Communication method and apparatus for communication of a control channel and data channel
This application provides a communication method and apparatus used for the internet of vehicles, for example, vehicle to everything (V2X), Long Term Evolution-Vehicle (LTE-V), and vehicle-to-vehicle communication (V2V). The method includes: a first terminal apparatus generates, based on indication information such as an aggregation level of a control channel or a demodulation reference sequence configuration of a data channel, a demodulation reference sequence of another control channel, and sends the demodulation reference sequence to a second terminal apparatus. The second terminal apparatus can obtain the indication information in a process of detecting the demodulation reference sequence of the other control channel, to demodulate the control channel or the data channel.
1. A communication method, comprising:
generating, by a first terminal apparatus, a first demodulation reference sequence based on an aggregation level of a second control channel, wherein the first demodulation reference sequence is for demodulating a first control channel, wherein a first demodulation reference signal generated based on the first demodulation reference sequence is mapped to the first control channel, and wherein first control information carried on the first control channel and second control information carried on the second control channel are for demodulating a data channel; and
sending, by the first terminal apparatus, the first control channel, the second control channel, and the data channel to a second terminal apparatus in a first slot.
2. The communication method according to claim 1 , wherein generating the first demodulation reference sequence based on aggregation level of the second control channel comprises:
determining, by the first terminal apparatus, an initial value of the first demodulation reference sequence based on the aggregation level of the second control channel; and
generating, by the first terminal apparatus, the first demodulation reference sequence based on the initial value of the first demodulation reference sequence.
3. The communication method according to claim 2 , wherein determining the initial value of the first demodulation reference sequence based on the aggregation level of the second control channel comprises:
determining, by the first terminal apparatus, a quantity of symbols of the first slot, a slot number of the first slot, and a symbol number of a symbol that carries the first demodulation reference sequence and that is in the first slot.
4. The communication method according to claim 3 , wherein determining the quantity of symbols of the first slot, the slot number of the first slot, and the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot comprises:
determining, by the first terminal apparatus, that the initial value of the first demodulation reference sequence satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ k )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m is the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, k is the aggregation level of the second control channel, and an operator mod represents a modulo operation.
5. The communication method according to claim 3 , wherein determining the quantity of symbols of the first slot, the slot number of the first slot, and the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot comprises:
determining, by the first terminal apparatus, that the initial value of the first demodulation reference sequence satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ i )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, i is an index value of the aggregation level of the second control channel, and an operator mod represents a modulo operation.
6. A communication method, comprising:
receiving, by a second terminal apparatus, a first control channel from a first terminal apparatus in a first slot, wherein the first control channel carries a first demodulation reference signal and first control information, and wherein a first demodulation reference sequence for generating the first demodulation reference signal is for demodulating the first control channel;
determining, by the second terminal apparatus, an aggregation level of a second control channel based on the first demodulation reference sequence;
receiving, by the second terminal apparatus, the second control channel from the first terminal apparatus in the first slot based on the aggregation level of the second control channel, wherein the first control information carried on the first control channel and second control information carried on the second control channel are for demodulating a data channel; and
receiving, by the second terminal apparatus, the data channel from the first terminal apparatus in the first slot based on the first control information and the second control information.
7. The communication method according to claim 6 , wherein determining the aggregation level of the second control channel based on the first demodulation reference sequence comprises:
determining, by the second terminal apparatus, an initial value of the first demodulation reference sequence; and
determining, by the second terminal apparatus, the aggregation level of the second control channel based on the initial value of the first demodulation reference sequence.
8. The communication method according to claim 7 , wherein determining the aggregation level of the second control channel based on the initial value of the first demodulation reference sequence comprises:
determining, by the second terminal apparatus, a quantity of symbols of the first slot, a slot number of the first slot, and a symbol number of a symbol that carries the first demodulation reference sequence and that is in the first slot.
9. The communication method according to claim 8 , wherein determining the quantity of symbols of the first slot, the slot number of the first slot, and the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot comprises:
determining, by the second terminal apparatus, that the aggregation level of the second control channel satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ k )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f ms the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, k is the aggregation level of the second control channel, and an operator mod represents a modulo operation.
10. The communication method according to claim 8 , wherein determining the quantity of symbols of the first slot, the slot number of the first slot, and the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot comprises:
determining, by the second terminal apparatus, that an index value of the aggregation level of the second control channel satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ i )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f ms the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, i is the index value of the aggregation level of the second control channel, and an operator mod represents a modulo operation.
11. A communication apparatus, comprising:
a memory storage comprising instructions; and
one or more processors in communication with the memory storage, wherein the execution of the instructions by the one or more processors causes the apparatus to:
generate a first demodulation reference sequence based on an aggregation level of a second control channel, wherein the first demodulation reference sequence is for demodulating a first control channel, wherein a first demodulation reference signal generated based on the first demodulation reference sequence is mapped to the first control channel, and wherein first control information carried on the first control channel and second control information carried on the second control channel are for demodulating a data channel; and
send the first control channel, the second control channel, and the data channel to a second terminal apparatus in a first slot.
12. The communication apparatus according to claim 11 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine an initial value of the first demodulation reference sequence based on the aggregation level of the second control channel; and
generate the first demodulation reference sequence based on the initial value of the first demodulation reference sequence.
13. The communication apparatus according to claim 12 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine a quantity of symbols of the first slot, a slot number of the first slot, and a symbol number of a symbol that carries the first demodulation reference sequence and that is in the first slot.
14. The communication apparatus according to claim 13 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine that the initial value of the first demodulation reference sequence satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ k )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, k is the aggregation level of the second control channel, and an operator mod represents a modulo operation.
15. The communication apparatus according to claim 13 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine that the initial value of the first demodulation reference sequence satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ i )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, i is an index value of the aggregation level of the second control channel, and an operator mod represents a modulo operation.
16. A communication apparatus, comprising:
a memory storage comprising instructions; and
one or more processors in communication with the memory storage, wherein execution of the instructions by the one or more processors causes the apparatus to:
receive a first control channel from a first terminal apparatus in a first slot, wherein the first control channel carries a first demodulation reference signal and first control information, and wherein a first demodulation reference sequence for generating the first demodulation reference signal is for demodulating the first control channel;
determine an aggregation level of a second control channel based on the first demodulation reference sequence;
receive the second control channel from the first terminal apparatus in the first slot based on the aggregation level of the second control channel, wherein the first control information carried on the first control channel and second control information carried on the second control channel are for demodulating a data channel; and
receive the data channel from the first terminal apparatus in the first slot based on the first control information and the second control information.
17. The communication apparatus according to claim 16 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine an initial value of the first demodulation reference sequence; and
determine the aggregation level of the second control channel based on the initial value of the first demodulation reference sequence.
18. The communication apparatus according to claim 17 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine a quantity of symbols of the first slot, a slot number of the first slot, and a symbol number of a symbol that carries the first demodulation reference sequence and that is in the first slot.
19. The communication apparatus according to claim 17 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine that the aggregation level of the second control channel satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ k )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m is the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, k is the aggregation level of the second control channel, and an operator mod represents a modulo operation.
20. The communication apparatus according to claim 17 , wherein the execution of the instructions by the one or more processors further causes the apparatus to:
determine that an index value of the aggregation level of the second control channel satisfies:
c init =(2 17 ( N symb slot n s,f m +l+ 1)+ i )mod(2 31 ),
wherein c init is the initial value of the first demodulation reference sequence, N symb slot is the quantity of symbols of the first slot, n s,f m is the slot number of the first slot, l is the symbol number of the symbol that carries the first demodulation reference sequence and that is in the first slot, i is the index value of the aggregation level of the second control channel, and an operator mod represents a modulo operation.