APPA: A Phased Array System Designed for Space Application Nitardy, John ; Preikschat, Fritz ; Ritchey, Orral ; Sandrin, William Abstract Publication: IEEE Transactions on Aerospace Electronic Systems Pub Date: July 1970 DOI: 10.1109/TAES.1970.310141 Bibcode: 1970ITAES...6..575N