Tips for Choosing a Wake Word
A wake word is a special word or phrase that is meant to activate a device when spoken. It is also referred to as 'hotword', 'trigger word', and 'wake up word'. There are a few famous wake phrases such as "Hey Siri", "OK Google", and "Alexa".
A wake word should be unique and promote the brand of the device or application using it. Not all wake phrases are equal. A careful choice can substantially increase the accuracy.
Below are basic guidelines we gathered through numerous interactions with clients onboarding Picovoice's wake word engine, Porcupine.
Avoid Short Single-Word Phrases
Detecting short phrases is difficult for both humans and machines, especially in presence of noise and echo. Most well-known wake words have at least six phonemes: "OK Google" has eight phonemes and "Alexa" has six. Choosing a wake phrase with fewer than six phonemes is not recommended, because it is harder to detect and more likely to produce false positives.
A short wake word can be made more effective by prepending it with e.g. "Hey", or "OK". These prefixes can also help make it unambiguous that the wake phrase was intended to be triggered, and not simply a part of regular speech that accidentally matched the wake phrase.
Avoid Long Phrases
There is a trend to use shorter wake phrases. For example, Amazon has only single-word wake phrases and Google moved from "OK Google Now" to "OK Google". Longer multi-word wake phrases are cumbersome and can result in a poor user experience.
Choose Words with Diverse Sounds
Pick a phrase that has a variety of different sounds. Different phonemes create a more distinct signature and are less likely to create false alarms.