Amazon’s AWS is integrating the Alexa Voice Service (AVS) with its AWS IoT Core. The AVS for AWS IoT (see figure) support lets the cloud handle AVS chores initiated on an IoT Core device, reducing memory and performance requirements. It enables voice support to be added to existing platforms with minimal overhead while also reducing the bill of materials needed for new devices.
The support targets devices such as thermostats and light switches, where cost and footprint can be an issue. In some cases, the audio support is already part of the design. AVS for AWS IoT lets developers include voice support as part of their application.
Alexa Voice Service (AVS) with its AWS IoT Core uses a secure connection to send audio messages to the cloud where commands can be initiated and completed on the device.
The IoT device running AWS IoT Core will have a private key that’s used to authenticate the device with the cloud-based services. The cloud has a matching public key, which is registered on the AVS Developer Portal. A Devicetype ID and Login with Amazon (LWA) credentials is used to connect and authenticate the device using the AVS API.
The new voice support adds a set of reserved MQTT topics that are used with the AVS. With the secure MQTT connection to the cloud, the AWS cloud is able to process the audio data and send the response back to the AWS IoT Core device.
The new support is designed for microcontrollers like the ARM Cortex-M. Prior Alexa voice support used over 50 MB of memory and ran on operating systems like Linux and Android. This latest support can be handled by devices with less than 1 MB of memory total. They typically run a more compact RTOS like AWS’ FreeRTOS.
AVS for AWS IoT is already being used in devices like iDevices smart-home products. Development kits such as NXP’s i.MX RT 106 A and Qualcomm’s Home Hub 100 Development Kit for Amazon AVS incorporate support for AWS IoT Core and AVS for AWS IoT. This includes out-of-the box connectivity to AWS IoT Core, AVS qualified Audio Algorithms for Far-Field voice pickup, Echo Cancellation, Alexa Wake Word, and AVS for AWS IoT application code.
