Transmission device, reception device, transmission method, and reception method
The purpose of the invention is to realize appropriate random-access procedures in accordance with propagation delay between a terminal and a base station. A terminal ( 100 ) comprises a wireless transmission unit ( 104 ) that transmits signals of a random-access channel, and a control unit ( 108 ) that controls resource settings regarding transmission of signals on the random-access channel on the basis of effectiveness of information relating to adjustment of transmission timing.
1. A transmission apparatus, comprising:
transmission circuitry, which, in operation, transmits a signal of a random access channel; and
control circuitry, which, in operation, controls a resource configuration relevant to transmission of the signal in the random access channel based on a validity property of information on adjustment of a transmission timing, wherein
the control circuitry, in operation, supports first and second random access procedures,
when the information on the adjustment of the transmission timing is invalid, the control circuitry uses a first resource configuration in the random access channel or uses a second resource configuration in the random access channel, and
when the information on the adjustment of the transmission timing is valid, the control circuitry controls the first random access procedure or the second random access procedure, the second random access procedure having a larger number of steps than the first random access procedure.
2. The transmission apparatus according to claim 1 , wherein,
in the first resource configuration, at least one of a length of a cyclic prefix, a length of a guard period, or a length of a preamble sequence of the signal of the random access channel is longer than that in the second resource configuration.
3. The transmission apparatus according to claim 2 , wherein,
when the length of the preamble sequence in the first resource configuration is longer than that in the second resource configuration, a length of a code sequence used for the preamble sequence in the first resource configuration is longer than that in the second resource configuration, and/or a number of repetitions of the code sequence of the preamble sequence in the first resource configuration is greater than that in the second resource configuration.
4. The transmission apparatus according to claim 1 , wherein
a transmission occasion for the signal in the first resource configuration differs from a transmission occasion for the signal in the second resource configuration in at least one of time and frequency.
5. The transmission apparatus according to claim 1 , wherein
a transmission occasion for the signal in the first resource configuration is less frequent than a transmission occasion for the signal in the second resource configuration.
6. The transmission apparatus according to claim 1 , wherein
a number of code sequences usable for the first resource configuration is smaller than a number of code sequences usable for the second resource configuration.
7. The transmission apparatus according to claim 1 , wherein
the control circuitry controls transmission of the signal in the first resource configuration when a response to the signal having been transmitted in the second resource configuration is not received.
8. The transmission apparatus according to claim 1 , wherein
the control circuitry applies the first resource configuration to the signal of the random access channel that is to be transmitted in the first random access procedure.
9. A reception apparatus, comprising:
reception circuitry, which, in operation, receives a signal of a random access channel; and
control circuitry, which, in operation, controls reception of the signal based on a resource configuration relevant to transmission of the signal in the random access channel, the resource configuration being associated with a validity property of information on adjustment of a transmission timing, wherein
the control circuitry, in operation, supports first and second random access procedures,
when the information on the adjustment of the transmission timing is invalid, the control circuitry uses a first resource configuration in the random access channel or a second resource configuration in the random access channel, and
when the information on the adjustment of the transmission timing is valid, the control circuitry controls the first random access procedure or the second random access procedure, the second random access procedure having a larger number of steps than the first random access procedure.
10. The reception apparatus according to claim 9 , comprising:
transmission circuitry, which, in operation, transmits information indicating whether to use a first resource configuration associated with invalidity of the information on the adjustment of the transmission timing or to use a second resource configuration associated with validity of the information on the adjustment of the transmission timing.
11. A transmission method, comprising:
controlling a resource configuration relevant to transmission of a signal in a random access channel based on a validity property of information on adjustment of a transmission timing; and
transmitting the signal of the random access channel, wherein
when the information on the adjustment of the transmission timing is invalid, the controlling uses a first resource configuration in the random access channel or a second resource configuration in the random access channel, and
when the information on the adjustment of the transmission timing is valid, the controlling includes selecting between a first random access procedure or a second random access procedure, the second random access procedure having a larger number of steps than the first random access procedure.
12. A reception method, comprising:
controlling reception of a signal based on a resource configuration relevant to transmission of the signal in a random access channel, the resource configuration being associated with a validity property of information on adjustment of a transmission timing; and
receiving the signal of the random access channel, wherein
when the information on the adjustment of the transmission timing is invalid, the controlling uses a first resource configuration in the random access channel or a second resource configuration in the random access channel, and
when the information on the adjustment of the transmission timing is valid, the controlling includes selecting between a first random access procedure or a second random access procedure, the second random access procedure having a larger number of steps than the first random access procedure.