Provided is a reflection-type bandpass filter for ultra-wideband wireless data communication, including a substrate. The substrate includes a dielectric layer and a ground layer deposited on one surface of the dielectric layer, a center conductor provided on a surface of the dielectric layer opposite the ground layer, and a side conductor provided on the surface of the dielectric layer opposite the ground layer. There is a prescribed distance between conductors with a non-conducting portion intervening therebetween. A center conductor width or a distance between conductors, or both, are distributed non-uniformly along a length direction of the center conductor.