apparatuses. One method includes: determining Ps initial sample channel matrices that indicate channel states, where the Ps initial sample channel matrices include P1 first sample channel matrices and Ps-P1 second sample channel matrices, the P1 first sample channel matrices are determined based on a previous sample channel matrix or a given reference signal, and Ps is an integer greater than 1, and determining a channel matrix based on the Ps initial sample channel matrices, and obtaining a channel estimation result. Because the P1 initial sample channel matrices in the Ps initial sample channel matrices are determined based on the previous sample channel matrix or the given reference signal, an initial channel estimation result may be provided as an iterative initial sample channel matrix.

A method for receiving, at a communications station which has a plurality of antennas, messages from a plurality of users in wireless communication with the communications station, comprising the steps of: (i) receiving, from the users, using the plurality of antennas, time-slotted information chunks formed from the messages of the users, wherein the information chunks are free of any encoded user-identifiers representative of the users transmitting the messages; (ii) after receiving all of the information chunks, estimating vectors representative of respective communication channels between the antennas and the users based on the received information chunks; (iii) grouping the information chunks based on the estimated vectors to form clusters of the information chunks respectively associated with the users; and (iv) recovering the messages of the users from the clusters of the information chunks.

Systems, methods, and devices reduce and mitigate spurs that may occur in transmit waveforms of wireless communications devices. Methods include receiving a plurality of samples of a baseband transmission and generating, using a processing device, an estimated amplitude and an estimated phase of a spur component of the baseband transmission based on the received plurality of samples, the spur component being a spectral spike in a transmit waveform. Methods further include generating, using the processing device, a canceling signal configured to cancel the estimated amplitude and estimated phase of the spur component, and canceling the spur component of the baseband transmission by combining the canceling signal with a transmission of at least a portion of a data packet.

A decoder for determining an estimate of a vector of information symbols carried by a signal received through a transmission channel represented by a channel matrix is provided. The decoder includes a block division unit configured to divide the vector of information symbols into two or more sub-vectors, each sub-vector being associated with a block level; two or more processors configured to determine, in parallel, candidate sub-vectors and to store the candidate sub-vectors in a first stack. Each processor is configured to determine at least a candidate sub-vector by applying a symbol estimation algorithm and to store each candidate sub-vector with a decoding metric and the block level associated with the candidate sub-vector. The decoding metric is lower than or equal to a decoding metric threshold. A processor among the two or more processors is configured to determine at least a candidate vector from candidate sub-vectors stored in the first stack, the candidate vector being associated with a cumulated decoding metric and to update the decoding metric threshold from the cumulated decoding metric.