Abstract: A wireless communication with modulation and demodulation set based on channel information is disclosed. An operating method of a first wireless communication device includes: transmitting a pilot signal via a wireless channel to a second wireless communication device; receiving channel state information, estimated by and transmitted from the second wireless communication device in response to the pilot signal, the channel state information including amplitude information and phase information of a wireless channel; setting a modulation method for data transmission based on the amplitude information and the phase information of the wireless channel; generating modulated data based on the modulation method; and transmitting the modulated data via the wireless channel.

Abstract: A wireless communication with modulation and demodulation set based on channel information is disclosed. An operating method of a first wireless communication device includes: transmitting a pilot signal via a wireless channel to a second wireless communication device; receiving channel state information, estimated by and transmitted from the second wireless communication device in response to the pilot signal, the channel state information including amplitude information and phase information of a wireless channel; setting a modulation method for data transmission based on the amplitude information and the phase information of the wireless channel; generating modulated data based on the modulation method; and transmitting the modulated data via the wireless channel.

Abstract: A communication device performing device-to-device (D2D) communication and an operating method of the communication device are provided. The operating method of the communication device includes receiving a first message, the first message including resources of a direct link for device-to-device (D2D) communication from a base station, receiving a second message, the second message including first information from a counterpart terminal of the D2D communication, the first information related to channel information of a downlink of cellular communication and channel information of the direct link, and selecting one of the cellular communication or the D2D communication as a communication mode with the counterpart terminal, based on channel information of an uplink of the cellular communication and the received first information.

Abstract: A method of a Mobile Station (MS) for discovering neighbor MSs in a Device to Device (D2D) network includes broadcasting, by a discovery MS, a discovery request signal for discovering neighbor MSs, using a discovery request resource region repeated with a first period, if a neighbor MS discovery event is detected; and receiving, by the discovery MS, a discovery signal from at least one of other MSs in response to the discovery request signal, using a discovery resource region repeated with a second period. Other embodiments including a method for a central node discovering neighbor MSs and a discovery MS and a central node are also disclosed.

Abstract: A method of a Mobile Station (MS) for discovering neighbor MSs in a Device to Device (D2D) network includes broadcasting, by a discovery MS, a discovery request signal for discovering neighbor MSs, using a discovery request resource region repeated with a first period, if a neighbor MS discovery event is detected; and receiving, by the discovery MS, a discovery signal from at least one of other MSs in response to the discovery request signal, using a discovery resource region repeated with a second period. Other embodiments including a method for a central node discovering neighbor MSs and a discovery MS and a central node are also disclosed.