So the antennae worked together to amplify each other and in doing so, increased the ability to accurately track the direction of the target?
Look at that picture and for a moment forget that there are 16 groups of 2, just consider each 2 element pair. The single set of two elements mounted one in front of the other.
What is being described is a basic 2 element Yagi-Uda antenna. It was documented and identified as a particular function in 1926 in Japan. The back element is parasitic, not active, the front element is driven, and active.
WAY oversimplified here. The energy is radiated from the front element of the pair. Some of the energy goes forward, some to the sides, and some of the energy goes back towards the other element. The energy going back gets reflected off that back element, thus the name for that element being a "reflector". That reflected energy goes forward and is added to the energy of the driven element.
This configuration produces moderate gain and directivity in the forward direction, away from the reflector and towards the driven element.
So that is a single set of two elements seen in that picture, each set of 2 is a Yagi.
But there are 16 sets of 2 elements. Each doubling of elements (2, 4, 8, 16) produces near twice as much gain (not quite double, roughly about 2.7 - 2.8 dB increase on average) and about half the beamwidth.
This vaguely sounds like a phased-array radar...
It is the basis for phased array, but it is not what we normally call phased array.
This is basically an adaptation of the lobe switching technique. By controlling the phase relationship of the energy fed to each set of 8 Yagis you can bend or steer the beam. There are 4 sets of 8, 2 sets of 8 in each plane.
So for the purposes of elevation the 16 sets are divided in two halves, top 8 and bottom 8. For the purposes of azimuth the 16 sets are divided in two halves, right 8 and left 8.
To steer the beam up slightly you slightly delay in phase the feed (energy getting to and from) to the top 8 in reference to the bottom 8. You make the signal arrive to the top 8 a little bit later in time. Often this is done by simply using slightly longer feedlines to the delayed set.
The basics of this theory was described in papers going back to the mid 1920's, and even in ham radio books by the late 1930's. Of course hams did not call it the same thing, they called them "end fire" and "broad side" arrays depending on if the elements were fed in phase or 180 degrees out of phase.
The azumuth/elevation layout is bizarre: They are exactly the opposite of how I would lay them. The elevation scope looks more like it'd display azimuth and the azimuth looks like an elevation scope.
As for azimuth: The big blip is the target, correct?
As for the elevation: The smaller blip is target, the bigger one is the ground, just to be clear?
I have attached an annotated image of how I think it works in this case.
The range display is called a J Scope. A circular representation of the entire range coverage in one sweep. In this case it starts at zero range straight up, the 12 o'clock position, and goes around clockwise to maximum range, just short of straight up at about the 11:30 position.
Notice that there is a big blip at zero range of the Range display. This is "main bang", the transmitter power is leaking into the receiver during or slightly after the on time of the transmitter.
Azimuth and Elevation are L Scopes. Azimuth appears to go from zero range at the top of the scope to maximum range at the bottom of the scope. Elevation appears to go from zero range at the left of the scope to maximum range at the right of the scope.
Note that in the attached image the target is at about 1.2 km on the Range scope, slightly to right of boresight, and slightly above boresight. So the target is slightly right and up from the aircraft, and about 1.2 km away.
Most systems using this display technique put zero range at the bottom of the Azimuth scope.
I know the FuG 202 put main bang at the bottom on its Azimuth display, so not sure why this diagram has it at the top. But then I thought the FuG 202 also put zero range on the J Scope at the bottom, or 6 o'clock position and max range at about the 4 o'clock position.
So we produced a more focused beam?
For some radars that is true. The use of microwave frequencies allowed higher gain for a given size of antenna, higher gain means smaller beamwidths, more concentrated power.
However we also had lower frequency systems with wider beamwidths, similar to the one described.
Most allied radars, particularly airborne, were at higher frequencies by mid 1943.
So, while the radar wasn't as aesthetically pleasing it was closer to a phased array than what we had?
No.
First, while the basic concept of the system is similar to Phased Array, using phase relationship to steer a beam, it is not generally called phased array in this application. Not wrong to call it so, just not what is generally meant by the term.
Second, "we" (assuming you mean Allies) used the same techniques, although typically not on aircraft. And so did the Japanese, and I think the Russians. There is no doubt, however, that the Germans used it in greater numbers and to greater affect.
Because we were working at higher frequencies we had tighter beamwidths and other ways to steer the beam, and we had no need to deploy such systems to active units. Most of our airborne systems similar to this were very early or research/experimental, we kind of jumped over this as a front line technology.
Working at the lower frequencies, and longer wavelengths, as the Germans were the antennas were physically larger for similar gain values. While it is mechanically simple to just point a small antenna it is more difficult to point a larger antenna. It was easier for us to just form a more focused, narrow, beam, and mechanically point it as needed. The Germans did not have that option.
T!