Radio communication system, base station device and mobile station device utilizing an intermittent reception

A radio communication system comprising:

• a base station device;
• and
• a mobile station device,
• the base station device configured to:
• communicate with the mobile station using a plurality of time slots of a frame, each slot being able to include at least a first part for a downlink control channel and a second part for a downlink shared data channel,
• variably set a periodic period during which the mobile station device is to be enabled to receive, in the first part in each slot, the downlink control channel containing radio resources scheduling information on radio resources for a downlink data channel in the same time slot in which the control channel is placed,
• variably set an interval between the start of the period and the start of a next period, and
• transmit the period and the interval together in a single RRC message to the mobile station device, and
• the mobile station device including a radio portion that receives the RRC message and a DRX control portion that sets the interval and the period of execution of a reception process on the downlink control channel containing radio resources scheduling information, based on the RRC message.