Hotphrase triggering based on a sequence of detections

A system comprising:

• data processing hardware;
• and
• memory hardware in communication with the data processing hardware, the memory hardware storing instructions that when executed on the data processing hardware cause the data processing hardware to perform operations comprising:
• receiving audio data corresponding to an utterance spoken by a user and captured by a user device associated with the user, the utterance comprising:
• a command for a digital assistant to perform an operation;
• a hotphrase associated with a set of trigger words;
• and
• one or more other words not associated with the hotphrase that are spoken between a first trigger word in the set of trigger words and a last trigger word in the set of trigger words;
• during each of a plurality of fixed-duration time windows of the audio data:
• determining, using a hotphrase detector configured to detect each trigger word in the set of trigger words associated with the hotphrase, that the first trigger word in the set of trigger words is detected in the audio data during the corresponding fixed-duration time window;
• after determining that the first trigger word in the set of trigger words is detected in the audio data during the corresponding fixed-duration time window, determining that each other trigger word in the set of trigger words associated with the hotphrase is also detected in the audio data during the corresponding fixed-duration time window;
• determining that a sequence of the set of trigger words detected in the audio data during the corresponding fixed-duration time window matches a predefined sequential order associated with the hotphrase;
• and
• based on determining that the sequence of the set of trigger words detected in the audio data during the corresponding fixed-duration time window matches the predefined sequential order associated with the hotphrase, identifying, in the audio data corresponding to the utterance, the hotphrase;
• and
• triggering an automated speech recognizer (ASR) to perform speech recognition on the audio data when the hotphrase is identified in the audio data corresponding to the utterance.