Accurate synthesis of linear non-resonant narrow wall inclined slotted waveguide arrays

An efficient and highly accurate network model for analysing and synthesising large but finite slotted waveguides (SWGs) is presented. The network model is tailored for arrays of linear end-fed narrow wall inclined slots. The network model accurately predicts, as function of frequency, the key electrical antenna parameters such as antenna-radiation pattern (beamwidth, inner and spurious sidelobes down to the -40-dB level, main beam squint), waveguide loss, power dissipated in the load and return loss. The network model explicitly takes mechanical tolerances into account. The model is based upon S-parameter measurements of a number of test-SWGs. The network model has been proven to be scalable from X-band to S-band waveguides and can be extrapolated to slot parameters far beyond the range of the slots of the test-SWGs. The comparison between predicted and measured results has shown that the network model is highly accurate, providing a significant improvement over full wave commercial tools in terms of prediction of the antenna parameters of interest as well as in computational speed.