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Biometrics and soft biometrics characteristics are of greatimportance in forensics applications for identifying criminalsand law enforcement. Developing new biometrics andsoft biometrics are therefore of interest of many applications,among them forensics. Heartbeat signals have beenpreviously used as biometrics, but they have been measuredusing contact-based sensors. This paper extracts heartbeatsignals, using a contact-free method by a simple webcam.The extracted signals in this case are not as precise as thosethat can be extracted using contact-based sensors. However,the contact-free extracted heartbeat signals are shown in thispaper to have some potentials to be used as soft biometrics.Promising experimental results on a public database, haveshown that utilizing these signals can improve the accuracyof spoofing detection in a face recognition system.

This work presents a new Ultra Wide Band (UWB) beamforming fifth-order derivative Gaussian pulse transmitter with dual small Vivaldi antennas for remote acquisition of vital signals in impulse radar applications. The system consists of a programmable delay circuit (PDC or τ), a UWB pulse generator (PG) circuit and an array of two Vivaldi planar antennas. The circuits is designed using the 0.18µm CMOS IBM process. Spice simulations show the pulse generation with 90mVpp amplitude and 300ps width. The average power consumption is 120µW per pulse, using a 2V power supply at a pulse repetition rate (PRR) of 100MHz. Full tridimensional electromagnetic simulations, using CST MWS, show the main lobe radiation with a gain of 5.5dB, and a beam steering between 20º and -17.5º for azimuthal (θ) angles at the center frequency of 7.5GHz.