How to Make Smart Homes Even Smarter?

The impact of voice-controlled digital assistants such as Amazon Alexa, Google Assistant, Apple Siri, Microsoft Cortana and Samsung Bixby cannot be overstated. Consumers are using voice commands for turning on the lights, streaming music, asking questions and accessing third-party services in record numbers. Interacting directly with smart home assistants has created a new sales channel: shop by voice.

CTA projected consumers would buy 4.4 million Amazon Alexa and Google Home devices during the 2017 holiday season, up 22 percent, in its U.S. Consumer Technology Sales and Forecasts. The report pegged 2017 sales in the smart home category at 27 million units (a 50 percent increase over 2016), earning $3.3 billion (a 48 percent increase).

These smart assistants work pretty much the same way. There is a trigger phrase that captures the system’s attention, such as Apple’s “Hey Siri,” which lets users invoke Siri hands-free. This isn’t as simple as it seems. A very small speech recognition engine — the Apple iPhone calls it the “Always-on Processor” — has access to the microphone signal and runs all the time, listening for those two words.

The “Hey Siri” detector uses a Deep Neural Network (DNN) to convert the acoustic pattern of your voice into a probability distribution over speech sounds. It then computes a confidence score to confirm you said “Hey Siri.” If the score is high enough, Siri wakes up.

The audio input that follows in each digital assistant then is transmitted to the cloud for processing via Wi-Fi. A smart device equipped with Bluetooth first sends its audio file to a smartphone and then transmits the file to the cloud using a cellular or Wi-Fi connection. Placing the main voice recognition engine in the cloud efficiently eliminates the need for dedicated resources in the device.

If they work the same way, how can suppliers make these smart assistant devices smarter?

Involve More Developers

With the competition to build digital assistant products intensifying, success will depend on how well they perform, but also the ecosystem to which they connect. The ease that third-party developers can integrate voice-control technology into their products is critical.

Intel released the Intel Speech Enabling Developer Kit for Amazon Alexa that provides an audio frontend solution for voice control. It includes algorithms for acoustic echo cancelation, noise reduction, beamforming (a signal processing technique used for directional signal transmission or reception) and a custom wake-word engine tuned to “Alexa.” It also comes with dual Intel DSPs and an eight-microphone circular array.

Similarly, Cirrus Logic’s Voice Capture Development Kit for Alexa Voice Service (AVS) is optimized for the development of Alexa-enabled smart speakers, portable speakers and compact audio devices. It includes a reference board that features Cirrus Logic’s CS47L24 smart codec, CS7250B digital MEMS (microelectromechanical systems) microphones and “SoundClear” algorithms for voice control, noise suppression and echo cancelation. The turnkey voice capture reference design enhances “Alexa” wake word detection and audio capture in real-world conditions, even from moderate distances and in noisy environments.

Get a Clean Audio Signal

This increases the chances that the voice recognition engine will understand what’s being asked of it. The application of MEMS technology led to the development of small, high-performance microphones supporting user interactions with “smart” devices. Polysilicon is the material often used as a membrane for microphone devices. But this material is brittle and defects can occur during manufacturing.

At the AVS International Symposium & Exhibition in Tampa, FL, researchers from WPI-Advanced Institute for Materials Research/Micro System Integration Center at Japan’s Tohoku University presented a potential replacement material — amorphous metallic glass (cobalt tantalum boron) and it shows promise for MEMS mics from a manufacturing standpoint and also from the perspective of achieving high signal to noise ratios.

Provide Short Range, Very High-Speed Transfer of 4K/HDR Video

The IEEE standard 802.11ad could play a role using the 60 GHz spectrum instead of the 5 GHz and 2.4 GHz used by most Wi-Fi connections. It provides data throughput speeds of up to 7 Gbps (vs. 3.2 Gbps for the current speed champion, 802.11ac Wave 2). Since it uses frequencies in the millimeter range 802.11ad, its range is limited to about 30 feet. For high volume data exchange such as 4K video transfers or streaming from your smart device to your smart TV it should work well. But when longer ranges are needed, the Wi-Fi 802.11ac version is a better choice to provide the best consumer experience.