求论文几篇，能下的朋友帮个忙: dual-band reflecto-feed element for frequency-reuse applications.pdf

1. 宽频带的双环扼流波导馈源  1983天线年会论文集 作者：唐大强 柯树人
2.dual-band reflecto-feed element for frequency-reuse applications,  electronics letters.
3.beamwidth variation with  aperture diameter of the choked waveguide feed antenna, electronics letters.
4.radiation properties of 90° conical horns, electronics letters.