Pilot power control technology for compensating for nonlinearity of amplifier
The disclosure relates to a method and a device for transmitting and receiving a signal by a base station or a terminal in a wireless communication system. Specifically, a method performed by a first device in a wireless communication system includes deriving an amplitude scaling factor based on a comparison between amplitude distribution of a pilot signal corresponding to a first time resource domain and the amplitude distribution of a data signal corresponding to a second time resource domain; and transmitting, to a second device, a physical channel including the pilot signal and the data signal and the amplitude scaling factor, wherein the pilot signal is transmitted with a power determined based on the amplitude scaling factor, and power compensation for the data signal is based on the amplitude scaling factor.
1. A method performed by a first device in a wireless communication system, the method comprising:
deriving an amplitude scaling factor based on a comparison between amplitude distribution of a pilot signal corresponding to a first time resource domain and amplitude distribution of a data signal corresponding to a second time resource domain; and
transmitting, to a second device, the amplitude scaling factor and a physical channel including the pilot signal and the data signal,
wherein the pilot signal is transmitted with a power determined based on the amplitude scaling factor, and
wherein power compensation for the data signal is based on the amplitude scaling factor.
2. The method of claim 1 , wherein deriving the amplitude scaling factor comprises:
multiplying the pilot signal by candidate values of amplitude scaling factors so as to identify amplitude distribution of a pilot signal corresponding to each candidate value; and
selecting, as the amplitude scaling factor, a candidate value for which a difference between a peak value of the amplitude distribution of the pilot signal corresponding to each candidate value and a peak value of the amplitude distribution of the data signal is smaller than a specific value.
3. The method of claim 1 , further comprising calculating a normalization factor for controlling a power of the data signal,
wherein the pilot signal is transmitted with a power determined based on the amplitude scaling factor and the normalization factor, and
wherein the data signal is transmitted with a power determined based on the normalization factor.
4. The method of claim 1 , wherein the amplitude scaling factor is transmitted based on downlink control information (DCI) or uplink control information (UCI).
5. The method of claim 1 , wherein the amplitude scaling factor is transmitted through the physical channel in each slot, and
wherein an amplitude scaling factor transmitted in slot (n−1) is applied to a pilot signal of a physical channel to be transmitted in slot (n).
6. The method of claim 1 , further comprising:
receiving, from the second device, a first message identifying whether power control for transmission of the physical channel is possible;
transmitting, to the second device, a second message indicating that power control for transmission of the physical channel is possible, in response to the first message;
receiving, from the second device, a third message requesting power control for transmission of the physical channel; and
increasing the power of the pilot signal and the data signal included in the physical channel, in response to the third message.
7. The method of claim 1 , further comprising transmitting, to the second device, information indicating whether deriving the amplitude scaling factor is possible.
8. A method performed by a second device in a wireless communication system, the method comprising:
receiving, from a first device, a physical channel including a pilot signal and a data signal and an amplitude scaling factor associated with power of the pilot signal; and
performing power compensation for the data signal based on the amplitude scaling factor,
wherein the amplitude scaling factor is derived based on a comparison between amplitude distribution of the pilot signal corresponding to a first time resource domain and amplitude distribution of the data signal corresponding to a second time resource domain.
9. The method of claim 8 , further comprising:
training a learning model by putting the pilot signal received from the first device into an input layer of the learning model, and applying the amplitude scaling factor to the pilot signal preconfigured in the second device and then putting the pilot signal having the applied amplitude scaling factor into an output layer of the learning model;
performing inference by putting the data signal received from the first device into the input layer of the trained learning model; and
performing power compensation for the data signal based on the inference.
10. The method of claim 8 , further comprising, after performing power compensation, performing channel estimation based on a signal obtained by dividing the pilot signal by the amplitude scaling factor.
11. A first device in a wireless communication system, the first device comprising:
a transceiver; and
a controller configured to derive an amplitude scaling factor based on a comparison between amplitude distribution of a pilot signal corresponding to a first time resource domain and amplitude distribution of a data signal corresponding to a second time resource domain, and transmit, to a second device, the amplitude scaling factor and a physical channel including the pilot signal and the data signal through the transceiver,
wherein the pilot signal is transmitted with a power determined based on the amplitude scaling factor, and
wherein power compensation for the data signal is based on the amplitude scaling factor.
12. The first device of claim 11 , wherein the controller is further configured to:
multiply the pilot signal by candidate values of amplitude scaling factors so as to identify amplitude distribution of a pilot signal corresponding to each candidate value; and
select, as the amplitude scaling factor, a candidate value for which a difference between a peak value of the amplitude distribution of the pilot signal corresponding to each candidate value and a peak value of the amplitude distribution of the data signal is smaller than a specific value.
13. The first device of claim 11 , wherein the controller is further configured to calculate a normalization factor for controlling the power of the data signal,
wherein the pilot signal is transmitted with a power determined based on the amplitude scaling factor and the normalization factor, and
wherein the data signal is transmitted with a power determined based on the normalization factor.
14. The first device of claim 11 , further comprising a power amplifier.
15. A second device in a wireless communication system, the second device comprising:
a transceiver; and
a controller configured to receive, from a first device, a physical channel including a pilot signal and a data signal and an amplitude scaling factor associated with power of the pilot signal through the transceiver, and perform power compensation for the data signal based on the amplitude scaling factor,
wherein the amplitude scaling factor is derived based on a comparison between amplitude distribution of the pilot signal corresponding to a first time resource domain and amplitude distribution of the data signal corresponding to a second time resource domain.
16. The second device of claim 15 , further comprising a learning unit configured to train a learning model by putting the pilot signal received from the first device into an input layer of the learning model, and applying the amplitude scaling factor to the pilot signal preconfigured in the second device and then putting the pilot signal having the applied amplitude scaling factor into an output layer of the learning model; and perform inference by putting the data signal received from the first device into the input layer of the trained learning model,
wherein the controller is further configured to perform power compensation for the data signal based on the inference.