Communication system, communication terminal and base station

Abstract

Provided is a communication system capable of suppressing decrease in a transmission rate. An eNB communicates with a UE using a self-contained subframe. The self-contained subframe includes a downlink signal to be transmitted from the eNB to the UE, and an uplink signal to be transmitted from the UE to the eNB in response to the downlink signal. The uplink signal has a structure including an uplink control signal indicating information for controlling transmission of the uplink signal, and uplink user data to be transmitted before and after the uplink control signal. The eNB notifies the UE of a structure of the uplink signal. The eNB may predetermine scheduling for retransmission to retransmit the downlink signal, before performing initial transmission of the downlink signal.

1 . (canceled) 
     
     
         2 . A communication system comprising:
 a base station; and   a communication terminal configured to communicate via radio communication with the base station,   wherein the communication terminal transmits an uplink control signal by frequency-division multiplexing the uplink control signal with an uplink sounding reference signal in a same symbol, the uplink control signal being a control signal for an uplink signal that is transmitted from the communication teminal to the base station, and   the base station receives the uplink control signal and the uplink sounding reference signal in the same symbol.   
     
     
         3 . The communication system according to  claim 2 , wherein the communication terminal frequency-division multiplexes the uplink control signal with the uplink sounding reference signal that is transmitted from the communication terminal. 
     
     
         4 . The communication system according to  claim 2 , wherein the communication terminal frequency-division multiplexes the uplink control signal with the uplink sounding reference signal that is transmitted from another communication terminal different from the communication terminal. 
     
     
         5 . A communication terminal configured to communicate via radio communication with a base station,
 wherein the communication terminal transmits an uplink control signal by frequency-division multiplexing the uplink control signal with an uplink sounding reference signal in a same symbol, the uplink control signal being a control signal for an uplink signal that is transmitted from the communication terminal to the base station.   
     
     
         6 . A base station configured to communicate via radio communication with a communication terminal,
 wherein an uplink control signal is frequency-division multiplexed with an uplink sounding reference signal in a same symbol; the uplink control signal being a control signal for an uplink signal that is transmitted from the communication terminal to the base station, and   the base station receives the uplink control signal and the uplink sounding reference signal in the same symbol.