Abstract-In this paper, a novel and compact dual-band filter with enhanced upper stop characteristics has been presented. Dual band pass filter characteristics are achieved by introducing transmission zero (TZ) in pass band of band pass filter (BPF). The wide band pass filter (BPF) is implemented by combining low pass filter characteristics (i.e., stepped impedance resonator) and high pass filter characteristics (i.e., short stubs). Closed rectangular ring resonator (CRRR) and open loop rectangular ring (OLRR) combination is used to produce two transmission zeros (TZs). One TZ is placed on the pass band of BPF such that resultant filter characteristic consists of two pass band. However, the second TZ is placed at edge of the pass band in BPF to improve skirt selectivity. The two pass bands are designed to cover two popular wireless bands namely WiMAX (center frequency f 1 (3.5 GHz) and WLAN (center frequency f 2 (5.7 GHz)) bands, i.e., 3.35-3.65 GHz and 5.5-5.85 GHz respectively. Equi-ripple low pass stepped impedance resonator (SIR) filter response is responsible for improved and spurious free upper stop band (> 20 GHz, i.e., > 6f 1 ) and also provides sharp skirt attenuation at upper stop band. The proposed filter is implemented on an RT/Duroid 5880 (ε r = 2.2) substrate with thickness of 0.785 mm and surface area of 19 × 12 sq · mm. Good agreement between simulated and measured results ensures that the proposed filter is a suitable candidate for modern dual band communications.

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With the headway of the advanced image handling software and altering tools, a computerized picture can be effectively controlled. The identification of image manipulation is vital in light of the fact that an image can be utilized as legitimate confirmation, in crime scene investigation, and in numerous different fields. The image forgery detection techniques intend to confirm the credibility of computerized pictures with no prior information about the original image. There are numerous routes for altering a picture, for example, resampling, splicing, and copymove. In this paper, we have examined different type of image forgery and their detection techniques; mainly we focused on pixel based image forgery detection techniques.

A novel, compact band pass, UWB (Ultra Wide Band) filter has been designed. Equi-ripple stepped impedance resonator (SIR) for low pass filter (LPF) response is implemented to improve upper stop band characteristics. Three shorted unsymmetrical rectangular ring resonator (SURRR) is implemented to improve the high pass response that in turn improve the lower stop band characteristics of the proposed UWB filter. SIR (LPF) and SURRR (HPF) together produce good out of band characteristics for the UWB filter with low insertion loss. In addition transmission zero (TZ) is placed to improve the sharp skirt (roll-off) at upper stop band. The TZ are implemented by two quarter wavelength stubs. Finally, proposed filter is fabricated (dielectric constant r =2.2 and thickness=0.787 mm) and measured to validate the predicted results. The group delay of the filter is relatively constant and less than 0.25 ns over the operating pass band.