A beamformer for forming a reception beam using a multichannel signal reflected from a subject and converted into an electric signal, the beamformer comprising: a signal generator configured to generate a plurality of signals by applying a plurality of different apodization functions to the converted multichannel signal; an estimator configured to estimate a signal predominant component and a noise predominant component from the plurality of signals; a weight calculator configured to calculate a weight to be applied to the signal predominant component according to each of the channels, based on the estimated signal predominant component and the estimated noise predominant component; and a weight applier configured to apply the calculated weight to the estimated signal predominant component; wherein the signal generator comprises: a first signal generator configured to generate a first signal by applying a first apodization function to the converted multichannel signal; and a second signal generator configured to generate a second signal by applying a second apodization function to the converted multichannel signal; wherein the estimator comprises: a signal predominant component estimator configured to estimate the signal predominant component by calculating a sum of the first and second signals; and a noise predominant component estimator configured to estimate the noise predominant component by calculating a difference between the first and second signals. a signal generator configured to generate a plurality of signals by applying a plurality of different apodization functions to the converted multichannel signal; an estimator configured to estimate a signal predominant component and a noise predominant component from the plurality of signals; a weight calculator configured to calculate a weight to be applied to the signal predominant component according to each of the channels, based on the estimated signal predominant component and the estimated noise predominant component; and a weight applier configured to apply the calculated weight to the estimated signal predominant component; wherein the signal generator comprises: a first signal generator configured to generate a first signal by applying a first apodization function to the converted multichannel signal; and a second signal generator configured to generate a second signal by applying a second apodization function to the converted multichannel signal; wherein the estimator comprises: a signal predominant component estimator configured to estimate the signal predominant component by calculating a sum of the first and second signals; and a noise predominant component estimator configured to estimate the noise predominant component by calculating a difference between the first and second signals. a first signal generator configured to generate a first signal by applying a first apodization function to the converted multichannel signal; and a second signal generator configured to generate a second signal by applying a second apodization function to the converted multichannel signal; wherein the estimator comprises: a signal predominant component estimator configured to estimate the signal predominant component by calculating a sum of the first and second signals; and a noise predominant component estimator configured to estimate the noise predominant component by calculating a difference between the first and second signals. a signal predominant component estimator configured to estimate the signal predominant component by calculating a sum of the first and second signals; and a noise predominant component estimator configured to estimate the noise predominant component by calculating a difference between the first and second signals.