摘要:
A data transmission system transmitting data using a relay is provided. The relay selects a transmission terminal from a plurality of terminals connected to a base station. During a first time slot, the base station transmits base station data to the relay and the transmission terminal transmits terminal data to the relay. The relay transmits the terminal data to the base station and transmits the base station data to the transmission terminal during a second time slot.
摘要:
A main hub, a sub hub, and a sensor node communicating in a wireless body area network (WBAN) including at least one sub hub, and a communication method thereof, are provided. A communication method of the main hub, includes assigning a beacon slot to the sub hub. The method further includes receiving, from the sub hub, a beacon signal based on the beacon slot. The method further includes verifying whether the sub hub includes data to be transmitted to the main hub based on the beacon signal. The method further includes receiving, from the sub hub, the data based on a result of the verification.
摘要:
A method and a target node for preventing collisions between networks communicating based on a carrier sense multiple access/collision avoidance (CSMA/CA) scheme, are provided. The method includes synchronizing an object network with a neighboring network. The method further includes allocating, to the object network, a slot index based on a number of the networks, and a contention window (CW) size. The method further includes setting, for the object network, a back-off counter value based on the CW size. The method further includes reducing the back-off counter value based on a channel state of the object network, and the slot index. The method further includes transmitting data related to the neighboring network based on the back-off counter value.
摘要:
An apparatus and method for hierarchical modulation and demodulation in a wireless communication network are provided. A hierarchical modulation apparatus may map information bits to a plurality of levels based on a predetermined level map, may generate an error verification code for each of the levels based on the information bits mapped to the levels, may generate coded information bits for each of the levels, and may map bits in a predetermined position among the coded information bits, to Pulse-Position Modulation (PPM) symbols in a sequence of the levels.
摘要:
An ultra low power super-regenerative receiver is provided. The ultra low power super-regenerative receiver includes a bit synchronizer configured to use a value sampled from a signal output from a super-regenerative oscillator to estimate a pulse-level position having a maximum amplitude value in a single period of a received symbol, a frame synchronizer configured to combine a plurality of pulse-level positions determined based on the estimated pulse-level position, and detect a predetermined bit sequence using the plurality of pulse-level positions combined, the frame synchronizer being configured to perform frame synchronization, and a data detector configured to detect data using the plurality of pulse-level positions determined after the frame synchronization is completed.
摘要:
Provided is a receiver for feeding back channel information, which includes a channel vector measuring unit to measure channel vectors corresponding to a plurality of receiving antennas, respectively, that receive a plurality of data streams, a candidate codebook vector selecting unit to select at least two candidate codebook vectors from codebook vectors included in a codebook, by considering a quantization error based on the channel vectors with respect to each of the data streams, and a selection codebook vector determining unit to determine selection codebook vectors corresponding to the plurality of data streams respectively from the at least two candidate codebook vectors, based on a signal-to-interference and noise ratio (SINR) of each of the data streams that is calculated according to each of the candidate codebook vectors.
摘要:
An ultra-low power super-regenerative receiver and method thereof are provided. The ultra-low power super-regenerative receiver includes a quench waveform generator configured to generate a quench waveform. The ultra-low power super-regenerative receiver further includes a super-regenerative oscillator configured to generate an oscillation signal based on the quench waveform. The ultra-low power super-regenerative receiver further includes a bandwidth adjustor configured to control the quench waveform based on a bandwidth of a signal received by the ultra-low power super-regenerative receiver, to dynamically adjust a bandwidth of the oscillation signal.