Message transmission method and device
A message transmission method and device relating to the field of communications technologies are described that improve an anti-interference capability in message transmission. The method includes generating a scrambling code according to a scrambling code initialization seed, wherein the scrambling code initialization seed meets the following expression: c init =R·2 a 7 +P·( n f mod k +1)·2 b 7 and then scrambling a message according to the scrambling code. The method further includes sending the scrambled message to a terminal on a physical downlink shared channel. Because the first time parameter has different values at at least two different moments, scrambling codes determined at the at least two corresponding different moments are different. Therefore, a possibility at which the base station uses a same scrambling code to scramble a same system message repeatedly in a time period is reduced, so that an anti-interference capability in system message transmission is improved.
1. A message sending method, comprising:
generating a scrambling code according to a scrambling code initialization seed, wherein the scrambling code initialization seed meets the following expression:
c init =R· 2 a 7 +P ·( n f mod k +1)·2 b 7
where c init is the scrambling code initialization seed, R is a function of n RNTI , a 7 is a non-negative integer, P is a function of a cell identity, n f is the a frame number of a message, k is a prime number, and b 7 is a non-negative integer;
scrambling the message according to the scrambling code to render a scrambled message; and
sending the scrambled message to a terminal on a physical downlink shared channel,
wherein the message is a system message, a part of a system message, an encoded system message, or a part of an encoded system message, and
wherein the system message is a system information block.
2. The method according to claim 1 , wherein R is equal to the n RNTI , P is equal to N ID cell +1, where N ID cell is the cell identity, and k is equal to 61.
3. The method according to claim 1 , wherein a 7 is equal to a number of bits occupied by ( n f mod k +1)·P, where P is equal to N ID cell +1, N ID cell is the cell identity, and k is equal to 61.
4. The method according to claim 1 , wherein the frame number n f is a number of a radio frame in which a start position for sending the message is located.
5. The method according to claim 1 , wherein b 7 is equal to 0.
6. A message receiving method, the method comprising:
generating a scrambling code according to a scrambling code initialization seed, wherein the scrambling code initialization seed meets the following expression:
c init =R· 2 a 7 +P ·( n f mod k +1)·2 b 7
where c init is the scrambling code initialization seed, R is a function of n RNTI , a 7 is a non-negative integer, P is a function of a cell identity, n f is the a frame number of a message, k is a prime number, and b 7 is a non-negative integer;
receiving a scrambled message on a physical downlink shared channel; and
descrambling the scrambled message according to the scrambling code for acquiring the message,
wherein the message is a system message, a part of a system message, an encoded system message, or a part of an encoded system message, and
wherein the system message is a system information block.
7. The method according to claim 6 , wherein R is equal to the n RNTI , P is equal to N ID cell +1, where N ID cell is the cell identity, and k is equal to 61.
8. The method according to claim 6 , wherein a 7 is equal to a number of bits occupied by ( n f mod k +1)·P, where P is equal to N ID cell +1, N ID cell is the cell identity, and k is equal to 61.
9. The method according to claim 6 , wherein the frame number n f is a number of a radio frame in which a start position for sending the message is located.
10. The method according to claim 6 , wherein b 7 is equal to 0.
11. A network side device, comprising:
at least one processor, and
a non-transitory computer-readable medium storing computer-executable instructions that, when executed by the at least one processor, facilitate the network side device carrying out a method comprising:
generating a scrambling code according to a scrambling code initialization seed, wherein the scrambling code initialization seed meets the following expression:
c init =R· 2 a 7 +P ·( n f mod k +1)·2 b 7
where c init is the scrambling code initialization seed, R is a function of n RNTI , a 7 is a non-negative integer, P is a function of a cell identity, n f is the a frame number of a message, k is a prime number, and b 7 is a non-negative integer;
scrambling the message according to the scrambling code to render a scrambled message; and
sending the scrambled message to a terminal on a physical downlink shared channel,
wherein the message is a system message, a part of a system message, an encoded system message, or a part of an encoded system message, and
wherein the system message is a system information block.
12. The device according to claim 11 , where R is equal to the n RNTI , P is equal to N ID cell +1, where N ID cell is the cell identity, and k is equal to 61.
13. The device according to claim 11 , wherein a 7 is equal to a number of bits occupied by ( n f mod k +1)·P, where P is equal to N ID cell +1, N ID cell is the cell identity, and k is equal to 61.
14. The device according to claim 11 , wherein the frame number n f is a number of a radio frame in which a start position for sending the message is located.
15. The device according to claim 11 , wherein b 7 is equal to 0.
16. A communication device, comprising:
at least one processor, and
a non-transitory computer-readable medium storing computer-executable instructions that, when executed by the at least one processor, facilitate the communication device carrying out a method comprising:
generating a scrambling code according to a scrambling code initialization seed, wherein the scrambling code initialization seed meets the following expression:
c init =R· 2 a 7 +P ·( n f mod k +1)·2 b 7
where c init is the scrambling code initialization seed, R is a function of n RNTI , a 7 is a non-negative integer, P is a function of a cell identity, n f is the a frame number of a message, k is a prime number, and b 7 is a non-negative integer;
receiving a scrambled message on a physical downlink shared channel; and
descrambling the scrambled message according to the scrambling code for acquiring the message,
wherein the message is a system message, a part of a system message, an encoded system message, or a part of an encoded system message, and
wherein the system message is a system information block.
17. The device according to claim 16 , where R is equal to n RNTI , P is equal to N ID cell +1, where N ID cell is the cell identity, and k is equal to 61.
18. The device according to claim 16 , wherein a 7 is equal to a number of bits occupied by ( n f mod k +1)·P, where P is equal to N ID cell +1, N ID cell is the cell identity, and k is equal to 61.
19. The device according to claim 16 , wherein the frame number n f is a number of a radio frame in which a start position for sending the message is located.
20. The device according to claim 16 , wherein b 7 is equal to 0.