wakeword

Wake word is a spoken word or phrase that activates a voice-controlled system. It is designed to be recognized by a detector that runs continuously in the device so the system can begin processing commands only after hearing the wake word. Common wake words include “Hey Siri,” “Okay Google,” and “Alexa.”

Technically, wake-word detection is a lightweight keyword-spots model that listens for a predefined term. The detector is optimized for low power and low latency, often running on-device, while the remainder of speech is processed by a full speech recognition pipeline when triggered. Some systems support user-defined wake words. In multilingual environments, detectors may support multiple wake words or switch languages.

Privacy and security considerations are central to wake-word design. On-device detection minimizes audio data sent to servers, but some implementations transmit audio for processing. Users may enable opt-in privacy controls, and manufacturers may implement local voice activity detection, encryption, and wake-word anonymization. Risks include false activations and potential spoofing by recordings or synthesized audio.

Applications and limitations: wake words enable hands-free use of smartphones, smart speakers, wearables, and car infotainment. Limitations include false positives, missed detections, latency, noise sensitivity, and energy consumption. Custom wake words can improve user experience but raise privacy and security considerations.

History: keyword spotting for wake words has roots in early speech research; modern consumer wake words entered mainstream with devices such as Siri in 2011, followed by Google Assistant and Amazon Alexa. Ongoing advances aim for more natural-sounding, multilingual, and privacy-preserving wake-word solutions.