Summary
International Symposium on Antennas and Propagation
2010
Session Number:3TF2
Session:
Number:3TF2-2
Investigation of a Low Profile Phased Array for Mobile Ku-Band Satcom Terminals
T.W. Ang, Y.Y. Huang, K.K. Chan,
pp.-
Publication Date:2010/11/23
Online ISSN:2188-5079
Summary:
This paper investigates the suitability of a waveguide phased array for use on mobile Kuband Satcom-on-the-move (SOTM) vehicle mounted terminals. Both receive (Rx) and transmit (Tx) arrays are considered. In order to assess the international satellite systems, the Tx array must meet certain earth station standards such as the IESS-601 [1]. For phased arrays, the most stringent of these specifications is the cross-polarization isolation or discrimination (XPD) of 26 dB within the tracking beamwidth. This level of isolation can best be met within the on-axis region of a nonscanned beam. Thus two-axes, elevation and azimuth, mechanical scanned reflector antennas or fixed-beam arrays with polarization tracking are frequently proposed. Such antenna configurations do not meet the low profile requirement in many SOTM applications. However, the Tx array is still allowed to operate but at a lower EIRP density if its XPD is better than 20 dB. Even at this level, array elements investigated in the open literature such as notch or tapered slot or patch, fail to meet the isolation required for the larger scan angles at the off-principal planes. Arrays need to employ the dual-polarized versions of these elements for electronic polarization tracking, with mechanical scan in azimuth to align the satellite along the principal planes and electronic scan in elevation for beam pointing. This is one possible approach to meet the stringent XPD requirement.