Method of data transmission in a wireless communication system
A method for transmitting data in a wireless communication system is provided. The method includes encoding one or more input data according to a specific coding rate and modulating the input data according to a specific modulation scheme, applying virtual antenna signaling to the one or more encoded and modulated input data based on a specific spatial multiplexing rate, and performing spatial processing on the input data, to which the virtual antenna signaling has been applied, and then transmitting the input data to a receiving end.
1. A method for transmitting data in a wireless communication system, the method comprising:
encoding input data to output a codeword;
modulating the codeword to output a modulated symbol stream;
mapping each symbol of the modulated symbol stream to one or more rows of an input vector to a precoder based on a specific spatial multiplexing rate;
precoding the input vector to the precoder to output a precoded vector using a phase-shift-based precoding matrix of:
P
N
t
×
R
k
=
(
ⅇ
j
θ
1
k
0
…
0
0
ⅇ
j
θ
2
k
…
0
⋮
⋮
⋱
0
0
0
…
ⅇ
j
θ
N
t
k
)
U
N
t
×
R
,
wherein P N t ×R k is the phase-shift-based precoding matrix for a k th subcarrier in a multi-antenna system with the spatial multiplexing rate of R and N t transmitting antennas, U N t ×R is a unitary matrix that satisfies “U N t ×R H ×U N t ×R =I R×R ”; and
transmitting symbols of the precoded vector to a receiving end.
2. The method according to claim 1 , wherein virtual-antenna-related information is fed back from the receiving end and the virtual-antenna-related information includes the specific spatial multiplexing rate.
3. The method according to claim 2 , wherein the virtual-antenna-related information further includes a precoding matrix information to be used by the precoder.
4. The method according to claim 3 , wherein a phase angle θ i (t)(i=1, . . . , N t ) is such that θ i =−2π/N fft ·τ i , for a delay value τ i (t)(i=1, . . . , N t ), where N fft denotes the number of subcarriers of a corresponding OFDM signal.
5. The method according to claim 2 wherein the virtual-antenna-related information fed back from the receiving end further includes unitary matrix information.
6. The method according to claim 1 , wherein the precoder uses a unitary matrix predefined according to the spatial multiplexing rate.
7. The method according to claim 1 , wherein a diagonal matrix is predefined according to the spatial multiplexing rate.