Data transmission method and apparatus
The present invention provides a data transmission method and apparatus. The method includes: transmitting physical downlink channel data according to a first-type reference signal (RS) or a second-type RS or a third-type RS. The method of the present invention ensures a balance between data transmission performance and RS overheads for different NarrowBand-Internet Of Things (NB-IOT) physical downlink channel data, thereby resolving the problem in the related art of not knowing which RS is to be used to transmit NB-IOT physical channel data.
1. A method performed by a wireless communication node, comprising:
determining a third-type reference signal (RS) based on a signaling indication,
wherein a third pattern of the third-type RS comprises a superposition of a first pattern of a first-type RS and a second pattern of a second-type RS, wherein the first pattern is a pattern for an RS of K1 ports and does not overlap with a pattern of a cell-specific reference signal (CRS) in Long Term Evolution (LTE) system and the second pattern is the pattern of the CRS in LTE system with K2 ports, wherein K1 and K2 are positive integers greater than 0;
determining a first sequence of the first-type RS, wherein the first sequence is a sub-sequence of a second sequence of a CRS, wherein a length of the second sequence is 2N RB max,DL and a length of the first sequence is 2, wherein N RB max,DL a maximum downlink bandwidth in LTE system, wherein the determining a first sequence r l,n s (i) of the first-type RS is performed based on
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wherein the value of m i is predefined, N ID cell is a physical cell identity (PCID), n s is a time slot index, l is an orthogonal frequency-division multiplexing (OFDM) symbol index, N CP depends on a cyclic prefix (CP) type and has a value of 0 or 1, and c init is an initialization value of a pseudo-random sequence c(⋅); and
transmitting the physical downlink channel data according to the third-type RS.
2. The method of claim 1 , wherein m i ={m 0 , m 1 } when i=0 and 1 is one of the following: {0, 1}; and {N RB max,DL −1, N RB max,DL }.
3. The method of claim 1 , further comprising:
transmitting physical broadcast channel (PBCH) according to the third-type RS.
4. The method of claim 1 , wherein:
K1 is less than K2; and
the method further comprises mapping the K1 ports to the K2 ports by a transmitter according to a precoding matrix of dimension K2×K1.
5. A device, comprising:
at least one processor configured to determine a third-type reference signal (RS) based on a signaling indication,
wherein a third pattern of the third-type RS comprises a superposition of a first pattern of a first-type RS and a second pattern of a second-type RS, wherein the first pattern is a pattern for an RS of K1 ports and does not overlap with a pattern of a cell-specific reference signal (CRS) in Long Term Evolution (LTE) system and the second pattern is the pattern of the CRS in LTE system with K2 ports, wherein K1 and K2 are positive integers greater than 0,
wherein the at least one processor is further configured to obtain a first sequence of the first-type RS, wherein the first sequence is a sub-sequence of a second sequence of a CRS, wherein a length of the second sequence is 2N RB max,DL and a length of the first sequence is 2, wherein N RB max,DL is a maximum downlink bandwidth in LTE system, wherein the first sequence r l,n s (i) of the first-type RS is determined based on
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wherein the value of m i is predefined, N ID cell is a physical cell identity (PCID), n s is a time slot index, l is an orthogonal frequency-division multiplexing (OFDM) symbol index, N CP depends on a cyclic prefix (CP) type and has a value of 0 or 1, and c init is an initialization value of a pseudo-random sequence c(⋅); and
a transmitter configured to transmit the physical downlink channel data according to the third-type RS.
6. The device of claim 5 , wherein m i ={m 0 , m 1 } when i=0, and 1 is one of the following: {0, 1}; and {N RB max,DL −1, N RB max,DL }.
7. The device of claim 5 , wherein the transmission module is further configured to transmit physical broadcast channel (PBCH) according to the third-type RS.
8. The device of claim 5 , wherein:
K1 is less than K2; and
the at least one process is further configured to map the K1 ports to the K2 ports by a transmitter according to a precoding matrix of dimension K2×K1.
9. A method performed by a wireless communication device, comprising:
receiving the physical downlink channel data according to a third-type RS,
wherein a third pattern of the third-type RS comprises a superposition of a first pattern of a first-type RS and a second pattern of a second-type RS, wherein the first pattern is a pattern for an RS of K1 ports and does not overlap with a pattern of a cell-specific reference signal (CRS) in Long Term Evolution (LTE) system and the second pattern is the pattern of the CRS in LTE system with K2 ports, wherein K1 and K2 are positive integers greater than 0;
wherein the third-type reference signal (RS) is determined based on a signaling indication; and wherein the first-type RS comprises a first sequence, wherein the first sequence is a sub-sequence of a second sequence of a CRS, wherein a length of the second sequence is 2N RB max,DL and a length of the first sequence is 2, wherein N RB max,DL is a maximum downlink bandwidth in LTE system, wherein the obtaining a first sequence r l,n s (i) of the first-type RS is performed based on
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l
,
n
s
(
i
)
=
1
2
(
1
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·
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2
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)
)
+
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1
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2
·
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i
=
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1
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init
=
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10
·
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+
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+
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)
·
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2
·
N
ID
cell
+
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)
+
2
·
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ID
cell
+
N
CP
wherein the value of m i is predefined, N ID cell is a physical cell identity (PCID), n s is a time slot index, l is an orthogonal frequency-division multiplexing (OFDM) symbol index, N CP depends on a cyclic prefix (CP) type and has a value of 0 or 1, and is an initialization value of a pseudo-random sequence c(⋅).
10. The method of claim 9 , wherein m i ={m 0 , m 1 } when i=0, and 1 is one of the following: {0, 1}; and {N RB max,DL −1, N RB max,DL }.
11. The method of claim 9 , further comprising receiving physical broadcast channel (PBCH) according to the third-type RS.
12. The method of claim 9 , wherein:
K1 is less than K2; and
the method further comprises obtaining at least one equivalent channel coefficient of the K1 ports according to a precoding matrix of dimension K2×K1 and at least one estimated channel coefficient of the K2 ports.
13. A non-transitory computer-readable medium having stored thereon computer-executable instructions for carrying out any one of claims 1 - 3 , 5 , 6 - 7 , 9 and 10 - 11 .