Smart sensors detect human presence and enable optimal performance and standards compliance.

Since the start of the COVID-19 pandemic, the time consumers spend on their devices—computers, tablets, and smartphones—has dramatically increased. According to eMarketer, in 2020, adults in the U.S. spent more than seven hours per day on their smartphones, desktops, and other devices. eMarketer expects such usage to rise even more, surpassing eight hours per day by the end of 2022. Similarly, a study of 11,000 RescueTime users found the average respondent picked up his or her phone 58 times per day.

As the rise in screen time increased, a Statista survey reported that the average American had access to more than 10 connected devices in their household. Additionally, Fortune Business Insights reports that the consumer electronic market is projected to grow from $689.45 billion in 2020 to $989.37 billion in 2027.

Understanding what consumers—especially remote workers—expect out of their devices is critical. The requirements are simple: consumers are seeking CE products that deliver stable connectivity and long battery life while also complying with industry regulations.

Virtual employees do not want to worry about network lags, failed email deliveries, or dropped conference calls. This means that original equipment manufacturers (OEMs) need to develop products that balance performance and connectivity while meeting industry compliance requirements. With the help of smart proximity sensing, these products can run efficiently at peak performance and maintain compliance at all times.

Driving factors for compliance regulations 

In 1996, the Federal Communications Commission (FCC) adopted practices to ensure mobile phones, laptops, and tablets adhere to regulated levels of radio frequency (RF) output power in the presence of a human body. The limits specified by the FCC are rated in terms of Specific Absorption Rate (SAR), which is a measure of the amount of RF energy absorbed by a human body when using a wireless device.

Connected devices sold in each market are tested to ensure that they meet regulatory requirements. In the U.S., the FCC sets the SAR limit to be 1.6 watts per kilogram (over 1g of tissue) with a separation distance of 25 mm from the user. The European standard is 2 watts per kilogram (over 10g of tissue) with a separation distance of 5mm from the body.

Smart proximity sensors help maintain global compliance and improve RF performance in smartphones, tablets, and laptops. By monitoring human presence, smart sensors enable active RF power management when a user is in close proximity. These sensors are highly accurate, ensuring that the device is operating at peak performance and in compliance at all times.

Smart human sensors can distinguish between a human and an object and adjust power levels accordingly. For example, the device will lower RF power when it is being used in a consumer’s pocket or in the user’s hand. If the sensors detect an object instead of human, RF power can be maintained, thus ensuring optimal RF performance.

Some of the most important features of intelligent sensors in connected devices are as follows:

Best-in-Class Detection Performance: Using an advanced analog front end (AFE) enables higher detection distance or smaller sensor area.

Increased Proximity Intelligence: This innovative smart sensing feature differentiates between human and inanimate objects to enhance device responsiveness and reliability.

Enhanced Stability Over Temperature: Enables low-temperature variation over a longer duration. This limits the chances of false human detections with environmental temperature changes.

To understand the workings of a smart RF sensor, consider the functions of a device with a 2-channel capacitive SAR controller (SX9320). With the two sensor inputs that feed to its smart engine for SAR, this can distinguish between an inanimate object and a human body. The chip feeds its decisions about nearby humans to an external processor via an I2C serial bus. When the chip senses something nearby, an alert is sent to the host processor to either determine the relative proximity distance or simply obtain an indication of detection.

Connectivity is essential for remote workers. Maintaining SAR compliance and designing devices that support the fastest 5G network can be a design challenge for OEMs. That being said, this is the ideal time for RF designers to address the challenges and deliver industry-compliant products ahead of a mass 5G adoption. According to Juniper Research, 5G smartphones are expected to reach $337 billion by 2025. That will be more than two-thirds of smartphones on the market.

As 5G networks rapidly grow, smart proximity sensors are vital to the future of widespread 5G implementation and adoption. In the design process, RF engineers have to add more RF antennas to accommodate additional network frequencies. This may introduce potential design challenges. Increased RF connectivity may lower a device’s battery performance.

With intelligent sensors, devices can support wireless standards from 5G to Wi-Fi 6, providing the best connectivity for users regardless of the device and the protocols it supports.

The future of intelligent sensors

Smart sensors detect human presence and enable optimal performance and standards compliance. Designed for connected devices, these sensors intelligently modify the RF transmission levels of connected devices when humans are in close range. As the number of remote workers continues to rapidly grow, OEMs must provide always-on connectivity, high performance, and longer battery life to allow workers to work anywhere at any time.

By embedding intelligent sensors in connected devices, OEMs deliver better consumer experiences by offering a variety of desirable benefits, including SAR compliance, increased performance, and impressive battery life. This means remote workers can rest assured that they can be productive whenever and wherever they choose to work.

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