Determining power difference in sensor signals

An apparatus, comprising:

• a ultrasound sensor array to transmit ultrasonic signals into a pregnant woman and receive ultrasonic signals;
• a power source to provide power to the ultrasound sensor array;
• and
• a processing resource to determine differences between power in the transmitted ultrasonic signals and power in the received ultrasonic signals,
• wherein the processor is to determine a location of a fetal heart in relation to the ultrasound sensor array according to the differences in power.

A method for detecting fetal distress, comprising:

• transmitting a first ultrasonic signal via a first sensor into a pregnant woman;
• receiving a second ultrasonic signal via the first sensor from the pregnant woman;
• determining a first power difference according to a difference in a power of the first ultrasonic signal and a power of the second ultrasonic signal;
• transmitting a third ultrasonic signal via a second sensor into the pregnant woman;
• receiving a fourth ultrasonic signal via the second sensor from the pregnant woman;
• determining a second power difference according to a difference in a power of the third ultrasonic signal and a power of the fourth ultrasonic signal;
• comparing the first power difference and the second power difference;
• and
• determining a location of a fetal heart according to the comparison.