I/Q demodulator and I/Q signal sampling method thereof

1. An In-phase/Quadrature-phase (I/Q) demodulator, comprising:

a delay unit which delays an input data signal and outputs a delayed input signal;

first and second decimation units which decimate the input data signal and the delayed input signal, respectively;

a first multiplexer which multiplexes the decimated delayed input data signal and a negative of the delayed input signal to output an I signal;

a second multiplexer which multiplexes the decimated non-delayed input data signal and a negative of the non-delayed input signal to output a Q signal; and

first and second filters which filter the I and Q signals, to output effective I and Q signals, respectively.

2. The I/O demodulator of claim 1 , wherein the first and second decimation units perform a 2-decimation.

3. The I/O demodulator of claim 1 , further comprising:

first and second L-upsampling units which L-upsample the I and Q signals output from the first and second multiplexers to provide the upsampled I and Q signals to the first and second filters; and

first and second M-downsampling units which M-downsample the filtered I and Q signals.

4. The I/Q demodulator of claim 3 , wherein the L of each L-upsampling unit is odd.

5. The I/Q demodulator of claim 3 , wherein the L of each L-upsampling unit is even.

6. The I/Q demodulator of claim 1 , wherein:

the first multiplexer sequentially outputs the input data signal, a zero, a negative of the input data signal and a zero; and

the second multiplexer sequentially outputs a zero, the input data signal, a zero and a negative of the input data signal.

7. An In-phase/Quadrature-phase (I/Q) demodulator, comprising:

a delay unit which delays an input data signal and outputs a delayed input signal;

first and second decimation units which decimate the input data signal and the delayed input signal, respectively;

a first multiplexer which multiplexes the decimated delayed input data signal and a negative of the delayed input signal to output an I signal;

a second multiplexer which multiplexes the decimated non-delayed input data signal and a negative of the non-delayed input signal to output a Q signal;

first and second upsampling units which upsample the I and Q signals, respectively;

first and second filters which filter the upsampled I and Q signals, respectively; and

first and second M-downsampling units which downsample the filtered I and Q signals, respectively, to output effective I and Q signals, respectively.

8. The I/O demodulator of claim 7 , wherein the M of each M-downsampling unit is even.

9. The I/Q demodulator of claim 7 , wherein the M of each M-upsampling unit is odd.

10. An In-phase/Quadrature-phase (I/Q) demodulator, comprising:

a first multiplexer which multiplexes an input signal and other signals to output an I signal;

a second multiplexer which multiplexes the input signal and the other signals to output a Q signal;

first and second upsampling units which upsample the I and Q signals, respectively;

first and second delay units which delay the upsampled I and Q signals, respectively;

first and second decimation units which decimate the delayed I and Q signals, respectively;

first and second low pass filters which filter the decimated I and Q signals; and

first and second M-downsampling units which M-downsample the low pass filtered I and Q signals, to output effective I and Q signals, wherein the M of each M-downsampling unit is even.

11. The I/O demodulator of claim 10 , wherein:

the first multiplexer sequentially outputs the input data signal, a zero, a negative of the input data signal and a zero; and

the second multiplexer sequentially outputs a zero, the input data signal, a zero and a negative of the input data signal.

12. An In-phase/Quadrature-phase (I/Q) demodulator, comprising:

a first multiplexer which multiplexes an input signal and other signals to output an I signal;

a second multiplexer which multiplexes the input signal and the other signals to output a Q signal;

first and second upsampling units which upsample the I and Q signals, respectively;

a delay unit which delays the upsampled I signal;

first and second decimation units which decimate the delayed I signal and the Q signal, respectively;

first and second low pass filters which filter the decimated delayed I signal and the decimated Q signal, respectively; and

first and second M-downsampling units which M-downsample the filtered decimated delayed I signal and the filtered decimated Q signal, to output effective I and Q signals, respectively, wherein the M of each M-downsampling unit is odd.

13. The I/Q demodulator of claim 12 , wherein:

the first multiplexer sequentially outputs the input data signal, a zero, a negative of the input data signal and a zero; and

the second multiplexer sequentially outputs a zero, the input data signal, a zero and a negative of the input data signal.

14. An In-phase/Quadrature-phase (I/Q) signal generating method, comprising:

delaying an input data signal and outputting a delayed input signal;

decimating the input data signal and the delayed input signal, respectively;

multiplexing the decimated delayed input data signal and a negative of the delayed input signal to output an I signal;

multiplexing the decimated non-delayed input signal and a negative of the non-delayed input signal to output a Q signal; and

filtering the I and Q signals, to output effective I and Q signals, respectively.

15. The I/Q signal generating method of claim 14 , further comprising:

L-upsampling the I and Q signals output; and

M-downsampling the filtered I and Q signals.

16. The I/Q signal generating method of claim 15 , wherein the L of the L-upsampling is odd.

17. The l/Q signal generating method of claim 15 , wherein the L of the L-upsampling is even.

18. The I/O signal generating method of claim 14 , wherein the decimating performs a 2-decimation.

19. The I/Q signal generating method of claim 14 , wherein:

the I signal is sequentially output as the input data signal, a zero, a negative of the input data signal and a zero; and

the Q signal is sequentially output as a zero, the input data signal, a zero and a negative of the input data signal.

20. An In-phase/Quadrature-phase (I/Q) signal generating method, comprising:

delaying an input data signal and outputting a delayed input data signal;

decimating the input data signal and the delayed input signal, respectively;

multiplexing the decimated delayed input data signal and a negative of the delayed input signal to output an I signal and a Q signal;

upsampling the I and Q signals, respectively;

filtering the upsampled I and Q signals, respectively; and

downsampling the filtered I and Q signals, respectively, to output effective I and Q signals, respectively.