Page 6 - EE Times Europe March 2022

6 EE|Times EUROPE

COVER STORY

How Radar Sensors

Significantly Improve the

Energy Efficiency of the

Smart Home

BY BERND KOHLER, Product Manager and Marketer for IoT Radar Sensors, Infineon Technologies

The number of smart-home applications and connected devices is growing, making
everyday life more convenient for their users. Yet this results in high energy
consumption, as these devices are often permanently active or in standby mode in
order to be ready for use at all times — even though no one is present. By equipping
smart devices with the Infineon XENSIV™ 60-GHz radar sensor, they become more
energy-efficient and therefore smarter and more sustainable.

mart buildings and smart homes are that deactivates the PC monitor after a certain present. For some devices, this can save a
becoming increasingly popular, and time without mouse or keyboard input and few watts or a fraction of that. But there
their number is expected to grow reactivates it as soon as new input is noticed. are also use cases where you can save more
Ssignificantly in the coming years. Through this reliable presence and absence than 100 W if you put devices into a deep-
Already today, the number of smart homes detection, Infineon’s 60-GHz radar sensor sleep mode or temporarily switch them off
worldwide is estimated at more than powers the design of truly smart, energy- whenever no one is present and they are
200 million, and forecasts predict that this saving devices. therefore not needed — for example, the TV
figure will exceed 500 million within the next screen, the laptop, the sound system, and the
few years (Figure 1). ACTIVITY TRIGGERED BY USER PRESENCE air conditioner. By using a radar sensor, such
A house can become smart only through VERSUS CONTINUOUS ACTIVITY devices will be able to sense the presence
increasingly digitalized devices with more and OR STANDBY or movement of people; if these impulses
more ingenious functionalities. However, this According to a Statista survey conducted in remain absent, a radar-based smart device
comes at a high price: The need for energy is Germany in 2021 with 3,000 respondents aged can automatically switch to sleep mode and
growing, despite the previous trend of steadily 18 to 64 years, almost three-quarters own at save energy. Depending on the sensor and
declining standby power consumption. Smart least one smart-home device. In the U.S., the implementation, the radar module itself has
devices require energy even when they are figures are similar (Figure 2), while in China, a power consumption of only a few milliwatts
“off,” as being in standby mode is the only way the percentage of users of smart-home devices and a maximum power consumption of 0.1 W,
for them to react instantaneously to user input is as high as 90%. The devices are as diverse which is significantly lower than the energy
(e.g., via voice control) or to provide the latest as their applications: They include lighting; demand of the “on” or standard standby mode
information from the smart home or web. security devices; consumer electronics such of many electronic devices (Figure 3).
Furthermore, there are many occasions when as TVs, laptops, and soundbars; kitchen
it is completely unnecessary for a device to run appliances; and air conditioners. But all these HOW TO USE RADAR SENSORS
in standby mode and thus consume energy — devices are increasing the demand for energy, TO INCREASE ENERGY EFFICIENCY
primarily when no one is present. which is an undesirable effect, especially in To save energy, the approach that devices
To solve this issue and to meet the times of rising energy costs, when custom- must always be available and connected —
requirements of both digitization and energy ers prefer energy-saving, sustainable, and this includes power-hungry standby mode
efficiency, Infineon leverages its semiconduc- eco-friendly devices. Moreover, the grid infra- — needs to be reinvented. We require devices
tor solutions. One of them is the XENSIV™ structure is under increasing strain. that are only active or in standby when really
radar sensor, which can be applied to almost Instead of putting devices such as thermo- necessary — in other words, when users are
all smart-home devices. Radar sensors are stats, smart speakers, and digital assistants present. That is what we do today in our “non-
highly sensitive and can detect whether a into normal standby mode, one way to reduce smart” homes, when we switch on the lights
person is present and whether the device energy consumption would be to put them upon entering the room or manually activate
needs to be ready — similar to a screensaver into a “deep-sleep mode” when no one is the air conditioner only when it is getting too

MARCH 2022 | www.eetimes.eu