The majority of alarm systems today are based on sub-1GHz RF technology. Due to the physical properties of sub-1GHz frequencies, it is possible to guarantee full house coverage in a star network topology. The star network topology enables power-efficient and low-cost networks with small microcontrollers (MCUs). The star network also makes the installation very easy. Networks requiring mesh or repeater functionality complicates the installation process, making it difficult for professional installers and DIY consumers. Mesh/repeater functionality also adds cost (MCU memory), power (bigger battery), and latency.
The smartphone has become an increasingly important way for people to communicate. The ability to use the smartphone to access, control, and monitor the house is a logical extension to the intruder alarm system. This cloud connection is typically built into the alarm panel, or as a standalone gateway extension. All IP traffic is typically handled in the gateway, to avoid any additional overhead in the highly optimized communication with the alarm sensors. This way the addition of cloud connectivity does not need to influence the protocol used for sensor communication, making it possible to use sensors that are low power and low cost.
The cloud connection opens up new possibilities and applications for the alarm system, including adding home automation features such as remote power switches. A switch can be used to control lights to mimic that the person is present, or to control HVAC systems. Since the infrastructure and user interface is already in place from the alarm system, the barrier of entry and added cost is low compared to a standalone home automation system.
Wireless sensors in an intruder alarm system have strong benefits both from a cost and end-user perspective. To assure a long battery lifetime and simple installation, sub-1GHz star networks are commonly used, which also deliver a robust and future-proof system as RF co-existence properties become increasingly important. Lastly, cloud connectivity and home automation extensions represent promising new opportunities for additional features and benefits. Essentially, all of this enables consumers to install their own cost-efficient and high-performing systems to monitor their homes anywhere, anytime, which is the ultimate security.
— Terje Lassen is industrial products line manager for Texas Instruments Low-Power RF Group.