Since 2014, Japan has aggressively moved toward modernizing its energy infrastructure. Smart meters are an important part of this policy, bringing more advanced features than their predecessors, including the ability to communicate in real-time with utilities and provide more detailed information to consumers about their energy usage. Wireless Smart Ubiquitous Network (Wi-SUN) with its low power consumption, long-range communication capabilities, and secure networking protocols, has become a key enabler for smart city deployments in Japan. The Wi-SUN Alliance, a global non-profit organization that promotes the interoperability and deployment of Wi-SUN technology, has a strong presence in Japan, with many Japanese companies actively participating in the development and deployment of Wi-SUN solutions.
Nagano Japan Radio Co., Ltd., through its innovative technologies in renewable energy, energy storage, and smart grid systems, has played a significant role in this modernization. Part of the company’s mission is to equip original equipment manufacturers (ODM/OEMs), including those developing the next generation of smart meters and other IoT devices. It was with this in mind that the company set out to create a module that could deliver on performance requirements while creating a positive user experience for developers as well as end customers.
To provide manufacturers of next-generation smart meters with new functionality and performance improvements that support Japan’s ambitious efforts to improve energy efficiency by replacing 80 percent of the country’s conventional meters by 2024.
Nagano Japan Radio Co., Ltd. utilizes the Silicon Labs FG25 sub-GHz SoC, which supports OFDM modulations introduced in Wi-SUN Field Area Network (FAN) 1.1, to develop modules that can meet the demands of these next-gen smart meters.
The combination MCU/transceiver package of the FG25 helps Nagano Japan Radio Co., Ltd. deliver on the cost, size, and performance requirements of its customers, and continues to build on the decade-long partnership between the two companies.
FG25 Sub-GHz SoC for Long-Range, Mission-Critical Projects
To satisfy the requirements of Japan’s smart metering policies, as well as other market-adjacent connected devices like solar panels and EV chargers, Nagano Japan Radio Co., Ltd. had some very clear objectives. First, as mentioned above, Wi-SUN functionality was critical. Wi-SUN has a long-range communication capability, which allows it to cover a wide area with fewer nodes. This is especially useful for smart metering, where a large number of meters need to be connected to a central system over a wide area. Wi-SUN uses a mesh network topology, which means that if one node fails, the network can automatically reconfigure itself to maintain connectivity. Wi-SUN certification, coupled with performance, security, and ease were a few of the reasons the FG25 sub-GHz SoC emerged as the preferred basis for the Nagano Japan Radio Co., Ltd.'s Wi-SUN module. Finally, Wi-SUN is an open standard that allows devices from different vendors to communicate with each other seamlessly. This is important for smart metering applications, where meters from different manufacturers may be used in the same system.
Wi-SUN certification, coupled with performance, security, and ease were a few of the reasons the FG25 sub-GHz SoC emerged as the preferred basis for Nagano Japan Radio Co., Ltd.'s Wi-SUN module.
Orthogonal Frequency Division Multiplexing (OFDM) and Smart Metering
Another key feature of the FG25 is Orthogonal Frequency Division Multiplexing, or OFDM. This is a digital modulation technique well-suited for smart metering because it can transmit large amounts of data over a limited bandwidth. In smart metering applications, this allows for more frequent and accurate data collection, which in turn leads to better energy management. OFDM is also power efficient, which makes it possible for battery-operated smart meters to transmit data at low power levels while not sacrificing signal quality. Part of Japan’s approach to the development of these second-generation smart meters is compatibility with Wi-SUN FAN 1.1, specifically due to the OFDM capability. The FG25 is the first SoC in Silicon Labs’ portfolio to support OFDM. With the higher data rates, the FG25 SoC enables the large networks needed by smart cities where the nodes can number in the thousands.