Serial feed optical approaches to phased array antennas

Photonics has been identified as an advantageous way to generate true time delays and to control phased arrays. Due to this impetus several groups have demonstrated phased arrays that were photonically controlled. Here we present the serial feed system that we have developed for optically controlling phased array antennas and discuss some of the more relevant details of these systems. This serially fed architecture offers several advantages over its counterparts such as reduced cost, minimal number of photonic components, etc. However, serial systems place great constraint on the performance of the laser. This is discussed. Finally, an implementation with optical RF phase shifters is studied which is particularly simple and versatile and promises to further reduce the complexity of the timing units in phased array systems.