in some mobile systems, intelligent antennas are used to increase efficiency in a wide frequency band and different environmental and electromagnetic conditions. environmental factors, such as position of nearby objects, antenna mobility and even user type, can vary the antenna input impedance appreciably. therefore, it is necessary to incorporate an adaptive impedance matching circuit between ...

Using composite right-left handed (CRLH) transmission line concept, a novel miniaturized dual notch band filter (DNBF) is proposed. The suggested DNBF consists of an interdigital transmission line (ITL), split ring resonators (SRRs) and complementary split ring resonators (CSRRs). Since the resonance frequency of the SRRs and CSRRs are quite independent of each other, the dual notch bands of th...

Multi-band approach has recently been introduced for recognition of speech corrupted by frequency-localized noise, showing higher robustness than the traditional full-band approach. However, the multi-band approach has been found to be less robust for wide-band noise than the full-band approach. In this paper, we present a multi-band recognition system based on the combination of the probabilis...

This paper presents a low loss and high selective lowpass filter which is implemented using suspended stripline (SSL) technology. The proposed structure is comprised of a 13th order generalized Chebyshev lowpass filter which enjoys integrated waveguide-to-SSL transitions. This filter is designed and fabricated to be used as lowpass channel of a U-band diplexer employed in frontend of a U-band d...