The proliferation of Radio Controlled Improvised Explosive Devices (RC-IED) is a growing threat around the world. The ease of construction and low cost of these devices are transforming common things in lethal tramps. The fight against this threats normally involves the use of sophisticated and expensive equipment of Electronic Warfare based on high speed DSP systems, just to detect the presence of detonation signals. In this work is showed how to find activation signals based on the characteristic of the power in a specific band and the previous knowledge about the detonation signals. As proof of concept we have taken the information about the RC-IEDs used in the Colombian conflict and develop an algorithm to find detonation signals based on the measured power in frequencies between 136 MHz and 174 MHz (2 meter civil band)
A low-cost acoustic localization system is presented, in which a video camera is directed towards the source of impulsive sounds such as gunshots. An analog filter is implemented at the first stage, in order to reduce the range of frequencies to analyze, hence narrowing and improving the localization of gunshots. The system is design for the integration of open source consumer electronics and processing devices, which makes large-scale deployment possible even in developing countries. Furthermore, results are also obtained with a prototype that shows a high percentage of successes.
This work presents a prototype of low-cost gunshots identification system that uses consumer electronics in order to ensure the existence of gunshots and then classify it according to a previously established database. The implementation of this tool in the urban areas is to set records that support the forensics, hence improving law enforcement also on developing countries. An analysis of its effectiveness is presented in comparison with theoretical results obtained with numerical simulations.
A characterization study is made from a trilateration system for impulsive sounds, in which theoretical analysis and experimental results are presented. This system uses an analog trilateration method, avoiding to implement high frequency ADC conversion elements. It also presents the optimization of the chosen array of microphones, thus allowing for a better trilateration algorithm behavior.
This paper presents computational models of microstrip antennas using the software CST. The main objective of this paper is to evaluate an alternative way to miniaturize dimensions of microstrip antennas. In order to this, a coating made of ceramic with high dielectric constant was considered for two different cases. Scattering parameters (S<sub>11</sub>) and radiation patterns were obtained for both structures and compared with standard microstrip antennas for S and C bands. Finally, the results show the possibility of reducing the dimensions by 22% to 31% and demonstrate the feasibility for the implementation and development of these antennas.
This paper shows simulations of an all-fiber fast optical code division multiple access communications system (OCDMA), using strong apodized fiber Bragg gratings (FBGs) arrays as passive encoding-decoding devices. Auto and cross-correlation functions of the user signals, and bit error rate (BER) were used as evaluation criteria. Through numerical analysis, we demonstrated that when strong Bragg gratings are used the performance of the system is increased. We obtain the BER performance for strong gratings and compare results in various cases.