I calculated array factor for patch antenna for fixed steering angle array, with distance between patches (dx). By summing up each element
along (x) axis with additional phase shift (phs). As F2(t,p,1,0,0) +F2(t,p,2,0,1) +F2(t,p,3,0,2) + etc.
F2(theta,phi,x,y,n)=Exp(-i*2*Pi*((x)*dx)*Sin(theta)*Cos(phi)) *Exp(-i*2*Pi*(y*dy)*Sin(theta)*Sin(phi)) *Exp(i*
*phs*Pi/180);
And surprisingly obtained resulting angle exactly as in papers i learned from. Also i used Sonnet lite to simulate small part of antenna to see something interesting. As true patch sizes was unknown, i started from single patch, and tuned it height to obtain center frequency. When i connected patches in series array, S11 center frequency moved up by 500MHz. Unsure how to interpret it, maybe it is field influence you mentioned. If it is true, then my S11 result is so different because of this. Also i removed autognd port and moved feeding line directly to box wall, and it seems to calculate faster, and results are similar. But now i have an error message:
Sonnet Warning EG2550:
Potential problem with circuit.
Bottom box-wall reference plane may extend beyond a discontinuity.
Here is small example of three elements series fed array:
I come to conclusion that series fed array beam angle is very sensitive to feeding frequency. While corporate feed gives in-phase feed for every patch even if center frequency is shifted. It is strange to me why most modern sensors with VCO ability use series fed (not as on my image, a little different), as they have modulation around 200MHz. For wide band sensors corporate seems more appropriate, for single frequency CW sensor series fed is good to make good power dividing for reduce side beams.