PHASED ARRAYS

But like an immobile mirror, such an array would only cast the piggy into a constant direction; it could not scan space for missiles. So how do you revolve ten square miles of real estate round a vertical axis like the flasher on top of a police car?

You don't. Like the bottles on the water, it is all a matter of phasing the individual antennas in the array so that their radiated waves will reinforce each other in a required direction, but weaken or kill each other in all other directions. That, after all, is how the kid's mirror produced the piggy. And to phase the individual radiators is easy. A phase is a time difference, and you simply arrange (electronically) for the radio wave in the feed line to the individual antenna to wait a little until it has just the right phase. A computer can then phase the entire array to radiate in a desired direction, that is, to scan the sky systematically over all directions.

As a matter of fact, you don't even need any square miles. It is sufficient to produce two sharp beams by two very large rectangles, and then phasing the two beams so that they will produce a single beam in a desired direction while killing each other (almost) everywhere else. To see this, go back to the figure showing the phases of the electrons in the mirror. Take any two of the three for which the phase difference is shown and replace them by radio arrays which do not radiate equally in all directions, but are already beamed themselves. The phase principle will hold as before and produce a sharp radar beam (for the principle works equally well for transmission and reception) that can sweep the sky and outer space by manipulating the phases of the individual radiators.

The Soviets have built this type of phased array at Krasnoyarsk in central Asia. The figure shows a DoD artist's impression drawn from satellite photos. The two gigantic concrete blocks support the arrays of individual radio antennas to produce one beam each, and the two are then phased into the desired direction electronically.

As you can see, the physics of phased arrays is quite simple; what is vastly more difficult is to grasp the mentality of those who are expected to react to them. In a clear and massive violation of the ABM treaty, the Soviets have not only built such a phased array at Krasnoyarsk, but are now constructing two more in Latvia and Ruthenia. Yet George Shultz, when he is not either making speeches vowing never to meet with terrorists, or else meeting with terrorists who organize and openly approve of slowly burning people alive (Tambo and the ANC), still has time left for supporting the ABM treaty.

It is, after all, not certain that the thousands of antennas in the arrays are to be used for an ABM early warning system or for any Starski Warski. Until you can conclusively prove that they are not intended for voice communication with dog psychiatrists in Vladivostok, what right have you to accuse Neville Shultz of appeasement?