Method of in-band full-duplex transmission and reception, and apparatus for the same

1. An operating method of a slave node that communicates with a master node in an in-band full duplex (IFD) system, the operating method comprising:

receiving a beacon signal from the master node during a training sequence period;

transmitting a first self-interference (SI) training sequence including a first radio frequency (RF) analog SI training sequence, a first automatic gain control (AGC) sequence, and a first digital SI training sequence to the master node during the training sequence period after the beacon signal is received;

calculating a filter factor for canceling an analog SI signal input to the slave node on the basis of the first RF analog SI training sequence; and

canceling the analog SI signal from the first AGC sequence on the basis of the filter factor.

2. The operating method of claim 1 , further comprising:

adjusting gain of a data signal on the basis of strength of the beacon signal and strength of a residual SI signal remaining after the analog SI signal is canceled from the first AGC sequence;

calculating a digital filter factor for canceling the residual SI signal on the basis of the first digital SI training sequence after the gain of the data signal is adjusted; and

canceling the residual SI signal on the basis of the digital filter factor and the adjusted gain,

demodulating the data signal received from the master node according to an IFD scheme during a data transmission period after the training sequence period.

3. The operating method of claim 2 , wherein the adjusting of the gain of the data signal comprises:

calculating a third strength by adding a first strength of a desired signal measured based on the beacon signal to a second strength of the residual SI signal; and

adjusting the gain of the data signal on the basis of the third strength.

4. The operating method of claim 3 , wherein the gain of the data signal is adjusted to be within a dynamic range of an analog-to-digital converter (ADC) of the slave node.

5. The operating method of claim 1 , wherein the beacon signal includes an IFD information field and a sequence field for signal sensing and gain adjustment.

6. The operating method of claim 1 , wherein the first ACG sequence of the first SI training sequence is located between the first RF analog SI training sequence and the first digital SI training sequence.

7. The operating method of claim 2 , further receiving a second SI training sequence from the master node after transmitting the first SI training sequence,

wherein the second SI training sequence is used by the master node to cancel an SI signal, and the data signal is received from the master node during the data transmission period after the second SI training sequence is received.

8. The operating method of claim 7 , wherein the second SI training sequence includes a second RF analog SI training sequence, a second AGC sequence, and a second digital SI training sequence, and the second AGC sequence is located between the second RF analog SI training sequence and the second digital SI training sequence.

9. An operating method of a master node that communicates with a slave node in an in-band full duplex (IFD) system, the operating method comprising:

transmitting a beacon signal during a training sequence period;

receiving a first self-interference (SI) training sequence from the slave node after the slave node receives the beacon signal during the training sequence period;

transmitting a second SI training sequence including a second radio frequency (RF) analog SI training sequence, a second automatic gain control (AGC) sequence, and a second digital SI training sequence to the slave node during the training sequence period after the first SI training sequence is received;

calculating a filter factor for canceling an analog SI signal input to the master node on the basis of the second RF analog SI training sequence; and

canceling the analog SI signal from the second AGC sequence on the basis of the filter factor.

10. The operating method of claim 9 , further comprising:

adjusting gain of a data signal on the basis of strength of the first SI training sequence and strength of a residual SI signal remaining after the analog SI signal is canceled from the second AGC sequence;

calculating a digital filter factor for canceling the residual SI signal on the basis of the second digital SI training sequence after the gain of the data signal is adjusted; and

canceling the residual SI signal on the basis of the digital filter factor and the adjusted gain,

demodulating the data signal received from the slave node according to an IFD scheme during a data transmission period after the training sequence period.

11. The operating method of claim 10 , wherein the adjusting of the gain of the data signal comprises:

calculating a third strength by adding a first strength of a desired signal measured on the basis of the first SI training sequence to a second strength of the residual SI signal; and

adjusting the gain of the data signal on the basis of the third strength.

12. The operating method of claim 11 , wherein the gain of the data signal is adjusted to be within a dynamic range of an analog-to-digital converter (ADC) of the master node.

13. The operating method of claim 9 , wherein the beacon signal includes an IFD information field and a sequence field for signal sensing and gain adjustment.

14. The operating method of claim 9 , wherein the first SI training sequence includes a first RF analog SI training sequence, a first AGC sequence, and a first digital SI training sequence and is used by the slave node to cancel an SI signal.

15. A slave node that communicates with a master node in an in-band full duplex (IFD) system, the slave node comprising:

a processor; and

a memory configured to store at least one command executed by the processor,

wherein the at least one command is executed to:

receive a beacon signal from the master node during a training sequence period;

transmit a first self-interference (SI) training sequence including a first radio frequency (RF) analog SI training sequence, a first automatic gain control (AGC) sequence, and a first digital SI training sequence to the master node during the training sequence period after the beacon signal is received;

calculate a filter factor for canceling an analog SI signal input to the slave node on the basis of the first RF analog SI training sequence; and

cancel the analog SI signal from the first AGC sequence on the basis of the filter factor.

16. The slave node of claim 15 , wherein the at least one command is further executed to:

adjust gain of the data signal on the basis of strength of the beacon signal and strength of a residual SI signal remaining after the analog SI signal is canceled from the first AGC sequence;

calculate a digital filter factor for canceling the residual SI signal on the basis of the first digital SI training sequence after the gain of the data signal is adjusted; and

cancel the residual SI signal on the basis of the digital filter factor and the adjusted gain,

demodulate the data signal received from the master node according to an IFD scheme during a data transmission period after the training sequence period.

17. The slave node of claim 16 , wherein when the gain of the beacon signal is adjusted, the at least one command is executed to:

calculate a third strength by adding a first strength of a desired signal measured based on the beacon signal to a second strength of the residual SI signal; and

adjust the gain of the data signal on the basis of the third strength.

18. The slave node of claim 17 , wherein the gain of the data signal is adjusted to be within a dynamic range of an analog-to-digital converter (ADC) of the slave node.

19. The slave node of claim 15 , wherein the beacon signal includes an IFD information field and a sequence field for signal sensing and gain adjustment.

20. The slave node of claim 16 ,

wherein the at least one command is further executed to receive a second SI training sequence from the master node after transmitting the first SI training sequence; and

wherein the second SI training sequence is used by the master node to cancel an SI signal, and the data signal is received from the master node during the data transmission period after the second SI training sequence is received.