Delay Sum Beamforming of four microphone signals to detect the presence of drone

Hi.

I am using four-microphone array, to localize drone. I did localize sound captured by these four-microphone.

now my mentor want to validate the presence of drone (single source) in that sound which i localized.

I did get useful frames and now i want apply this four microphone data for beamforming for varification of my true localization that sound is coming form one single source.

How can i use these four channel data for beamfroming.

I need help and simple solution using conventional beamformer like. DSB(delay sum beamformer).

Fs = 32000;

array elements = 4;

spacing of microphone = 0.5;

sound speed= 343;

wavelength = 0.106;

microphone postion L = 0.45;

H = 0.57;

m1 = [0 0 H];

m2 = [L 0 0];

m3 = [-L/2 -sqrt(3)*L/2 0];

m4 = [-L/2 sqrt(3)*L/2 0];

distance of target = 50;

theta = [-180 180];

phi = [0 90];

soundsrc = [d*cos(varphi)*cos(theta), d*cos(varphi)*sin(theta), d*sin(varphi)];

Please researhers facilitate me a suitable and simple solution. Thanks.