US 7,583,586 B2Granted

Apparatus and method for transmitting/receiving pilot signal in communication system using OFDM scheme

AssigneeSamsung Electronics Co., Ltd.

InventorsSung-Eun Park, Seung-Hoon Choi, Dong-Seek Park, Jae-Yoel Kim, Ji-Ho Jang, Pan-Yuh Joo

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Abstract

Disclosed is a method for transmitting a reference signal for identification of each cell in a communication system including a plurality of cells each of which is identified by a cell identifier. The method includes receiving a cell identifier, and generating a block code corresponding to the cell identifier using a predetermined block code generator matrix, and generating a first part sequence using the block code; selecting a second part sequence in accordance with the cell identifier; generating a reference signal of a frequency domain using the first part sequence and the second part sequence; converting the reference signal of the frequency domain to a reference signal of a time domain through an Inverse Fast Fourier Transform operation and transmitting the reference signal of the time domain in a predetermined reference signal transmission interval.

Claims57

Dependent claims

A method for transmitting a reference signal for identification of each cell in a communication system including a plurality of cells each of which is identified by a cell identifier, the method comprising the steps of:

in response to input of the cell identifier, generating, by a block code encoder, a block code corresponding to the cell identifier using a predetermined block code generator matrix;
generating a first part sequence by interleaving, by an interleaver, the block code according to at least one interleaving scheme and performing, by an adder, an exclusive OR operation on the interleaved block code;
selecting a second part sequence corresponding to the cell identifier and from among predetermined sequences considering Peak-to-Average Power Ratio (PAPR) reduction;
generating, by a combiner, a reference signal of a frequency domain by using the first part sequence and the second part sequence;
converting, by a transmitter, the reference signal of the frequency domain to a reference signal of a time domain through an Inverse Fast Fourier Transform (IFFT) operation;
and
transmitting, by the transmitter, the reference signal of the time domain in a over a reference signal transmission interval,
wherein the reference signal of the frequency domain is defined by:
P
ID
cell
,
S
⁡
[
k
]
=
{
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
]
)
,
k
=
2
⁢
⁢
m
-
N
used
2
,
m
=
0
,
1
,
…
⁢
,
N
used
4
-
1
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
-
1
]
)
,
k
=
2
⁢
m
-
N
used
2
,
m
=
N
used
4
+
1
,
N
used
4
+
2
,
…
⁢
,
N
used
2
0
,
otherwise
⁢
⁢
ID
cell
∈
{
0
,
1
,
…
⁢
,
126
}
,
s
∈
{
0
,
1
,
…
⁢
,
7
}
,
⁢
k
∈
{
-
N
FFT
/
2
,
-
N
FFT
/
2
+
1
,
…
⁢
,
N
FFT
⁢
2
-
1
}
,
where PIDcell,S[k] denotes the reference signal, IDcell denotes the cell identifier, s denotes a sector identifier, k denotes a sub-carrier index, Nused denotes a number of used subcarriers, NFFT denotes a number of points of the IFFT operation, and qIDcell,S[m] denotes a setup sequence.

173 more elements

An apparatus for transmitting a reference signal for identification of each cell in a communication system including a plurality of cells each of which is identified by a cell identifier, the apparatus comprising:

a block code encoder which, in response to input of the cell identifier, generates a block code corresponding to the cell identifier by using a predetermined block code generator matrix;
an interleaver for interleaving the block code according to at least one interleaving scheme;
an adder for performing an exclusive OR operation on the interleaved block code, thereby generating a first part sequence;
a combiner for generating a reference signal of a frequency domain by using the first part sequence and a second part sequence which is selected corresponding to the cell identifier and from among predetermined sequences;
and
a transmitter for converting the reference signal of the frequency domain to a reference signal of a time domain through an Inverse Fast Fourier Transform (IFFT) and, operation and then transmitting the reference signal of the time domain over a reference signal transmission interval,
where the reference signal of the frequency domain is defined by:
P
ID
cell
,
S
⁡
[
k
]
=
{
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
]
)
,
k
=
2
⁢
⁢
m
-
N
used
2
,
m
=
0
,
1
,
…
⁢
,
N
used
4
-
1
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
-
1
]
)
,
k
=
2
⁢
m
-
N
used
2
,
m
=
N
used
4
+
1
,
N
used
4
+
2
,
…
⁢
,
N
used
2
0
,
otherwise
⁢
⁢
ID
cell
∈
{
0
,
1
,
…
⁢
,
126
}
,
s
∈
{
0
,
1
,
…
⁢
,
7
}
,
⁢
k
∈
{
-
N
FFT
/
2
,
-
N
FFT
/
2
+
1
,
…
⁢
,
N
FFT
⁢
2
-
1
}
,
wherein PIDcell,S[k] denotes the reference signal, IDcell denotes the cell identifier, s denotes the sector identifier, k denotes a sub-carrier index, Nused denotes a number of used subcarriers, NFFT denotes a number of points of the IFFT operation, and qIDcell,S[m] denotes a setup sequence.

172 more elements

A method for receiving a reference signal for identification of each cell in a communication system including a plurality of cells each of which is identified by a cell identifier, the method comprising:

extracting, by a reference signal extractor, the reference signal from a received signal which has been converted through a Fast Fourier Transform (FFT) operation;
dividing, by an adder, the reference signal into a predetermined number of intervals and performing an exclusive OR (XOR) operation on the divided intervals;
deinterleaving, by a deinterleaver, the XOR-processed signal according to at least one deinterleaving scheme;
dividing, by a sub-block divider, the deinterleaved signal into sub-block signals in accordance with a predetermined block code generator matrix;
performing, by a block code decoder, an Inverse Fast Hadamard Transform (IFHT) using mask sequences generated according to control of each of the sub-block signals;
generating, by a combiner, a combined signal by combining the IFHT-processed signals for each of the sub-block signals;
and
determining, by a comparison selector, a cell identifier corresponding to a block code having a maximum correlation value from among the combined signals as a final cell identifier,
wherein the reference signal of the frequency domain is defined by:
P
ID
cell
,
S
⁡
[
k
]
=
{
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
]
)
,
k
=
2
⁢
⁢
m
-
N
used
2
,
m
=
0
,
1
,
…
⁢
,
N
used
4
-
1
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
-
1
]
)
,
k
=
2
⁢
m
-
N
used
2
,
m
=
N
used
4
+
1
,
N
used
4
+
2
,
…
⁢
,
N
used
2
0
,
otherwise
⁢
⁢
ID
cell
∈
{
0
,
1
,
…
⁢
,
126
}
,
s
∈
{
0
,
1
,
…
⁢
,
7
}
,
⁢
k
∈
{
-
N
FFT
/
2
,
-
N
FFT
/
2
+
1
,
…
⁢
,
N
FFT
⁢
2
-
1
}
,
wherein PIDcell,S[k] denotes the reference signal, IDcell denotes the cell identifier, s denotes the sector identifier, k denotes a sub-carrier index, Nused denotes a number of subcarriers used, NFFT denotes a number of points of the IFFT operation, and qIDcell,S[m] denotes a setup sequence.

174 more elements

An apparatus for receiving a reference signal for identification of each cell in a communication system including a plurality of cells each of which is identified by a cell identifier, the apparatus comprising:

a Fast Fourier Transform (FFT) unit for performing an FFT operation on a received signal;
a reference signal extractor for extracting the reference signal from the FFT-processed signal;
an adder for dividing the reference signal into a predetermined number of intervals and performing an exclusive OR (XOR) operation on the divided intervals;
a deinterleaver for deinterleaving the XOR-processed signal according to at least one deinterleaving scheme;
a sub-block divider for dividing the deinterleaved signal into sub-block signals in accordance with a predetermined block code generator matrix;
a block code decoder for performing an Inverse Fast Hadamard Transform (IFHT) using mask sequences generated according to control of each of the sub-block signals;
a combiner for generating a combined signal by combining the IFHT-processed signals for each of the sub-block signals;
and
a comparison selector for determining a cell identifier corresponding to a block code having a maximum correlation value from among the combined signals as a final cell identifier,
wherein the reference signal of the frequency domain is defined by:
P
ID
cell
,
S
⁡
[
k
]
=
{
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
]
)
,
k
=
2
⁢
⁢
m
-
N
used
2
,
m
=
0
,
1
,
…
⁢
,
N
used
4
-
1
2
⁢
(
1
-
2
⁢
⁢
q
ID
cell
,
S
⁡
[
m
-
1
]
)
,
k
=
2
⁢
m
-
N
used
2
,
m
=
N
used
4
+
1
,
N
used
4
+
2
,
…
⁢
,
N
used
2
0
,
otherwise
⁢
⁢
ID
cell
∈
{
0
,
1
,
…
⁢
,
126
}
,
s
∈
{
0
,
1
,
…
⁢
,
7
}
,
⁢
k
∈
{
-
N
FFT
/
2
,
-
N
FFT
/
2
+
1
,
…
⁢
,
N
FFT
⁢
2
-
1
}
,
where PIDcell,S[k] denotes the reference signal of the frequency domain, IDcell denotes the cell identifier, s denotes the sector identifier, k denotes a sub-carrier index, Nused denotes a number of used subcarriers, NFFT denotes a number of points of the FFT operation, and qIDcell,S[m] denotes a setup sequence.

175 more elements

A method for transmitting a reference signal for identification of each cell through at least one transmit antenna in a communication system including a plurality of cells each of which is identified by a cell identifier, the method comprising:

receiving a cell identifier;
generating, by a block code encoder, a block code corresponding to the cell identifier by using a predetermined block code generator matrix;
selecting a Walsh code corresponding to the cell identifier from among predetermined Walsh codes, and repeating the selected Walsh code a predetermined number of times;
interleaving, by an interleaver, the block code according to at least one interleaving scheme and performing, by an adder, an exclusive OR operation on the interleaved block code and the repeated Walsh code, thereby generating a first part sequence;
selecting a second part sequence corresponding to the cell identifier from among predetermined sequences;
generating, by a combiner, a reference signal of a frequency domain by using the first part sequence and the second part sequence;
and
converting, by a transmitter, the reference signal of the frequency domain to a reference signal of a time domain through an Inverse Fast Fourier Transform (IFFT) operation and then transmitting the reference signal of the time domain in a predetermined reference signal transmission interval,
wherein the reference signal of the frequency domain is defined by:
P
ID
cell
,
n
⁡
[
k
]
=
{
1
-
2
⁢
q
ID
cell
⁡
[
m
]
,
k
=
N
t
⁢
m
-
N
used
2
+
n
,
m
=
0
,
1
,
…
⁢
,
N
used
N
t
-
1
0
,
otherwise
ID
cell
∈
{
0
,
1
,
…
⁢
,
126
}
,
n
=
0
,
1
,
…
⁢
⁢
N
t
-
1
,
k
∈
{
-
N
FFT
2
,
-
N
FFT
2
+
1
,
…
⁢
,
N
FFT
2
-
1
}
,
where PIDcell,S[k] denotes the reference signal, IDcell denotes the cell identifier, n denotes an index of one of the transmit antennas, k denotes a sub-carrier index, NFFT denotes a number of points of the IFFT operation, Nused denotes a number of used subcarriers, Nt indicates a number of the transmit antennas, and qIDcell,S[m] denotes a setup sequence.

114 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/167,663Filed 27 Jun 2005
Priority: KR 10-2004-00514682 Jul 2004
Published: US 2006/0028976 A19 Feb 2006
Granted: 1 Sep 2009
Term ends: Not estimatedThe source records don’t support an estimate.

Classification12 codes

H04L 5/0048
Arrangements for allocating sub-channels of the transmission path: allocation of pilot signals, i.e. of signals known to the receiver
H04L 5/0023
Three-dimensional division: time-frequency-space
H04L 27/2613
Details of reference signals: structure of the reference signals
H04L 27/262
Peak power aspects: reduction thereof by selection of pilot symbols