Abstract: As technological advancement in recent years is bringing ease to our everyday life, smart home systems based on wireless networks and sensors are rapidly gaining importance. Research on microcontroller controller smart home systems has become popular due to its low cost and reliability. However, appliance switching capacity of microcontroller is quite low which limits the widespread use of such sort of systems. This paper introduces an external appliance switching circuit for microcontroller controller automated home which has the ability to control 208 appliances. This large appliance switching capability has been obtained by demultiplexing digital signals obtained from microcontroller board using a complex array of 4 to 16 line decoders. The proposed appliance switching circuit can be implemented with 60-70% less wiring cost in real time compared to the typical wiring technique in microcontroller controlled smart homes. Also, hardware implementation expenditure in this research has been reduced significantly compared to the existing designs. Moreover, the issue associated with existing microcontroller appliance switching scheme in case of incorporating manual switch has been solved. The proposed circuit is incorporated with a smart phone application by which the user sends commands to the microcontroller board using Bluetooth as the medium of wireless transfer. The proposed microcontroller controlled smart home system with external appliance switching circuit is quite cheaper than the existing systems which allows consumers to afford smart living with limited budget. Due to reduction of implementation cost and solution of major technical design issues incorporated with the existing microcontroller-based system been solved in this research work, microcontroller based smart home systems is expected to become a potential product in the market in near future.Abstract: As technological advancement in recent years is bringing ease to our everyday life, smart home systems based on wireless networks and sensors are rapidly gaining importance. Research on microcontroller controller smart home systems has become popular due to its low cost and reliability. However, appliance switching capacity of microcontroller is qu...Show More
Abstract: In some large scenic spots, such as seashore tourists, there may be accidents such as loss. In addition, in order to facilitate the management and monitoring of tourists, the project designed a system for seashore tourists positioning. Firstly, this paper introduces the overall design scheme of the system, in which the positioning tag uses MC13224 chip as the main processor, transmits GPS information to the positioning gateway through ZigBee communication mode, and receives information from the server side. Then, the hardware design block diagram and software design flow of the gateway and the base station are analyzed respectively. The validation shows that the location tag can send the location information to the server and receive the information from the server. It realizes that tourists can receive the information from the server. The client can monitor the location of tourists and alarm information. Finally, the application value of the system is analyzed.Abstract: In some large scenic spots, such as seashore tourists, there may be accidents such as loss. In addition, in order to facilitate the management and monitoring of tourists, the project designed a system for seashore tourists positioning. Firstly, this paper introduces the overall design scheme of the system, in which the positioning tag uses MC13224 ...Show More
Abstract: Traditional Hybrid Multilevel inverter produces (2n+1) levels at output voltage of inverter for n number of sources by a switching mechanism which requires 4n number of switches. However, one underlying problem of single phase multilevel inverter is that it requires isolated sources which render it inappropriate except where isolated energy sources are available. In this paper, firstly, a new technique is proposed for generating multiple isolated Buck-Boost DC sources of variable voltages from a single DC source. Secondly, a new switching algorithm is proposed by which number of output voltage levels can be increased by 80%, 157% and 833% while reducing number of switch count by 0%, 16.66% and 25% keeping voltage stress across the switches unhampered for two, three and four source inverter respectively compared to traditional multilevel inverter. As a result, conspicuous improvement is achieved in terms of harmonic distortion dropping it down to 4% and less than 1% for three and four source inverter respectively even without using output filters or sinusoidal PWM switching signals. A meticulous analysis of the circuit configuration and switching algorithm along with detailed performance analysis is provided throughout the paper.Abstract: Traditional Hybrid Multilevel inverter produces (2n+1) levels at output voltage of inverter for n number of sources by a switching mechanism which requires 4n number of switches. However, one underlying problem of single phase multilevel inverter is that it requires isolated sources which render it inappropriate except where isolated energy sources...Show More