Wideband radiation enhancement of waveguide arrays operated as feeds for reflector antennas using patch array covers

Abstract

[1] This work rigorously analyzes a periodic microstrip patch array printed on a dielectric slab and placed over an array of open-ended sidewall loaded rectangular waveguides. The method of moments using spectral Green's functions for multilayer structures is employed. The application selected to feature the computed results of this structure is array matching. This work thus investigates the ability of such patch arrays to improve the transmission levels of waveguide arrays over those of uncovered ones. The matching performance is also compared with conventional dielectric sheath-type tuners. Two array operation scenarios are studied: direct radiating phased arrays, and focal plane arrays as feeds for reflectors. Earlier studies of the latter scenario show that the decoupling efficiency tends to be poor at low frequencies, due to the electrical proximity between the waveguide elements. It will be demonstrated here that both forms of matching layers can be tuned to provide good matching at low frequencies. This study has opted to investigate the beneficial effects of the sheet and the patch array over a wide frequency band, rather than its optimization over a selected narrow band. Such optimizations can be done in practice for known specific operating bands.Citation: Ng Mou Kehn, M., and L. Shafai (2010), Wideband radiation enhancement of waveguide arrays operated as feeds for reflector antennas using patch array covers, Radio Sci., 45, RS1006,

A focusing reflectarray and its application in microwave virus sanitizer

“…Moreover, the radiated fields are collimated to the desired direction in the far zone [Pan et al, 2009], which makes it unsuitable for the microwave virus sanitizer. As for the focusing antennas, reflector antennas [Rahat-Samii and Galindo-Israel, 1980;Menzel et al, 2002;Mou Kehn and Shafai, 2010;Harun and Ellingson, 2011] and lens antennas, including the microwave counterparts of the optical lens [Wang et al, 2013], are two major antenna types, and both are capable of concentrating microwave power onto a specific point or collimating the fields to a specific far-field direction. However, conventional reflector antennas and lens antennas are very bulky, heavy, and expensive.…”