Base station device, mobile station device, control information transmission method, control information reception method and program
In a radio system which allocates resources using as units resource blocks which are formed by frequency components and time components, control information for mobile station devices, and identification information which is used to identify a format for a control information transmission channel which transmits the control information is transmitted from the base station device to the mobile station devices by means of the control information transmission channel.
1. A mobile station device, comprising:
a receiver configured to receive control information from a base station device through a control information channel, the control information comprising a cyclic redundancy check (CRC) field and a payload field, and receive, from the base station device, information specifying a part of the payload field in which a control information item to be used by the mobile station device is placed; and
a processor configured to identify and decode the control information item from the control information based on a format of the payload field and the information specifying a part of the payload field;
wherein bits of the CRC field are masked by an identification information identifying the format of the payload field, the format specifying types of control information items included in the payload field, sizes of the control information items in bits, and positions of the control information items within the payload field.
2. The mobile station device according to claim 1 , wherein the control information includes at least one of downlink control information including a position of a physical resource block (PRB) where data addressed to the mobile station device is placed, modulation scheme, data length, and information required for hybrid automatic repeat request (HARQ).
3. The mobile station device according to claim 1 , wherein the control information includes at least one of uplink control information including a position of a physical resource block (PRB) to which the mobile station device transmit data, modulation scheme, data length, transmission timing control, power control, and a HARQ acknowledgement (ACK)/non-acknowledgement (NACK) for the data transmitted by the mobile station device.
4. A control information reception method, comprising:
receiving, by a mobile station device, control information from a base station device through a control information channel, the control information comprising a cyclic redundancy check (CRC) field and a payload field;
receiving, by the mobile station device, from the base station device, information specifying a part of the payload field in which a control information item to be used by the mobile station device is placed; and
identifying and decoding, by the mobile station device, the control information item from the control information based on a format of the payload field and the information specifying a part of the payload field;
wherein bits of the CRC field are masked by an identification information identifying the format of the payload field, the format specifying types of control information items included in the payload field, sizes of the control information items in bits, and positions of the control information items within the payload field.
5. The method according to claim 4 , wherein the control information includes at least one of downlink control information including a position of a physical resource block (PRB) where data addressed to the mobile station device is placed, modulation scheme, data length, and information required for hybrid automatic repeat request (HARQ).
6. The method according to claim 4 , wherein the control information includes at least one of uplink control information including a position of a physical resource block (PRB) to which the mobile station device transmit data, modulation scheme, data length, transmission timing control, power control, and a HARQ acknowledgement (ACK)/non-acknowledgement (NACK) for the data transmitted by the mobile station device.