摘要:
A selective cooperative relaying method, the method including: determining, by a base station, whether a mobile station for which the base station provides a service is the mobile station necessary for direct transmission or is the mobile station necessary for cooperative relaying via a relay station; and selecting, by a base station, mobile stations using a simple relaying scheme, a cooperative transmission diversity scheme, or a cooperative receiving diversity scheme from mobile stations necessary for the cooperative relaying via the relay station.
摘要:
A selective cooperative relaying method, the method including: determining, by a base station, whether a mobile station for which the base station provides a service is the mobile station necessary for direct transmission or is the mobile station necessary for cooperative relaying via a relay station; and selecting, by a base station, mobile stations using a simple relaying scheme, a cooperative transmission diversity scheme, or a cooperative receiving diversity scheme from mobile stations necessary for the cooperative relaying via the relay station.
摘要:
Disclosed is an apparatus and method for cooperative reception diversity based on signal point rearrangement or superposition modulation in a relay system, the method includes receiving a superposition-modulated symbol from a transmitting unit, demodulating the received symbol and decoding the demodulated symbol, modulating the received symbol using superposition modulation different from the superposition modulation used in the transmitting unit, and then relaying the modulated symbol to a reception unit, calculating an LLR of the symbol when a certain superposition-modulated symbol is received from a transmitting unit, calculating an LLR of a symbol modulated using superposition modulation different from the superposition modulation used in the transmitting unit when the symbol modulated using the different superposition modulation is received from a relay station, and summing and combining an LLR of each symbol received through the transmitting unit and relay station.
摘要:
A method and apparatus for method for providing cooperative reception diversity based on signal point rearrangement and superposition modulation performed at a relay station is discussed. A first technique performs superposition modulation at a relay station and a second technique employs signal point rearrangement at a relay station. The superposition modulation is a different type of superposition modulation than that employed by the transmitter of the signal. Similarly, the signal point rearrangement is a different type of signal point rearrangement than that employed by the transmitter of the signal. As a result of the superposition modulation or signal point rearrangement performed by the relay station, the reliability of a signal received by a reception unit at the destination receiver is improved.
摘要:
A relay method of a wireless communication system according to one embodiment of the present invention relates to a relay method of a wireless communication system in which at least one relay device communicates with a base station. The relay method comprises the steps of: each relay device setting information about a frequency band to be relayed, composing a control signal including the information about the set frequency band, and transmitting the control signal to at least one relay device; and receiving the control signal, extracting the information about the frequency band included in the control signal, amplifying the signal according to the information about the frequency band set in each relay device, and transmitting the amplified signal to at least one terminal.
摘要:
The present invention provides a method of bandpass sampling which particularly includes the single-sideband signal conversion procedure prior to the sampling process in the purpose of lowering the required sampling frequency. Conversion of the bandpass RF signal into a single-sideband spectrum signal which has the spectrum components only in either the positive or the negative frequency domain is accomplished by bandpass-filtering, or more effectively by using a Hilbert transformer. This invention includes a method of finding the minimum sampling frequency for simultaneous frequency down-conversion of multiple RF bandpass signals. It is expected from this invention that the components additionally required in the RF receiver due to the proposed bandpass sampling method is the bandpass filters or the Hilbert transformer for single-sideband conversion, but the benefits from this invention could be the reduced ADC speed performance and the subsequent digital processing load in the receiver system because of the reduced data rates.
摘要:
A device for generating a transmission codebook in a communication system including a multi-input multi-output (MIMO) antenna according to an embodiment of the present invention includes: a frequency determiner that determines a frequency to allow the transmission codebook to have an optimal characteristic; a precoding matrix generator that generates a precoding matrix on the basis of the frequency; and a codebook generator that generates a retransmission codebook to be used for retransmission on the basis of the precoding matrix and generates the transmission codebook on the basis of the retransmission codebook.
摘要:
In a symbol mapping method, transmission data is encoded to output information bits and redundancy bits. The information bits and the redundancy bits are mapped to a symbol according to a first mapping scheme at a first transmission, and the information bits and the redundancy bits are mapped to a symbol according to a second mapping scheme at a second transmission.
摘要:
A method and apparatus for allocating a radio resource in a wireless sensor network are provided, in which a signal requesting a radio resource allocation is received from any one of sensors included in the wireless sensor network, an amount of remaining energy is compared with respect to each zone where a sensor transmitting the signal is included, an order of zones, from a zone comprising a greatest amount of remaining energy to a zone having a least amount of remaining energy, is determined as a result of the comparison, and a time slot is allocated to a sensor of each zone according to the determined order of zones, when transmitting a frame for the radio resource allocation.
摘要:
A method and system for efficiently transmitting data, to which scalable image coding has been applied over a single frequency network is provided. The system includes a control server which re-packetizes data packets, received from a multimedia server, into a scalable bit stream by separately encoding the data packets into a base layer and one or more enhancement layers, and at least one base station which adaptively multicasts and broadcasts the scalable bit stream, received from the control server, to a plurality of terminals located in the area of a cell. The at least one base station multicasts and broadcasts the base layer across the area of the cell, and adaptively transmits the one or more enhancement layers depending on channel status or terminal performance of the plurality of terminals.