Advanced Materials Research Vols. 1049-1050

Abstract: Min-Max localization algorithm is usually used to acquire the position of a sensor node in wireless sensor networks by the reason of its simpleness and low complexity. However, Min-Max algorithm provides a coarse position estimation. In order to increase its accuracy, an Extended Min-Max (E-Min-Max) algorithm has been proposed. In this paper we focus on this algorithm and propose an improved E-Min-Max algorithm to enhance its accuracy further. Simulations show that the improved E-Min-Max algorithm outperforms its original version in localization.

Abstract: This system based on embedded technology, MMS wireless communication, etc. Various kinds of modern technology, design a kind of based on GPRS MMS remote monitoring alarm system, this system chooses LPC2132 chip as embedded processor, serial ports, camera, GPRS and infrared pyroelectric sensor module and other hardware. Main funtions as follows: when someone illegally broken into specific space abnormal happens, infrared pyroelectric sensor embedded processor immediately trigger caused disruption, the camera automatically shooting scene image, and transferred to the embedded processor module, embedded processor calls AT instructions through GPRS networks will the collected pictures sent to specify users mobile phone. Users can call or send messages to the system for pictures, but also through the mobile terminal control the system protection and removal. System software embedded in part using development platform ADS development, the key technology was embedded processor interrupt trigger, user instruction processing, control the acquisition and sending MMS etc. This paper analyses the working principle, AT GPRS directive system structure of use, embedded in space, thus realize user of real-time monitoring and alarm.

Abstract: Proposed of a model of microstrip balun based on metamaterial ,it uses the unique aspect of negative dielectric constant and negative magnetic permeability of metamaterial in the microwave , and designs the dielectric substrate , based on which we constructed a microstrip balun which can translate unbalanced 50 ohm signal to 120 ohm balanced .Simulation results show that it can perform well at reducing the size of balun , at the return loss (s11) ,insertion loss (s21) from 2G to 6G. As well as it can effectively meet the two-ports phase difference about 180 degrees.