Electronic Devices with Background-Cancelled Ultra Short Range Object Detection

A method of operating wireless circuitry, the method comprising:

• transmitting, using a transmitter and a radio-frequency transmission line path, a first signal;
• receiving, using a receiver, a second signal;
• estimating, using the one or more processors, a range to an external object farther than a threshold distance from the wireless circuitry based on the first signal and the second signal;
• generating, using a sensor, a first sensor measurement while a wireless performance level of the wireless circuitry is within a predetermined range;
• generating, using the sensor, a second sensor measurement while the wireless performance level is outside of the predetermined range of wireless performance metric values;
• and
• estimating, using the one or more processors, that the external object is closer than the threshold distance from the wireless circuitry while a difference between the second sensor measurement and the first sensor measurement exceeds a threshold value.

A method of operating wireless circuitry, the method comprising:

• transmitting, using a first radio-frequency transmission line path, a first signal;
• receiving, using a second radio-frequency transmission line path, a second signal;
• detecting, using one or more processors, an external object greater than a threshold distance away based on the first signal and the second signal;
• detecting, using a sensor communicatively coupled to the first radio-frequency transmission line path, the external object while the external object is located within the threshold distance, wherein detecting the external object while the external object is located within the threshold distance includes
• measuring a first sensor value while a wireless performance metric of the wireless circuitry is within a predetermined range of values, and
• measuring a second sensor value while the wireless performance metric is outside the predetermined range of values.