Sequence generating method for efficient detection and method for transmitting and receiving signals using the same
A method for allowing a reception end to effectively detect a sequence used for a specific channel of an OFDM communication system, and apparatus for the same are provided. During the sequence transmission, a specific part of a Zadoff-Chu sequence corresponding to the frequency “0” is omitted from a transmitted signal. In addition, first 31 constituent components of the sequence are continuously mapped to frequency resource elements of “−31” to “−1”, and the last 31 constituent components of the sequence are continuously mapped to frequency resource elements of “1” to “31”.
1. A method of transmitting signals from a transmitter to a receiver using a Zadoff-Chu sequence, the method comprising:
mapping a sequence used for a synchronization signal to a plurality of frequency resource elements to provide a frequency-domain-mapped sequence, wherein the sequence is generated from the Zadoff-Chu sequence in a frequency domain according to a predetermined root index;
converting the frequency-domain-mapped sequence into a time-domain transmission signal; and
transmitting the time-domain transmission signal to the receiver,
wherein:
the time-domain transmission signal is transmitted by omitting a specific component from the Zadoff-Chu sequence corresponding to a center of the Zadoff-Chu sequence;
a length of the Zadoff-Chu sequence is 63;
first 31 constituent components of the Zadoff-Chu sequence are continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “−31” to “−1”; and
last 31 constituent components of the Zadoff-Chu sequence are continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “1” to “31”.
2. The method according to claim 1 , wherein the time-domain transmission signal is transmitted after puncturing the specific component from the Zadoff-Chu sequence.
3. The method according to claim 1 , wherein the Zadoff-Chu sequence is used as a primary synchronous channel (P-SCH) transmission sequence.
4. The method according to claim 1 , wherein the specific component from the Zadoff-Chu sequence corresponds to a component from the Zadoff-Chu sequence that is mapped to a zero frequency value.
5. A transmitter for transmitting signals to a receiver using a Zadoff-Chu sequence, the transmitter comprising:
a mapper configured to:
receive a sequence generated from the Zadoff-Chu sequence in a frequency domain according to a predetermined root index; and
map the generated sequence to frequency resource elements;
an IFFT module configured to convert the frequency-domain-mapped sequence into a time-domain transmission signal; and
a radio-frequency (RF) module configured to transmit the time-domain transmission signal to the receiver,
wherein:
the time-domain transmission signal is transmitted by omitting a specific component from the Zadoff-Chu sequence corresponding to a center of the Zadoff-Chu sequence;
a length of the Zadoff-Chu sequence is 63;
first 31 constituent components of the Zadoff-Chu sequence are continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “−31” to “−1”; and
last 31 constituent components of the Zadoff-Chu sequence are continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “1” to “31”.
6. The transmitter according to claim 5 , wherein the time-domain transmission signal is transmitted after puncturing the specific component from the Zadoff-Chu sequence.
7. The transmitter according to claim 5 , wherein the Zadoff-Chu sequence is used as a P-SCH (Primary-SCH) transmission sequence.
8. The transmitter according to claim 5 , wherein the specific component from the Zadoff-Chu sequence corresponds to a component from the Zadoff-Chu sequence that is mapped to a zero frequency value.
9. A method of detecting a sequence used in a received (Rx) signal by a receiver in a mobile communication system, the method comprising:
receiving the Rx signal from a transmitter, wherein the Rx signal is a time-domain signal; and
detecting the sequence used in the Rx signal,
wherein:
the time-domain signal was transmitted from the transmitter by omitting a specific component from a Zadoff-Chu sequence corresponding to a center;
a length of the Zadoff-Chu sequence is 63;
first 31 constituent components of the Zadoff-Chu sequence were continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “−31” to “−1”; and
last 31 constituent components of the Zadoff-Chu sequence were continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “1” to “31”.
10. The method according to claim 9 , wherein the Zadoff-Chu sequence is used as a P-SCH (Primary-SCH) sequence.
11. A receiver for detecting a sequence used in a received (Rx) signal in a mobile communication system, the receiver comprising:
a radio-frequency (RF) module configured to receive the Rx signal from a transmitter, wherein the Rx signal is a time-domain signal; and
an index demapper configured to detect the sequence used in the Rx signal,
wherein:
the time-domain signal was transmitted from the transmitter by omitting a specific component from a Zadoff-Chu sequence corresponding to a center of the Zadoff-Chu sequence;
a length of the Zadoff-Chu sequence is 63;
first 31 constituent components of the Zadoff-Chu sequence were continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “−31” to “−1”; and
last 31 constituent components of the Zadoff-Chu sequence were continuously mapped to a plurality of frequency resource elements corresponding to frequency resource element indices within a range of “1” to “31”.
12. The receiver according to claim 11 , wherein the Zadoff-Chu sequence is used as a P-SCH (Primary-SCH) sequence.