Phased-array and radar astounding breakthroughs — an update

In recent years phased arrays have seen breakthroughs that lead to capabilities not possible in the past. This is exemplified by the development of GaAs integrated microwave circuits called monolithic microwave integrated circuits (MMIC). This integration has reached the point where it is possible to now build a low cost 35 GHz phased array for a missile seeker costing $30/element (total cost of array including all electronics divided by number of elements). This is made possible here because integration allows the whole T/R module to be put on a single chip. For some application it will be possible in the near future to put multiple receivers or transmitters on a single chip now. The advances provided by Moorepsilas Law has now made it is feasible to do digital beam forming (DBF) with all its numerous advantages. It is now possible to do DBF for a 2,500 element array at the element level, a major breakthrough. Also covered will be: the potential for GaN and SiC chips which have the capability of a factor of ten or more higher peak power than GaAs chips; arrays with instantaneous bandwidths of up to 33:1; SiGe low cost T/R modules; low cost MEMS passive arrays; a real radar application for multiple-input multiple-output (MIMO) as opposed to fantasy has been demonstrated by Lincoln Lab MIT which allows coherent combining of two radars to achieve a 9 dB increase in sensitivity; MIMO also makes possible the optimum removal of clutter in OTH and airborne radars by permitting adaptive control of the transmit antenna pattern in the receiver.