Miniaturization of nonuniform transmission lines for ultra-wideband pulse shaping

This paper presents the miniaturization of non uniform transmission lines (NUTL) for ultra-wide band (UWB) applications using various substrate materials. NUTLs are designed with four different substrates. An example of NUTL designed for an impulse response depicting a modified Hermite polynomial pulse with band width exceeding 10GHz and duration of 1 ns. This work is a step towards the miniaturization of NUTL. It is found that the length of the NUTL designed with TLX 8 is 190 mm and CER 10 is 98 mm, this means the overall length of NUTL can be reduced to 50 % using high permittivity substrates. Simulation and measurement results of NUTLs with different substrate materials are included.