The development and application of sensor network technology have made significant progress. This is particularly evident in markets such as home automation, industrial automation, building control, smart metering, and power management. At the same time, the standardization work for wireless sensors has progressed rapidly, greatly reducing the complexity of smart sensors and wireless sensor networks. The total number of patents issued in the United States continues to increase year by year, with the number of patents issued in 2009 being more than twice that of 2005, indicating that research and development activities in wireless sensor network technology have been very strong in recent years.
The third wave of the information revolution is quietly approaching and will ultimately change the way society, businesses, communities, and individuals live. This information revolution is the much-discussed Internet of Things (IoT), as well as the latest version of the new generation of the Internet and ubiquitous computing models. To enable the Internet of Things to achieve global interconnectivity and the ability to communicate with anyone and anything at any time and place, it involves a very broad range of information industry technologies. Among these, wireless sensor network (WSN) technology has received significant attention.
Wireless sensor networks are generally composed of spatially distributed and independent network nodes. The nodes contain sensors to monitor physical or environmental conditions such as temperature, sound, vibration, pressure, motion, or pollutants. Each node typically has a radio transceiver or other wireless communication device to transmit sensing data to databases and other users through the network. In this way, wireless sensor networks can be used for data collection (DataCollection), target tracking (Objecttracking), and alarm monitoring (Alarmmonitoring), among others.
In recent years, the development and application of wireless sensor network technology both domestically and internationally have made significant progress. This is particularly evident in markets such as home automation, industrial automation, building control, smart metering, and power management. At the same time, the standardization work for wireless sensor networks has progressed rapidly, greatly reducing the complexity of smart sensors and wireless sensor networks. For example, the IEEE 1451 Working Group has established a plug-and-play standard for smart sensors, allowing all compliant sensors to work with other instruments and systems.
This series of standards is known as the IEEE 1451 smart sensor (including sensors and actuators) interface standards, which define different standards for connecting sensors to microprocessors, instrumentation systems, and remote network control. Among these standards, part IEEE 1451.5 is currently the focus of many R&D activities. Part IEEE 1451.5 specifies the technology that enables wireless communication between sensors and other devices compatible with 1451.
The IEEE is also developing two standards for wireless personal area networks (WPAN), namely IEEE 802.11 and IEEE 802.15. Among them, the IEEE 802.15.4 standard is gradually being accepted as the standard for low-rate wireless personal area networks (LR-WPANs) physical layer and media access control. In addition, there are two industrial standards based on IEEE 802.15.4 in the field of wireless sensor networks: ZigBee and WirelessHART. ZigBee is a wireless technology developed as an open global standard to address the special needs of low-cost, low-power wireless sensor networks. This standard fully utilizes the physical layer specifications of the IEEE 802.15.4 radio transceiver and operates in globally available frequency ranges without special licensing: 2.400–2.484 GHz, 902–928 MHz, and 868.0–868.6 MHz; WirelessHART is another open standard wireless network technology developed by the HART Communication Foundation. This protocol employs time synchronization, self-organization, and self-healing mesh network structures. The protocol currently supports operation using radio media based on the IEEE 802.15.4 standard in the 2.4 GHz ISM band.
Additionally, other industry standards and proprietary systems may also serve as options for implementing wireless sensor network technology. For example, EnOcean is a widely used wireless communication system in the field of building automation, which is also considered a potential technology for wireless sensor networks, although it has not been standardized by any recognized standardization body. Z-Wave is a proprietary standard for wireless communication designed for home automation, specifically targeting remote control applications in home and light commercial environments. This technology embeds low-power wireless transceivers into or onto home electronic devices and systems, such as lighting systems, home access control systems, entertainment systems, and appliances. This technology has been standardized by the Z-Wave Alliance, an international consortium of manufacturers responsible for coordinating the compatibility of Z-Wave products and devices.
At the same time, some existing standards are also being modified to accommodate wireless sensor network technology. For example, the wireless local area network (WLAN) standard based on IEEE 802.11, known as WiFi, has incorporated a version that supports low power—so-called low-power WiFi—for implementing wireless sensor network technology.
Data from the U.S. Patent Office shows that the United States holds the most authorized patents in wireless sensor network technology, followed by Japan, with Canada, South Korea, and France following. At the same time, the U.S. also has the most published patent applications, with South Korea following, and then Japan, Sweden, and Taiwan. The total number of patents issued in the United States continues to increase year by year, with the number of patents issued in 2009 being more than twice that of 2005, indicating that research and development activities in wireless sensor network technology have been very strong in recent years.
If we analyze the distribution of U.S. patents by company, the top 15 leading companies in wireless sensor network technology are: Cisco, Ericsson, Fisher-Rosemount, General Electric (GE), Honeywell, IBM, Intel, Microsoft, Motorola, NEC, Nokia, Philips, Samsung, Siemens, and Sony. Among them, Nokia holds the most authorized U.S. patents, followed closely by Motorola, Intel, and Microsoft; Samsung has the most published U.S. patent applications, followed by Honeywell, Microsoft, Motorola, and NEC. Additionally, it is noteworthy that IBM is currently one of the leading companies in the Internet of Things.
