The present invention discloses a method for configuring an operation mode of a remote transceiver unit connected to an access node via a communication line, the remote transceiver unit being operable in at least two operation modes: a Time Division Duplex, TDD, mode and a full duplex, FDX, mode; the method comprising, by the access node: a) obtaining a channel characteristic derived from channel measurements performed over the communication line, b) determining the operation mode of the remote transceiver unit as the FDX mode or the TDD mode based on the channel characteristic; c) transmitting an indication indicating the determined operation mode to the remote transceiver unit.

The embodiments provide a cryptography key for two communicating devices that is based on information known only to the devices. The information may only be determined by the devices. Each device determines the information without communicating key information related to the encryption key with the other. Channel characteristic reciprocity between the devices allows creation of identical keys in each device. Each device sends a signal to the other device at the same power level based on the distance between the devices. The power level may be set to result in a target receive power level at the other device. Each device samples the received signal, generates sampling results, creates a key based on the sampling results and a threshold power level, and utilizes the key. The threshold power level may be based on the target receive power level, or a median power determined from the sampling results.

A communication device includes: a wireless transceiver configured to communicate with another communication device through a wireless channel; and at least one processor configured to execute instructions to: a) estimate at least one first channel response of the wireless channel based on a predetermined signal received from the another communication device; and b) predict a second channel response based on the at least one first channel response by an extrapolation method for signal transmission to the another communication device at a time instant where no channel estimation is performed.

Disclosed herein are an apparatus for analyzing a transmitter identification (TxID) signal and a method using the apparatus. The apparatus for analyzing the TxID signal includes a demodulator for decoding the bootstrap of a received signal; a cancellation unit for performing a host signal cancellation process for the received signal, thereby generating a host-signal-cancelled received signal; a correlator for calculating a correlation value between a signal corresponding to the host-signal-cancelled received signal and a signal corresponding to a TxID sequence; and a TxID profile analyzer for generating information about a channel between a transmitter corresponding to the TxID signal and a receiver using the correlation value.

Some demonstrative embodiments include apparatuses systems and/or methods of ranging measurement. For example, an apparatus may include circuitry and logic configured to cause a first wireless communication station (STA) to receive from a second STA a sounding transmission for a range measurement of a range between the first STA and the second STA; to determine a channel response estimation based on the sounding transmission from the second STA; to determine a timing value based on the channel response estimation; and to transmit a feedback message to the second STA, the feedback message including the timing value.

There is provided an estimation device including an acquisition unit that acquires a channel estimation value for each combination of all of a plurality of combinations between a plurality of transmission antenna elements included in a base station and a plurality of reception antenna elements included in a mobile station; and an estimation unit that calculates a channel impulse response for each combination of all of the plurality of combinations between the plurality of transmission antenna elements and the plurality of reception antenna elements using the channel estimation values, and that estimates power delay profile by averaging, over all the combinations of the plurality of combinations between the plurality of transmission antenna elements and the plurality of reception antenna elements, power values for the respective combinations that are calculated from the calculated channel impulse responses for the respective combinations.

In a digital communication system there is provided a method for OFDM channel estimation that jointly considers the effects of coarse timing error and multipath propagation. The method uses an iterative channel estimation technique, which considers the practical scenario of fractional timing error and non-sample space echo delays. The method does not require channel state information such as second-order statistic of the channel impulse responses or the noise power. Moreover, timing error can be conveniently obtained with the proposed technique. Simulation shows that, when comparing OFDM channel estimation techniques under DOCSIS 3.1 realistic channel conditions, the proposed algorithm significantly outperforms conventional methods.

Adaptive windowing of insufficient cyclic prefix (CP) for joint minimization of intersymbol interference (ISI) and adjacent channel interference (ACI) is provided. The proposed subcarrier specific windowing scheme improves the signal-to-interference ratio (SIR) even when the cyclic prefix (CP) is insufficient. Average optimal window lengths depend only on the power density profiles (PDPs), and although instantaneous optimal window lengths depend on users' channel impulse responses (CIRs), fluctuation is little. Therefore, subcarrier specific windowing outperforms fixed windowing, even with outdated window lengths in the case of powerful interferers.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for transmitting signals with a high data rate. In some implementations, an apparatus includes a first digital signal processor outputting first data at a first data rate. A second digital signal processor outputting second data at a second data rate. A filter circuitry receiving and up-sampling the first and second data. Additionally, the apparatus includes a combiner circuit that receives the first up-sampled data and the second up-sampled data, the combiner circuit combining the first and second up-sampled data to provide a multiplexed output, the multiplexed output having a third data rate that is greater than the first data rate or the second data rate.

The embodiments provide cryptography that is performed in each of two communicating devices and is based on information known only to the devices. The information is determined in each of the devices at the time of communications. Each of the devices determines the information without communicating key information related to the encryption key with each other. Channel characteristic reciprocity between the two devices allows creation of identical keys in each device. Each of the devices sends a first setup signal to the other device, receives a second setup signal from the other device, where the second setup signal may be a looped back version of the first setup signal, samples the second setup signal, generates sampling results, creates a key based on the sampling results, and utilizes the key to exchange one or more secure data signals with the other device.