Random access method, radio communication terminal device, receiving method, and base station apparatus
Random access technology is provided for establishing an individual channel between a radio communication terminal device and a base station device in a short time and a radio communication terminal device executing the random access method. A RACH sub-channel allocation unit allocates a transmission packet input from a replication unit to an arbitrary sub-carrier at the RACH arbitrary time slot at random. An allocation unit judges whether an overlap is generated in the allocation result obtained by the RACH sub-channel allocation unit.
1. A terminal apparatus comprising:
a receiver configured to receive control information transmitted from a base station apparatus;
signal generating circuitry configured to generate, based on received information from the base station apparatus, a random access signal requesting service from the base station apparatus and including a number of duplicated random access sequences, where the number of duplicated random access sequences is based on the control information received in advance from the base station apparatus; and
a transmitter configured to transmit the random access signal, from the terminal apparatus to the base station apparatus over a random access channel, without waiting for a response from the base station apparatus to confirm whether any of the duplicated random access sequences has been received at the base station apparatus.
2. The terminal apparatus in claim 1 , wherein the control information indicates a number of terminal apparatuses belonging to a cell associated with the base station apparatus.
3. The terminal apparatus in claim 2 , wherein the signal generating circuitry is configured to determine the number of terminal apparatuses belonging to a cell from the control information.
4. The terminal apparatus in claim 2 , wherein as the number of terminal apparatuses belonging to the cell increases, the number of duplicated random access sequences decreases.
5. The terminal apparatus in claim 1 , wherein the duplicated random access sequences includes a random access sequence repeated successively in a time domain.
6. The terminal apparatus in claim 1 , wherein the transmitted random access signal includes one of the duplicated random access sequences in one time slot and another of the duplicated random access sequences in a second, different time slot.
7. The terminal apparatus in claim 1 , wherein the random access channel includes one or more of a time slot, frequency, or spreading code.
8. The terminal apparatus in claim 1 , wherein two of the duplicated random access sequences are consecutive in the time domain.
9. The terminal apparatus in claim 1 , wherein the transmitter is configured to transmit the random access signal on at least two consecutive time slots.
10. The terminal apparatus in claim 1 , wherein the number of duplicated random access sequences depends on a priority associated with the terminal apparatus.
11. A method implemented in a terminal comprising:
receiving control information transmitted from a base station apparatus;
generating, based on received information from the base station apparatus, a random access signal requesting service from the base station apparatus and including a number of duplicated random access sequences, where the number of duplicated random access sequences is based on the control information received in advance from the base station apparatus; and
transmitting the random access signal, from the terminal apparatus to the base station apparatus over a random access channel, without waiting for a response from the base station apparatus to confirm whether any of the duplicated random access sequences has been received at the base station apparatus.
12. The method in claim 11 , wherein the control information indicates a number of terminal apparatuses belonging to a cell associated with the base station apparatus.
13. The method in claim 12 , further comprising determining the number of terminals belonging to a cell from the control information.
14. The method in claim 12 , wherein as the number of terminals apparatuses belonging to the cell increases, the number of duplicated random access sequences decreases.
15. The method in claim 11 , wherein the duplicated random access sequences includes a random access sequence repeated successively in a time domain.
16. The method in claim 11 , wherein the transmitted random access signal includes one of the duplicated random access sequences in one time slot and another of the duplicated random access sequences in a second, different time slot.
17. The method in claim 11 , wherein the random access channel is associated with radio resources, the method further comprising transmitting the random access signal using a radio resource selected at random from radio resource candidates.
18. The method in claim 11 , wherein two of the duplicated random access sequences are consecutive in the time domain.
19. The method in claim 11 , further comprising transmitting the random access signal on at least two consecutive time slots.
20. The method in claim 11 , wherein the number of duplicated random access sequences also depends on a priority associated with the terminal apparatus.