A compact ultra wideband bandpass filter (BPF) with sharp rejection and wide upper stopband is proposed in this letter. The proposed bandpass filter is constructed using modified U-shaped multimode resonator (MMR). The U-shaped MMR is loaded with two open stubs on the symmetrical locations. This proposed resonator has five resonant modes, out of which two are odd modes and the remaining are even modes. These modes are present in the UWB band and are used to realize the wideband passband of the filter. By optimizing the dimensions of the stubs, the five resonant modes of the resonator can be brought into the desired passband. This bandpass filter with fractional bandwidth better than 110% is simulated, fabricated, and measured. The measured impedance bandwidth of filter is from 3.75 to 13.75 GHz with an insertion loss of 2 dB and return loss better than 11 dB. The simulated and measured results show a good agreement. The group delay variation is less than 0.25 ns. A wide stopband bandwidth with 16 dB attenuation is up to 19 GHz is obtained in the proposed filter.

A sensor network is a system that consists of thousands of very small stations called sensor nodes. The communication among nodes is done in a wireless fashion, and thus, the name of wireless sensor networks. Wireless sensor networks (WSN) have generated tremendous interest among researchers in recent years because of their potential usage in wide variety of applications [1]. In mobile sensor network (MSN), nodes are free to move with wireless links without any infrastructure.This paper investigates & undertakes simulation based study of Adhoc Routing Protocols in wireless sensor Network. In this paper comparison of four Routing Protocols AODV, DYMO, OLSR & IERP is done by using random waypoint mobility model and changing the nodes mobility using QualNet 5.0.2 Simulator. The metrics used for performance evaluation are Average Jitter, Throughput, Endto End delay, Signals

A compact wide-band pass filter (BPF) with sharp band rejection characteristics and wide upper stopband is presented in this article. The proposed bandpass filter is designed using a fish spear-shaped multimode resonator (MMR). This fish spear-shaped MMR has four arms and have five resonant modes, out of which three are even modes and the remaining two modes are odd. These modes lie in the wide frequency spectrum and they are used to realize the wideband passband of the filter. These five modes are brought closer by optimizing the dimensions of fish spear-shaped MMR to get the desired passband. To improve out-of band performance, a stepped impedance resonator is added at the central plane. The proposed wideband BPF filter have fractional bandwidth better than 85%. Moreover, to verify the proposed concept the designed filter is fabricated and measured. The measured bandwidth of proposed filter is 6.82 GHz and is from 2.55 to 9.37 GHz with an insertion loss of 2 dB. The measured return loss of the filter is better than 10 dB in the entire designed wideband. Measured results are validated with the simulated results. The group delay variation is less than 0.25 ns. A wide stopband with 15 dB attenuation is extended up to 20 GHz is obtained.

In this paper, a novel two-stage fish spear-shaped multimode resonator (MMR)-based ultra wideband (UWB) bandpass filter (BPF) is presented. The fish spear-shaped MMR is loaded with stepped impedance resonator in order to improve the out-of-band performance of the proposed filter. The proposed UWB BPF filter has fractional bandwidth better than 110%. In order to validate the present design approach, the filter is fabricated on RT/Duroid 5880 having dielectric constant 2.2, thickness 0.787 mm and loss tangent of 0.0009. The measured passband bandwidth of the filter is from 3.3 to 11.85 GHz, with insertion loss of 1.5 dB and return loss better than 12 dB in the passband. The proposed filter has sharp selectivity and upper stopband with 20 dB attenuation from 12 to 24 GHz.

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