True time delay challenge in optically controlled phased array antennas

Optically fed phased array antennas are a viable solution to realize multibeam antennas for future generation of communication satellites. Squint free beam generation in phased array is assured using true time delay (TTD) elements. Major efforts of the last couple of years are to investigate various realizations of the TTD elements such that a high beam pointing accuracy is obtained. Most system realizations are directed toward demonstration of various TTD realizations. However, the critical problem of design innovations to reduce the overall size and loss associated with TTD has not been addressed. A high beam pointing accuracy could be realized without the need for high resolution TTD elements. We demonstrate this critical point by emphasizing one of the inherent benefits of a T/R level data mixing architecture over the CPU level one.