User equipment and random access method
User equipment communicating with a base station of a wireless communication system including the base station and the user equipment includes a selection unit configured to select a random access signal group from a plurality of random access signal groups by comparing a size of a message transmitted through a predetermined logical channel with a predetermined threshold value and select a random access signal from the random access signal group; and a transmission unit configured to transmit the random access signal selected by the selection unit to the base station, wherein the transmission unit transmits the message through the predetermined logical channel using a resource allocated according to a response from the base station with respect to the random access signal.
1. A user equipment communicating with a base station of a wireless communication system including the base station and the user equipment, the user equipment comprising:
a processor that:
selects a random access signal group from a plurality of random access signal groups by comparing, with a predetermined threshold value, a size of a Common Control Channel Service Data Unit (CCCH SDU) added with a MAC header, the CCCH SDU being a Radio Resource Control connection resume message for resuming a Radio Resource Control connection transmitted via a common control channel; and
selects a random access signal from the random access signal group; and
a transmitter that transmits the random access signal selected by the processor to the base station,
wherein the transmitter transmits the CCCH SDU through the common control channel using a resource allocated by a response from the base station with respect to the random access signal.
2. The user equipment according to claim 1 , wherein, upon detecting that the size of the CCCH SDU added with the MAC header is greater than the predetermined threshold value, the processor selects a random access signal group corresponding to a case where the size is greater than the predetermined threshold value from the two random access signal groups.
3. The user equipment according to claim 1 , wherein, upon detecting that the size of the CCCH SDU added with the MAC header is equal to the predetermined threshold value, the processor selects a random access signal group corresponding to the predetermined threshold value from the plurality of random access signal groups.
4. The user equipment according to claim 3 , wherein, upon detecting that the size of the CCCH SDU added with the MAC header is greater than the predetermined threshold value and a path loss is smaller than a predetermined value, the processor selects, from the plurality of random access signal groups, a predetermined random access signal group different from the random access signal group corresponding to the predetermined threshold value.
5. The user equipment according to claim 1 ,
wherein the processor
determines whether a first condition is satisfied, the first condition being such that the size of the CCCH SDU added with the MAC header is greater than the predetermined threshold value and a path loss is smaller than a predetermined, and
determines whether a second condition is satisfied, the second condition being such that the size of the CCCH SDU added with the MAC header is equal to the predetermined threshold value in response to detecting that the first condition is not satisfied, and selects a random access signal group corresponding to the predetermined threshold value in response to detecting that the second condition is satisfied.
6. The user equipment according to claim 5 ,
wherein, upon detecting that the second condition is not satisfied, the processor determines whether or not a third condition is satisfied, the third condition being such that the size of the CCCH SDU added with the MAC header is smaller than the predetermined threshold value, the size of the CCCH SDU added with the MAC header is larger than a predetermined second threshold value, and a path loss is smaller than a predetermined value, and
wherein the processor selects a random access signal group corresponding to a size between the predetermined second threshold value and the predetermined threshold value in response to detecting that the third condition is satisfied, and the processor selects a random access signal group corresponding to the predetermined second threshold value in response to detecting that the third condition is not satisfied.
7. A random access method executed by user equipment communicating with a base station of a wireless communication system including the base station and the user equipment, the random access method comprising:
selecting a random access signal group from a plurality of random access signal groups by comparing, with a predetermined threshold value, a size of a Common Control Channel Service Data Unit (CCCH SDU) added with a MAC header, the CCCH SDU being a Radio Resource Control connection resume message for resuming a Radio Resource Control connection transmitted via a common control channel, and selecting a random access signal from the random access signal group;
transmitting the selected random access signal to the base station; and
transmitting the CCCH SDU through the common control channel by using a resource allocated according to a response from the base station with respect to the random access signal.