Satellite communication method and related communication device
Example satellite communication methods and example related devices are provided. One example satellite communication method includes generating a random access preamble sequence, where the random access preamble sequence includes a cyclic prefix, a sequence part, and a guard interval, the sequence part is obtained by performing frequency domain resource mapping and time-frequency transformation on a frequency domain sequence, and the frequency domain sequence is obtained based on a Zadoff-Chu (ZC) sequence and a mask sequence. The random access preamble sequence can then be output.
1 . A satellite communication method, comprising:
generating a random access preamble sequence, wherein the random access preamble sequence comprises a cyclic prefix, a sequence part, and a guard interval, wherein the sequence part is obtained by performing frequency domain resource mapping and time-frequency transformation on a frequency domain sequence, and the frequency domain sequence is obtained based on a Zadoff-Chu (ZC) sequence and a mask sequence; and
outputting the random access preamble sequence,
wherein in response to the mask sequence being a sequence common to a cell or satellite beam, generation of the mask sequence is related to at least one parameter of the cell or satellite beam, and the at least one parameter of the cell or satellite beam comprises at least one of an index number of the cell or satellite beam, an index number of a data subcarrier width, an index number of a synchronization signal block, or an index number of a bandwidth part,
wherein the sequence part comprises at least one subsequence A and at least one subsequence B, the subsequence A comprises at least one first preamble symbol, the subsequence B comprises at least one second preamble symbol, and the at least one first preamble symbol comprised in the subsequence A is different from the at least one second preamble symbol comprised in the subsequence B;
the subsequence A is obtained by performing frequency domain resource mapping and time-frequency transformation on a frequency domain sequence Za, and the frequency domain sequence Za is obtained based on the ZC sequence and the mask sequence; and
when the cyclic prefix comprises a first cyclic prefix and a second cyclic prefix:
the at least one subsequence A is located between the first cyclic prefix and the second cyclic prefix, and the at least one subsequence B is located between the second cyclic prefix and the guard interval;
the at least one subsequence B is located between the first cyclic prefix and the second cyclic prefix, and the at least one subsequence A is located between the second cyclic prefix and the guard interval; or
the at least one subsequence A and the at least one subsequence B alternately occur between the first cyclic prefix and the second cyclic prefix.
2 . The method according to claim 1 , wherein
x
u
,
v
(
n
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=
x
u
(
(
n
+
C
v
)
mod
N
z
c
)
x
u
(
i
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=
e
-
j
π
u
i
(
i
+
1
)
N
zc
,
0
≤
i
≤
N
zc
-
1
,
wherein
u is a root index of the ZC sequence, x u (i) represents one piece of data in an original ZC sequence, N zc is a length of the ZC sequence, x u,v (n) represents one piece of data in a ZC sequence on which cyclic shift processing is performed, and C v is a cyclic shift; and
y
~
u
,
v
(
n
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=
y
u
,
v
(
n
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·
c
(
n
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,
0
≤
n
≤
N
zc
-
1
y
u
,
v
(
n
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=
∑
m
=
0
N
ZC
-
1
x
u
,
v
(
m
)
·
e
-
j
2
π
m
n
N
Z
C
,
wherein
c(n) is an element in the mask sequence, and {tilde over (y)} u,v (n) represents one piece of data in the frequency domain sequence.
3 . The method according to claim 1 , wherein the mask sequence is an m sequence or a Gold sequence, and elements in the mask sequence are 1 and −1 or scaled values of 1 and −1.
4 . The method according to claim 1 , wherein in response to the mask sequence being a sequence common to an entire network, the mask sequence is a mask sequence of the random access preamble sequence and is agreed upon by all base stations and terminals, and all the base stations and terminals use a mask sequence comprising a same element; or
wherein in response to the mask sequence being a sequence related to a random access time-frequency resource, generation of the mask sequence is related to at least one parameter of the random access time-frequency resource, and the at least one parameter of the random access time-frequency resource comprises at least one of a start symbol, a start slot number, a frequency domain resource number, or an uplink carrier number of the random access time-frequency resource.
5 . The method according to claim 1 , wherein when lengths of all subsequences A are equal and lengths of all subsequences B are equal, an interval between any two adjacent subsequences B is at least greater than or equal to
⌈
N
CP
i
+
N
CP
f
⌉
,
⌈
•
⌉
represents rounding up,
N
CP
i
represents an integral quantity of preamble symbols comprised in the cyclic prefix, and
N
CP
f
represents a fractional quantity of preamble symbols comprised in the cyclic prefix.
6 . The method according to claim 1 , wherein a length of each subsequence A and a length of each subsequence B are separately greater than or equal to a length of the cyclic prefix.
7 . The method according to claim 6 , when the random access preamble sequence comprises one cyclic prefix:
the subsequence A and the subsequence B are located between the cyclic prefix and the guard interval, or
a time domain superimposed sequence of the subsequence A and the subsequence B is located between the cyclic prefix and the guard interval.
8 . A satellite communication apparatus, comprising:
at least one processor; and
at least one non-transitory memory coupled to the at least one processor and storing computer program instructions for execution by the at least one processor to:
generate a random access preamble sequence, wherein the random access preamble sequence comprises a cyclic prefix, a sequence part, and a guard interval, the sequence part is obtained by performing frequency domain resource mapping and time-frequency transformation on a frequency domain sequence, and the frequency domain sequence is obtained based on a Zadoff-Chu (ZC) sequence and a mask sequence; and
output the random access preamble sequence,
wherein in response to the mask sequence being a sequence common to a cell or satellite beam, generation of the mask sequence is related to at least one parameter of the cell or satellite beam, and the at least one parameter of the cell or satellite beam comprises at least one of an index number of the cell or satellite beam, an index number of a data subcarrier width, an index number of a synchronization signal block, or an index number of a bandwidth part,
wherein the sequence part comprises at least one subsequence A and at least one subsequence B, the subsequence A comprises at least one first preamble symbol, the subsequence B comprises at least one second preamble symbol, and the at least one first preamble symbol comprised in the subsequence A is different from the at least one second preamble symbol comprised in the subsequence B;
the subsequence A is obtained by performing frequency domain resource mapping and time-frequency transformation on a frequency domain sequence Za, and the frequency domain sequence Za is obtained based on the ZC sequence and the mask sequence; and
when the cyclic prefix comprises a first cyclic prefix and a second cyclic prefix:
the at least one subsequence A is located between the first cyclic prefix and the second cyclic prefix, and the at least one subsequence B is located between the second cyclic prefix and the guard interval;
the at least one subsequence B is located between the first cyclic prefix and the second cyclic prefix, and the at least one subsequence A is located between the second cyclic prefix and the guard interval; or
the at least one subsequence A and the at least one subsequence B alternately occur between the first cyclic prefix and the second cyclic prefix.
9 . The apparatus according to claim 8 , wherein
x
u
,
v
(
n
)
=
x
u
(
(
n
+
C
v
)
mod
N
z
c
)
x
u
(
i
)
=
e
-
j
π
u
i
(
i
+
1
)
N
zc
,
0
≤
i
≤
N
zc
-
1
,
wherein
u is a root index of the ZC sequence, x u (i) represents one piece of data in an original ZC sequence, N zc is a length of the ZC sequence, x u,v (n) represents one piece of data in a ZC sequence on which cyclic shift processing is performed, and C v is a cyclic shift; and
y
~
u
,
v
(
n
)
=
y
u
,
v
(
n
)
·
c
(
n
)
,
0
≤
n
≤
N
zc
-
1
y
u
,
v
(
n
)
=
∑
m
=
0
N
ZC
-
1
x
u
,
v
(
m
)
·
e
-
j
2
π
m
n
N
Z
C
,
wherein
c(n) Is an element in the mask sequence, and {tilde over (y)} u,v (n) represents one piece of data in the frequency domain sequence.
10 . The apparatus according to claim 8 , wherein the mask sequence is an m sequence or a Gold sequence, and elements in the mask sequence are 1 and −1 or scaled values of 1 and −1.
11 . The apparatus according to claim 8 , wherein in response to the mask sequence being a sequence common to an entire network, the mask sequence is a mask sequence of the random access preamble sequence and is agreed upon by all base stations and terminals, and all the base stations and terminals use a mask sequence comprising a same element; or
wherein in response to the mask sequence being a sequence related to a random access time-frequency resource, generation of the mask sequence is related to at least one parameter of the random access time-frequency resource, and the at least one parameter of the random access time-frequency resource comprises at least one of a start symbol, a start slot number, a frequency domain resource number, or an uplink carrier number of the random access time-frequency resource.
12 . The apparatus according to claim 8 , wherein when lengths of all subsequences A are equal and lengths of all subsequences B are equal, an interval between any two adjacent subsequences B is at least greater than or equal to
⌈
N
CP
i
+
N
CP
f
⌉
,
⌈
•
⌉
represents rounding up,
N
CP
i
represents an integral quantity of preamble symbols comprised in the cyclic prefix, and
N
CP
f
represents a fractional quantity of preamble symbols comprised in the cyclic prefix.
13 . The apparatus according to claim 8 , wherein a length of each subsequence A and a length of each subsequence B are separately greater than or equal to a length of the cyclic prefix.
14 . The apparatus according to claim 13 , when the random access preamble sequence comprises one cyclic prefix:
the subsequence A and the subsequence B are located between the cyclic prefix and the guard interval, or
a time domain superimposed sequence of the subsequence A and the subsequence B is located between the cyclic prefix and the guard interval.
15 . The method according to claim 1 , wherein the subsequence A comprises at least two consecutively placed preamble symbols.
16 . The method according to claim 1 , wherein the subsequence B is obtained by using a same ZC sequence as the subsequence A and a different mask sequence from the subsequence A; or the subsequence B is obtained by using a different ZC sequence from the subsequence A; or the subsequence B is directly filled with the ZC sequence, filled with a pseudorandom number, or set to be zero.
17 . The apparatus according to claim 8 , wherein the subsequence A comprises at least two consecutively placed preamble symbols.
18 . The apparatus according to claim 8 , wherein the subsequence B is obtained by using a same ZC sequence as the subsequence A and a different mask sequence from the subsequence A; or the subsequence B is obtained by using a different ZC sequence from the subsequence A; or the subsequence B is directly filled with the ZC sequence, filled with a pseudorandom number, or set to be zero.