The paper considers possibilities for processing of UWB signals of irregular lines in which heterogeneity were connected in parallel. It finds the elements of the scattering matrix of the parallel loop, loaded a reactive load. The special cases are discussed when the loads of the parallel loop are short circuit and idling. Expressions for the frequency and time domains: the frequency characteristics and transient characteristics are obtained. It is shown that the transmitted and reflected waves are determined by the superposition of two waves: primary reflected wave from the loop and the wave reflected from its end. This enables the UWB signal to be formed on such structure. The paper considers the case when the parallel loop is an irregular line. Scattering matrix elements of such unit are founded for the short-circuit and idling at the end of the line, as well as for traveling-wave regime. The examples of various parallel structures are considered. It is concluded that such structures have the prospects for use in forming and filtering ultrawideband signals due to the appearing possibility for separation of the incident and transmitted waves.