Sequence allocating method and sequence allocating apparatus
View Patent ↗A sequence allocating method and apparatus wherein in a system where a plurality of different Zadoff-Chu sequences or GCL sequences are allocated to a single cell, the arithmetic amount and circuit scale of a correlating circuit at a receiving end can be reduced. In ST 201 , a counter (a) and a number (p) of current sequence allocations are initialized, and in ST 202 , it is determined whether the number (p) of current sequence allocations is coincident with a number (K) of allocations to one cell. In ST 203 , it is determined whether the number (K) of allocations to the one cell is odd or even. If K is even, in ST 204 -ST 206 , sequence numbers (r=a and r=N−a), which are not currently allocated, are combined and then allocated. If K is odd, in ST 207 -ST 212 , for sequences that cannot be paired, one of sequence numbers (r=a and r=N−a), which are not currently allocated, is allocated.
1. A base station comprising:
a transmitter that broadcasts information related to a set of sequences configured to be available in a cell for use by a mobile station; and
a receiver that receives a sequence which is random-access-preamble-transmitted from the mobile station, the sequence being one of the set of sequences available in the cell;
wherein the set of sequences available in the cell includes a sequence of r=a and a sequence of r=N−a, where r is a sequence number, a is an integer, and N is a sequence length, and the sequences are defined by the following equation or an equation cyclic shifted from the following equation:
c
r
(
k
)
=
exp
{
-
j
2
π
r
N
(
k
(
k
+
1
)
2
+
qk
)
}
where k=0, 1, 2, . . . N−1, and q is an integer, and
the sequence of r=a and the sequence of r=N−a are conjugate to each other.
2. The base station according to claim 1 , wherein the set of sequences available in the cell further includes a sequence of r=a′ (a′≠a) and a sequence of r=N−a′.
3. The base station according to claim 1 , wherein the N is a prime number.
4. The base station according to claim 1 , wherein the set of sequences available in the cell is configured by a network that controls the base station.
5. The base station according to claim 1 , wherein a number of the sequences configured to be included in the set of sequences available in the cell is less than the N.
6. The base station according to claim 1 , wherein the information broadcasted from the base station includes an index indicative of the set of sequences available in the cell.
7. A communication method comprising:
broadcasting information related to a set of sequences configured to be available in a cell for use by a mobile station; and
receiving a sequence which is random-access-preamble-transmitted from the mobile station, the sequence being one of the set of sequences available in the cell;
wherein the set of sequences available in the cell included a sequence of r=a and a sequence of r=N−a, where r is a sequence number, a is an integer, and N is a sequence length, and the sequences are defined by the following equation or an equation cyclic shifted from the following equation:
c
r
(
k
)
=
exp
{
-
j
2
π
r
N
(
k
(
k
+
1
)
2
+
qk
)
}
where k=0, 1, 2, . . . N−1, and q is an integer, and
the sequence of r=a and the sequence of r=N−a are conjugate to each other.
8. The communication method according to claim 7 , wherein the set of sequences available in the cell further includes a sequence of r=a′ (a′≠a) and a sequence of r=N−a′.
9. The communication method according to claim 7 , wherein the N is a prime number.
10. The communication method according to claim 7 , wherein the set of sequences available in the cell is configured by a network.
11. The communication method according to claim 7 , wherein a number of the sequences configured to be included in the set of sequences available in the cell is less than the N.
12. The communication method according to claim 7 , wherein the information broadcasted includes an index indicative of the set of sequences available in the cell.