Method and device for performing communication using orthogonal or nonorthogonal code multiple access scheme in wireless communication system
Provided are a method and a device for transmitting uplink data by using a non-orthogonal code multiple access scheme in a wireless communication system. Specifically, a terminal receives information on a terminal-specific codebook from a base station. The terminal-specific codebook is included in a codebook for a predefined multi-dimensional modulation. The terminal performs multi-dimensional modulation-based encoding on an information bit on the basis of the terminal-specific codebook so as to generate a complex vector. The terminal performs DFT on the complex vector on the basis of the terminal-specific codebook so as to generate a frequency signal. The terminal transmits uplink data generated by performing IFFT on the frequency signal.
1. A method for transmitting uplink data based on Non-orthogonal Multiple Access (NoMA) in a wireless communication system, comprising:
receiving, by a user equipment (UE), information on a UE specific codebook from a base station, wherein the UE specific codebook is included in a pre-defined codebook for Multi-dimensional Modulation;
generating, by the UE, a complex vector by performing Multi-dimensional Modulation based encoding on information bits based on the UE specific codebook;
generating, by the UE, a frequency signal by performing Discrete Fourier Transform (DFT) on the complex vector based on the UE specific codebook; and
transmitting, by the UE, uplink data being generated by performing Inverse Fast Fourier Transform (IFFT) on the frequency signal,
wherein the UE specific codebook is determined as one of first to sixth codebooks,
wherein the first codebook is defined as shown below:
[
0
0
0
0
1
1
-
1
-
1
0
0
0
0
1
-
1
1
-
1
]
*
P
no
,
wherein the second codebook is defined as shown below:
[
1
1
-
1
-
1
0
0
0
0
1
-
1
1
-
1
0
0
0
0
]
*
P
no
,
wherein the third codebook is defined as shown below:
[
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
0
0
0
0
0
0
0
0
]
*
P
no
,
wherein the fourth codebook is defined as shown below:
[
0
0
0
0
0
0
0
0
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
]
*
P
no
,
wherein the fifth codebook is defined as shown below:
[
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
0
0
0
0
0
0
0
0
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
]
*
P
no
,
wherein the sixth codebook is defined as shown below:
[
0
0
0
0
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
0
0
0
0
]
*
P
no
,
wherein the P no is a M×M matrix being normalized for power limitation and defined as shown below:
P
n
o
=
[
P
no
,
1
l
0
0
0
0
P
no2
,
0
0
0
0
P
no
,
3
0
0
0
0
P
no
,
4
]
.
,
wherein a size of each coefficient is equal in a mother constellation being used for configuring the first to sixth codebooks, and
wherein the mother constellation is a row vector of the first to sixth codebooks having non-zero coefficients, and
wherein the P no,m is defined as shown below:
P no,m =(1/|vec m|)×√K, for m=1, . . . , M, where K=4, M=4.
2. The method of claim 1 , wherein a codeword of the first to sixth codebooks is a column vector of the first to sixth codebooks, and
wherein, among the codewords, part of the codewords include non-zero coefficients having inverted phases and being adjacent.
3. The method of claim 1 , wherein, in case the UE is located on a cell-edge, the UE specific codebook is determined as a codebook having a low Peak-to-Average Power Ratio (PAPR) value, and
wherein, in case the UE is located on a cell-center, the UE specific codebook is determined as a codebook having a high PAPR value.
4. The method of claim 1 , wherein the DFT is performed in a case where a DFT block of the UE is active, and
wherein the DFT block of the UE is active or in-active based on a UE specific codebook being included in a codebook being pre-defined for the Multi-dimensional Modulation.
5. A user equipment (UE) for transmitting uplink data based on Non-orthogonal Multiple Access (NoMA) in a wireless communication system, comprising:
a transceiver transmitting and receiving radio signals; and
a processor being operatively connected to the transceiver,
wherein the processor is configured:
to receive information on a UE specific codebook from a base station, wherein the UE specific codebook is included in a pre-defined codebook for Multi-dimensional Modulation,
to generate a complex vector by performing Multi-dimensional Modulation based encoding on information bits based on the UE specific codebook,
to generate a frequency signal by performing Discrete Fourier Transform (DFT) on the complex vector based on the UE specific codebook, and
to transmit uplink data being generated by performing Inverse Fast Fourier Transform (IFFT) on the frequency signal,
wherein the UE specific codebook is determined as one of first to sixth codebooks,
wherein the first codebook is defined as shown below:
[
0
0
0
0
1
1
-
1
-
1
0
0
0
0
1
-
1
1
-
1
]
*
P
no
,
wherein the second codebook is defined as shown below:
[
1
1
-
1
-
1
0
0
0
0
1
-
1
1
-
1
0
0
0
0
]
*
P
no
,
wherein the third codebook is defined as shown below:
[
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
0
0
0
0
0
0
0
0
]
*
P
no
,
wherein the fourth codebook is defined as shown below:
[
0
0
0
0
0
0
0
0
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
1
*
e
j
*
1
3
π
-
1
*
e
j
*
1
3
π
]
*
P
no
,
wherein the fifth codebook is defined as shown below:
[
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
0
0
0
0
0
0
0
0
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
]
*
P
no
,
wherein the sixth codebook is defined as shown below:
[
0
0
0
0
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
1
*
e
j
*
2
3
π
-
1
*
e
j
*
2
3
π
0
0
0
0
]
*
P
no
,
wherein the P no is a M×M matrix being normalized for power limitation and defined as shown below:
P
no
=
[
P
no
,
1
0
0
0
0
P
no
,
2
0
0
0
0
P
no
,
3
0
0
0
0
P
no
,
4
]
.
,
wherein a size of each coefficient is equal in a mother constellation being used for configuring the first to sixth codebooks, and
wherein the mother constellation is a row vector of the first to sixth codebooks having non-zero coefficients, and
wherein the P no,m is defined as shown below:
P no,m =(1/|vec m|)×√K, for m=1, . . . , M, where K=4, M=4.