A 7.5-GHz microstrip phased array for aircraft-to-satellite communication

A New Amplitude and Phase Control Concept for Microstrip Phased Array Antennas

“…The main design goal was to gain control of the global phase of the antenna fields without significantly changing the radiation pattern and polarisation at the operational frequency. Disregarding the radiation part of the problem in a first step of design, a loading of a two-port-antenna at one terminal (port 1, rload) produces an input reflection coefficient at port 1 according to: s1 s 21rla r1 =11 + 1 2 rload (1) 122 load (s11' 12' s2i' s22 scattering parameters of the antenna) This reflection coefficient then may be compared to the input reflection r1' of the same antenna element without the load at port 2 (open, rload = 1), but with an attenuator (a), phase-shifter (+) configuration in the feeding branch ( fig. 1).…”