New radio wave technologies of millimeter-wave (mmWave), compact cell size, and multi beam base station are introduced with the recent development 5G mobile system. The Butler Matrix (BM) feed circuit is most preferable candidate for system since it can achieve radiationpatterns at array antenna, provide structural compactness produce good beams.The BM typically built on a single dielectric sub...

Warped products provide a rich class of physically significant geometric objects. Warped product construction is an important method to produce a new metric with a base manifold and a fibre. We construct compact base manifolds with a positive scalar curvature which do not admit any non-trivial quasi-Einstein warped product, and non compact complete base manifolds which do not admit any non-triv...

An ultra-wideband (UWB), geometrically simple, compact, and high-gain antenna with a WLAN notch band is presented for future wireless devices. The printed on the top side of Rogers RT/Duroid 5880 substrate has small dimension 10 mm × 15 0.254 mm. primary radiator proposed coplanar waveguide-fed monopole comprised rectangular-shaped structure initially modified using slot, its bandwidth further ...