Ambient temperature and relative humidity sensing using ultrasound signals

A method comprising:

• emitting, using a speaker of a device, an ultrasound signal in an environment around the device, wherein the ultrasound signal is a single chirp comprising a Zadoff-Chu (ZC) sequence modulated using an Orthogonal Frequency-Division Multiplexing (OFDM) modulation scheme;
• determining, using the ultrasound signal received via a microphone of the device, a signal component corresponding to a direct propagation path (DPP) between the speaker and the microphone;
• determining, using the signal component, a first sound propagation property representing a speed of the ultrasound signal along the DPP;
• determining, using the signal component, second sound propagation properties, wherein sound propagation property of the second sound propagation properties represents a sound attenuation of the ultrasound signal along the DPP in a respective frequency band of a plurality of frequency bands;
• and
• determining an ambient temperature value and a relative humidity value of the environment based on the first sound propagation property and the second sound propagation properties.

A method comprising:

• emitting an ultrasound signal using a speaker of a device, wherein the ultrasound signal is a single chirp comprising a Zadoff-Chu (ZC) sequence modulated using an Orthogonal Frequency-Division Multiplexing (OFDM) modulation scheme;
• determining, using the ultrasound signal received using a microphone of the device, a signal component corresponding to a direct propagation path (DPP) between the speaker and the microphone;
• determining, using the signal component, a first sound propagation property representing a speed of the ultrasound signal along the DPP;
• determining, using the signal component, second sound propagation properties, wherein each sound propagation property of the second sound propagation properties each represents a sound attenuation of the ultrasound signal along the DPP in a respective frequency band of a plurality of frequency bands;
• estimating an ambient temperature value based only on the first sound propagation property;
• and
• estimating a relative humidity value using a regression model corresponding to the ambient temperature value and based on the first sound propagation property and the second sound propagation properties.