Study Of Smart Sensor System Based On Low-Power Processors

In recent years, as computer technology and network communication technologies, the rapid development of intelligent sensor system as an emerging, vigorous development of embedded systems has been widely used in various areas of human life. Intelligent sensor system is toward the ultra-low power, multi-data fusion, micro-oriented direction. It is for improving the quality of life of modern humans to create a comfortable, safe and convenient living space has a very important significance.This article first introduces the concept of smart sensor systems, research directions and research situation,then proposed based on low-power processors used in smart sensor system design. Most common smart sensor systems are composed of smart sensor terminals and control servers, using wired communications and control servers and with the computer as a host. Such a structure will cause high power, limited applications and against for use. With low-power as main line, this paper made preliminary studies of lots of technologies in the field of smart sensor. Recommendations of system architecture were made to divide control servers into low-power wireless smart monitors and user management system. The entire low-power smart sensor system consists of a low-power smart sensor end, low-power wireless smart monitors and user management systems, whose functions between them are independent . Low-power smart sensor terminals and low-power wireless smart monitors transmitted data via wireless, while user management systems used RS-232 cable communications to manage low-power smart sensor terminals and low-power wireless smart monitors, which reduces power consumption and increases flexibility and reliability.In the low-power smart sensor communication field, there are a variety of wireless communication technologies such as ZigBee, Bluetooth, Wi-Fi technology, ultra-wideband technology (UWB) and so on. Low-power smart sensor networks possess technical characteristics of low-power, low-rate, short-range communications. Wi-Fi technology mainly applied to high-speed data transmission of short distance and medium power, while Bluetooth technology mainly applied to medium-speed transmission of low-power and short distance. The ZigBee technology is a perfect interpretation of network features of low-power smart sensor system. With the low-power embedded technology continues to progress, embedded microprocessors is toward the low power consumption, miniaturization, high integration direction. Through the low-power smart sensor systems analysis, this paper uses ultra-low-power microprocessor MSP430F2132, MSP430F2168, respectively, as the core processor of low-power smart sensor terminals and low-power wireless smart monitors. MSP430 series ultra-low-power microprocessor is ultra-low-power, high-performance 16-bit embedded processor introduced by TI, whose chip integrates eternal installment as the preferred low-power embedded systems. The choice of ZigBee wireless network technology and MSP430 series ultra-low-power microprocessor lay the foundation for the subsequent design.With the continuous progress of human society, human ability to explore the natural grows, the shadow of the sensor left from the hot equator to the cold Arctic; from high peaks to the deep seabed. However, features of conventional sensors ,such as single function, instable performance, poor adaptability, has been unable to meet human needs; and features of common smart sensor terminal, such as high low, large energy, wired communications, are against for smart sensors to work long, which limits the application of smart sensor system. Therefore, this article has designed a low-power smart sensor terminal. The terminal uses ultra-low-power embedded technology, the slope of A / D measurement technology, power switching technology. Among them, slope A / D measurement technology brings a broad prospect for smart sensor system, by which temperature smart sensor end-points can become moisture smart sensor end-points through replacement of sensors and internal firmware without redesigning hardware. Power switching technology enables information data stored in smart sensor terminals more safe and reliable.Traditional control servers use computers as host monitoring system, which is high cost, complex configuration and high power. With the emergence of low-power embedded technologies and wireless networking, infinite vitality has been brought for computer smart monitoring system. This paper selected TI's ultra-low-power microprocessor MSP430F2168 and CC2520 low-power wireless module to have designed low-power wireless smart monitor. This monitoring device possesses characteristics of low power, no duty, regular collection of smart sensor terminal data, alarm of power shortage, alarm of temperature beyond the threshold and so on. The selection of low-power microprocessors of low-power wireless smart monitors can reduce power of entire sensor system and simplify system configuration significantly.Taking into account that a complete smart sensor system should have multi-functions configuration and friendly interface, this paper made a detailed analysis of Bootstrap Protocol, designed and implemented user management system based on the Bootstrap Protocol. The management system can be installed on the computer of Windows operating system and made communication with low-power smart sensor terminals and low-power wireless smart monitor through RS-232 interface. Bootstrap protocol is specifically for TI's MSP430 series microprocessors. Into the Bootstrap Protocol. Entering Bootstrap Protocol, there is a need for TEST and RTS pin of MSP430 to produce special time sequence, which is called the Bootstrap Loader state (BSL mode). The major features of user management system based on Bootstrap Protocol include software updates, regular reading sensor information of low-power wireless smart monitor, log auditing of low-power smart sensor and low-power wireless monitoring device.In this paper, smart sensor systems based on low-power processors are composed of low-power smart sensor terminals, low-power wireless smart monitors and user management system based on Bootstrap Protocol. The feasibility of the program is tested by power and high/low temperature experiment.Through this research, so that the author's smart sensor systems have a preliminary understanding of, but this is only an smart sensor system research. As a converged multi-technology for embedded applications, there are a lot of technology needs to study, to explore.