Method and apparatus for transmitting or detecting a primary synchronization signal
A method and apparatus for transmitting or detecting primary synchronization signal. The receiver receives primary synchronization signal from a transmitter, and detects the sequence used in the received primary synchronization signal by using three root indexes. Here, the primary synchronization signal is generated by using a Zadoff-Chu sequence having one of the three root indexes. The three root indexes comprise a first index and a second index, and a sum of the first index and the second index corresponds to the length of the Zadoff-Chu sequence.
1. A method of detecting a sequence used in a primary synchronization signal by a receiver in a mobile communication system, the method comprising:
receiving the primary synchronization signal from a transmitter; and
detecting the sequence used in the received primary synchronization signal by using 3 root indexes,
wherein the primary synchronization signal is generated by using a Zadoff-Chu sequence having one of the 3 root indexes,
wherein the 3 root indexes comprise a first index and a second index, and
wherein a sum of the first index and the second index corresponds to a length of the Zadoff-Chu sequence.
2. The method of claim 1 ,
wherein the Zadoff-Chu sequence has an odd number length, and
wherein an equation for generating the sequence from the Zadoff-Chu sequence is based on the following equation:
exp
(
-
ⅈ
M
π
n
(
n
+
1
)
N
)
wherein the length of the Zadoff-Chu sequence is “N”, “M” is the root index of the Zadoff-Chu sequence, and “n” is an index of each of constituent components of the generated sequence.
3. The method of claim 2 ,
wherein “N” is 63, and
wherein the first index and the second index correspond to root indexes of 34 and 29, respectively.
4. The method of claim 1 , wherein the 3 root indexes further comprise a third index corresponding to a root index of 25.
5. The method of claim 1 , further comprising performing synchronization with the transmitter based on the detected sequence used in the received primary synchronization signal.
6. A method of transmitting a primary synchronization signal to a receiver by a transmitter in a mobile communication system, the method comprising:
mapping a sequence generated by using a Zadoff-Chu sequence having a root index to frequency domain indexes to be used for the primary synchronization signal,
wherein the root index is selected from among 3 root indexes,
wherein the 3 root indexes comprise a first index and a second index, and
wherein a sum of the first index and the second index corresponds to a length of the Zadoff-Chu sequence; and
transmitting the primary synchronization signal using the mapped sequence to the receiver.
7. The method of claim 6 ,
wherein the Zadoff-Chu sequence has an odd number length, and
wherein an equation for generating the sequence from the Zadoff-Chu sequence is based on the following equation:
exp
(
-
ⅈ
M
π
n
(
n
+
1
)
N
)
wherein the length of the Zadoff-Chu sequence is “N”, “M” is the root index of the Zadoff-Chu sequence, and “n” is an index of each of constituent components of the generated sequence.
8. The method of claim 7 ,
wherein “N” is 63, and
wherein the first index and the second index correspond to root indexes of 34 and 29, respectively.
9. The method of claim 6 , wherein the 3 root indexes further comprise a third index corresponding to a root index of 25.
10. A receiver for detecting a sequence used in a primary synchronization signal in a mobile communication system using orthogonal frequency division multiplexing (OFDM), the receiver comprising:
a radio frequency module configured to receive the primary synchronization signal from a transmitter; and
an index demapper configured to detect the sequence used in the received primary synchronization signal by using 3 root indexes,
wherein the primary synchronization signal is generated by using a Zadoff-Chu sequence having one of the 3 root indexes,
wherein the 3 root indexes comprise a first index and a second index, and
wherein a sum of the first index and the second index corresponds to a length of the Zadoff-Chu sequence.
11. The receiver of claim 10 ,
wherein the Zadoff-Chu sequence has an odd number length, and
wherein an equation for generating the sequence from the Zadoff-Chu sequence is based on the following equation:
exp
(
-
ⅈ
M
π
n
(
n
+
1
)
N
)
wherein the length of the Zadoff-Chu sequence is “N”, “M” is the root index of the Zadoff-Chu sequence, and “n” is an index of each of constituent components of the generated sequence.
12. The receiver of claim 11 ,
wherein “N” is 63, and
wherein the first index and the second index correspond to root indexes of 34 and 29, respectively.
13. The receiver of claim 10 , wherein the 3 root indexes further comprise a third index corresponding to a root index of 25.
14. A transmitter for transmitting a primary synchronization signal to a receiver in a mobile communication system using orthogonal frequency division multiplexing (OFDM), the transmitter comprising:
a mapping module configured to map a sequence generated by using a Zadoff-Chu sequence having a root index to frequency domain indexes to be used for the primary synchronization signal,
wherein the root index is selected from among 3 root indexes,
wherein the 3 root indexes comprise a first index and a second index, and
wherein a sum of the first index and the second index corresponds to a length of the Zadoff-Chu sequence;
an Inverse Fast Fourier Transform (IFFT) module configured to generate a time-domain transmission signal from the sequence mapped to the frequency domain indexes; and
a radio frequency (RF) module configured to transmit the time-domain transmission signal to the receiver as the primary synchronization signal.
15. The transmitter of claim 14 ,
wherein the Zadoff-Chu sequence has an odd number length, and
wherein an equation for generating the sequence from the Zadoff-Chu sequence is based on the following equation:
exp
(
-
ⅈ
M
π
n
(
n
+
1
)
N
)
wherein the length of the Zadoff-Chu sequence is “N”, “M” is the root index of the Zadoff-Chu sequence, and “n” is an index of each of constituent components of the generated sequence.
16. The transmitter of claim 15 ,
wherein “N” is 63, and
wherein the first index and the second index correspond to root indexes of 34 and 29, respectively.
17. The transmitter of claim 15 , wherein the 3 root indexes further comprise a third index corresponding to a root index of 25.