I served at the first one, here--forty-six years ago!
Nice job keeping up, ChiComs!
The Germans had phased array air defense radars during World War II. It used analog circuitry, and swept a constant search pattern. It had no beam agility, and no automatic target detection. The Germans also invented the LFM waveform, using analog dispersive delay-lines, the favorite waveform of Phased-Array radar.
One of the “breakthroughs” that made PAVE PAWS economically feasible was the Werk (In-place) FFT. Werk invented and built a one-k FFT box at Raytheon, Wayland, which was the home of PAVE PAWS and BMEWS. The in-place FFT shuffles the data to use the same memory for storing the time domain and frequency domain data. It is commonplace these days. PAVE PAWS Cape Cod had an 8-K FFT, his big brothers in Thule and Flyingsdales Moor had 16-K.