Not sure what you meant in the last sentence, but I think we are in agreement. The steering comes from being able to control the phase shift of each element in a phased array. How fine (think of smallest step) you can steer depends on the fidelity of your phase shifters. The beamwidth is proportional to the antenna gain, which is again proportional to antenna size and number of elements.
For illumination, you want the beam to be narrow. How narrow depends on the range to target. What you normally don't want is to paint two targets with the same beam. If you do, your missile might decide to pass in between the two targets!
You have to define narrow whether its both in azimuth and elevation, azimuth mainly, or elevation mainly. . I think the chances of illuminating two targets on the same beam is extremely small, and you will still likely head to the nearest or bigger or faster target due to having a stronger return.
The advantage with PESA/AESA is that you can tune the beam properties dynamically and of course steer the beam electronically. The downside is that your offbore beamwidth deteriorates with the cosine of the beam angle.
Yes. AESA though, still has a long list of advantages over PESA, ranging from improved antenna gain, to the ability to alter frequencies across the array face.
Now, at extreme range you have no choice but to make the beam narrow. That's why AN/SPG-62 illuminators have beamwidths of about 0.8 degrees. The fact that it steers mechanically allows it to maintain the beamwidth regardless of pointing direction.
Still, MPQ-53, roughly 70 x 70 elements, and Thales APAR, with a 60 x 60 elements is still able to handle up to 150 km plus. On closer ranges, dividing the array into multiple beams enables the MPQ-53 to engage as many as 9 targets simultaneously, and 16 targets for the Thales APAR.
The SPG-62 has its own issues. Any form of reflecting unto a mechanical array is bound to create scatter that leads to side lobes, no matter what shape is the parabolic. You are limited in the face of saturation attack, optimally, one illuminator handles one target, guiding two missiles to the same target. A mechanical illuminator is subject to mechanical stress and wear, and it can break down. A digital illuminator has the ability to track and illuminate a target at electronic speeds, which is a crucial advantage against extremely fast and agile targets, but a mechanical illuminator is still subject to the maximum speed allowed by its mechanisms, that may not be able to keep up against a very fast moving target. 6aq2
Getting back to the Type 346. It seems many of us lean towards it being a search and tracking radar only, not unlike the SPY-1. Another forum member mentioned that the HQ-9 design was finalized two years after the 052C was launched. I would like to think that this points to very ambitious design targets.
True. Its a very ambitious direction for the PLAN.