Admissibility of a Video As Evidence in a Court: its Presentation and Probative Value

To general public, all videos are perceived to be true, but they may not have probative value in the Court of law. The undertaken article analyzes the admissibility and probative value of a video presented as evidence before a court in the Criminal Justice System of Pakistan (CJSP). It analyzes the relevant law and diagnoses the problems with the video evidence through the lens of the judgments of Superior Courts. The court of law objectively ascertains that a video presented as evidentiary means bears significant relevance to the fact in question. It must be admissible under the law, and it must be proved to be genuine. To fill up the gap between a “Video” and a “Video Evidence”, there is a process, which is known as video authentication. It determines that the video contents are genuine, authentic, credible, unaltered, untampered and unfabricated. The study discusses various modes of video authentication. Precedents set by superior courts of Pakistan show that convictions have been made once the courts are satisfied with the credibility of video evidence. In the court of law, video evidence is normally presented after the completion of prosecution evidence. The video is played in court and is watched by the presence. But the researcher establishes that such process does not have legal justification. The article suggests that it would be legal and proper for the prosecution to produce the video evidence through the witness, during his evidence, who is either victim, witness, recorded and/or copied the video directly from original source such as C.C.T.V system and that witness would be subjected to cross examination.

Design and Characterization of Reconfigurable Antennas for Ultra Wideband Uwb Application

This research work focuses on design and characterization of a compact reconfigurable band notch UWB-MIMO Antenna. The analysis of two different designs of UWB antenna elements is presented in this thesis. The reconfigurable performance of these antenna elements is analyzed for 2 × 2 and 4 × 4 MIMO scenarios as well. In first design a miniaturized antenna element exhibiting reconfigurable notched band functionality is presented for UWB-MIMO applications. The antenna element consists of rectangular lower half, fed by a rectangular feed line. Antenna elements shows a good impedance match over frequency band of 3.1 GHz - 10.6 GHz. To achieve enhanced isolation in MIMO communication, a slotted circular shaped decoupling structure is designed on the ground plane. Decoupling structure provides isolation above 20 dB for radiating elements operating in ultra wideband. Electronically reconfigurable bandnotch characteristic at WLAN (5.15 - 5.825 GHz) is achieved by inserting PIN diodes in inverted L-shaped slots present in the main radiating elements. In second design MIMO antenna element exhibiting electronically reconfigurable WiMAX (3.2 - 3.8 GHz) band notch capability is proposed for ultra wideband MIMO applications. Isolation of more than 25 dB among all radiating elements over entire ultra wideband is achieved using rectangular slotted decoupling structure. Finite Element Method (FEM) based simulations have been carried out in Ansys High Frequency Structural Simulator (HFSS)™ for the design and optimization of antenna. The equivalent circuit analysis of proposed designs is performed in Advanced Design System (ADS) software and for Characteristic Mode Analysis (CMA), CST Studio Suite® is used. Characteristic Mode Analysis (CMA) of UWB band notch antennas explains the availability of resonant modes linked to the surrounded narrowband slot structure (notch modes). The proper placement and location of slot within the geometry of the UWB antenna determines the effect over the rest of the radiating modes of the wideband structure, and consequently, over the behavior of the antenna. Elements are fabricated and tested on FR-4 laminates of thickness 0.8 mm and 1.6 mm. The diversity parameters for all MIMO design configurations are well within desired limits. Moreover, simulated results are verified through measurements. S-parameters are measured using vector network analyzer (VNA), while radiation patterns are measured in anechoic chamber. The measured results are in good agreement with the simulated results.