Beam transmitting device and operating method of the same

An operating method of a beam transmitting device, the operating method comprising:

• transmitting, by the beam transmitting device, a null data packet;
• receiving, by the beam transmitting device, channel information, wherein the channel information is sent by a beam receiving device after a reception of the null data packet;
• obtaining, based on an interpolation of the channel information, a plurality of beamforming vectors;
• calculating, by a weight calculator, a common phase factor using the plurality of beamforming vectors;
• obtaining a weighted plurality of beamforming vectors by the weight calculator by applying the common phase factor to the plurality of beamforming vectors;
• calculating, by a moving average filter, a moving average of the weighted plurality of beamforming vectors;
• and
• transmitting a waveform based on the moving average of the weighted plurality of beamforming vectors, a preamble and data.

A beam transmitting device comprising:

• a beamformer configured to form a beam;
• a transmitter configured to transmit, using the beam, a null data packet;
• a controller configured to control a preamble in the null data packet;
• an interpolator configured to:
• interpolate channel information, wherein the channel information is sent by a beam receiving device after a reception of the null data packet, and
• obtain, based on the interpolated channel information, a plurality of beamforming vectors;
• and
• a smoothing circuit configured to smooth the plurality of beamforming vectors,
• wherein the smoothing circuit includes:
• a weight calculator configured to obtain a weighted plurality of beamforming vectors based on a common phase factor;
• a comparator configured to compare a value with a threshold to determine whether to perform smoothing, the value derived using two adjacent beamforming vectors among the plurality of beamforming vectors;
• and
• a moving average filter configured to smooth by forming a moving average using the common phase factor based on an output of the comparator.