Considering Home Wireless Connected Lighting ?

You want to control your lights wirelessly. How do you know which wireless technology to use?  In this article, Silicon Labs will provide insight into home wireless connected lighting.  Trends in wireless technologies, protocols, and a home connected lighting application is presented.

 Home Wireless Connected Lighting Market

According to research firm IHS Markit, the residential smart lighting market was valued at $1B in 2015. IHS projects the market to expand at a 30% compound annual growth rate from current 2015 to 2020 globally. 

Connected lighting and home automation presents challenges to early adopters and innovative entrepreneurs. Market makers must design simple, flexible, reliable lighting control solutions that feature security, future proof updates, and an ecosystem with device interoperability. Designers want to know which wireless protocols are best suited for wireless connected lighting. 

 Wireless Protocols for Connected Lighting Control

Wi-Fi connectivity is ideal for high data rate products and services in the connected home, and for providing connectivity to the Internet cloud via home gateways. However, Wi-Fi is not suited for lighting networks due to Wi-Fi’s large protocol stack, memory and processor power requirements, and its star network topology. 

Several different wireless technologies, shown in Figure 1, are available in this market to address elements of wireless lighting control. Wi-Fi, Bluetooth, ZigBee and Thread for mesh networking, and proprietary sub-GHz protocols, address lighting control needs. Mesh networks provide a communications backbone that allows a wide variety of connected wireless devices, such as Smart LED lights, switches, thermostats and sensors.

 Figure 1.  Wireless Protocols

Bluetooth enabled devices in a connected home provide direct connectivity to smartphones applications providing device control without the power consumption of Wi-Fi, However, Bluetooth/BLE has a limited network device count, lacks scalability and the benefits of a mesh network. 

ZigBee networking technology is a local mesh network based on the 802.15.4 standard that is scalable to hundreds of devices. The ZigBee cluster library defines features of smart lights and home automation devices that provide control of Smart light of dimming, RGB color, and color temperature. The ZigBee mesh networking along with cluster libraries is ideal for lighting control. However, direct smartphone control isn’t supported. The ZigBee gateway router is required to serve as a bridge to connect ZigBee devices to a Wi-Fi or Ethernet IP-based LAN network enabling Internet control and cloud connectivity. 

Thread is an emerging mesh network technology that provides IPv6 networking protocol built on open standards for low-power 802.15.4 mesh networks that can securely connect hundreds of devices to each other and directly to the Internet Cloud. Thread 1.1 is emerging so only a small number of thread-based devices are available. Thread devices are able to run the ZigBee application layer which provides interoperability with the available ZigBee home control devices.  “A key strength of the ZigBee Alliance's technologies is our application layer — the only mature, widely deployed, interoperable and open IoT application language” said Tobin Richardson, President and CEO of the ZigBee Alliance. 

Finally, Proprietary protocols are used in closed ecosystems.  Multi-band radios may be used to provide sub-GHz bands instead of 2.4GHz, which can provide a longer range and improve propagation in homes.

 Multi-Protocol in Lighting Applications

The evolution of embedded wireless SoCs with multi-protocol stacks is becoming a differentiator to provide product upgradeability, better user experience, and enhanced use cases for connected lighting designs and home automation. A multi-protocol application for Bluetooth/BLE is for commissioning a device to join a network, which may be running both ZigBee or Thread and Bluetooth at the same time.

Switched Multi-Protocol in an implementation of a multi-protocol platform that provides the ability to change which wireless protocol is supported by bootloading a new firmware image while the device is deployed in the field. This requires some fundamental building blocks to be in place, but opens up opportunity for future proofing existing products.

There are two primary cases for switched multiprotocol; Future-Proofing and Commissioning.

 Future Proofing.  The IoT is an evolving market for device manufacturers. There are many wireless protocols available currently and under development.  It is difficult to determine which one will deploy, dominate, or become the defacto standard in their markets. A device manufacturer may plan to sell their device into different ecosystems or may plan for an ecosystem change over time. A light bulb manufacturer may ship Bluetooth enabled light bulbs so that consumers can immediately directly control their lights from their smartphone via a supplied app. In the future, the consumer may purchase a home automation system that uses ZigBee or Thread or some proprietary protocol and may wish to add the light bulb into that ecosystem.  An ecosystem may deploy ZigBee networking today, but may switch to Thread protocol later when their application layer and IPv6 features are mature. The recent Bluetooth Mesh feature announced in Bluetooth 5.0 will offer a Mesh alternative to Zigbee and Thread. Implementing multi-protocol solutions will provide an upgrade path for future proofing.

Commissioning via Smartphone.  A device manufacturer will chose a wireless protocol for lighting control, however they may want to use a smartphone app to commission devices onto the network.  Implementing Smartphone control requires a Bluetooth commissioning application on the device; a commissioning application on a smartphone; and a Bluetooth application with network authentication on the Home Gateway. Using the smartphone app the user can authenticate the device to join the network, set up a pairing with other lighting or home automation devices in the network, then switch over to the ZigBee or Thread wireless stack that the network is running. Each wireless network will have its own mechanisms for joining and pairing devices, but all can be accommodated with this mechanism. 

In Figure 2, the smartphone uses a BLE connection to the wireless lightbulb to commission the device on the ZigBee or Thread network. The user operates the smartphone app to get the device joined onto the network, set up BLE pairing with other appropriate devices in the network, then switches over to ZigBee or Thread mesh network stack used by the lighting control network.  Figure 3 shows the initial load of the Bluetooth/BLE stack for commissioning, the bootloader execution 10 -15 seconds to load the mesh stack, and the protocol switch to Zig-Bee or Thread.

Figure 2.   Switched Protocol – BLE commissioning on mesh network    

Figure 3.  Switched Protocol – BLE commissioning time requirements                  

 Wireless SoC and Modules deliver multi-protocol performance

The system-on-chip implementation is the critical device to support wireless standards, ensuring interoperability among connected devices supporting these standards. The SoC device must have adequate flash memory to be able to store multiple protocol stacks in firmware and to enable dynamic switching among the protocols as devices join the network. Equally important is the application layer software that connects the end user to the hardware.  Leading SoC vendors are offering comprehensive hardware, protocol stacks, and software development tools to support the design of multi-protocol devices. This unified hardware and software approach to multiprotocol connectivity will ensure seamless interoperability of wireless lighting devices and sensors.

Silicon Labs is a supplier of smart, connected, energy-friendly 8 & 32-bit MCUs, wireless transceivers, wireless SoCs, and smart sensors. Take advantage of multiple wireless protocols including Zigbee®, Thread, and Bluetooth® with SoCs and certified wireless stacks from Silicon Labs.

• Our 32-bit EFR32 Gecko MCU portfolio includes nearly 250 products with ARM cores ranging from Cortex-M0+ to Cortex-M4, and integrated flash memory from 4KB to 1MB, supporting a broad spectrum of energy-sensitive, battery-powered applications.
• Our wireless portfolio includes IC products (from sub-GHz transceivers and transmitters to 2.4 GHz ARM-based ZigBee SoCs), software stacks and development tools.
• Our wireless protocols include Zigbee®, Thread, Bluetooth® with SoCs and certified wireless stacks from Silicon Labs.
• Silicon Labs’ MGM111 Mighty Gecko Module is a pre-certified module with a Might Gecko wireless SoC can save months of design and development effort featuring a 2.4 GHz radio with support for wireless mesh networking using the ZigBee or Thread protocols.  

Where to get more Info :

 Silicon Labs’ wireless offerings:  www.silabs.com/wireless.

Silicon Labs connected lighting:

http://www.silabs.com/solutions/home-automation-and-entertainment/connected-lighting

 EFR32™ Mighty Gecko Mesh Networking Wireless SoCs for ZigBee® and Thread

http://www.silabs.com/products/wireless/mesh-networking/efr32mg-mighty-gecko-zigbee-thread-soc

Silicon Labs’ Mighty Gecko family of SoCs is ideal for designing energy-friendly wireless connected IoT devices. Part of the Wireless Gecko portfolio, the Mighty Gecko is the superset part and supports 2.4 GHz and Sub-GHz protocols, including Zigbee, Thread, BLE, and Silicon Labs Connect stack for 2.4 GHz, as well as Sub-GHz for proprietary protocols and the Connect stack.

 MGM111 Mighty Gecko Module

http://www.silabs.com/products/wireless/mesh-networking/mighty-gecko-modules/mgm111-mightly-gecko-module

Silicon Labs’ MGM111 Mighty Gecko Module is a pre-certified module with a Mighty Gecko wireless SoC that saves months of design and development effort.  The MGM111 is based on the EFR32 Mighty Gecko SoC, a highly integrated, energy efficient device that includes an ARM Cortex-M4 with DSP extensions and an FPU, and a 2.4 GHz radio with support for wireless mesh networking using the ZigBee or Thread protocols for low-power wireless applications in the lighting, connected home, building automation.