An electronic device and method related to measurement of an electromagnetic (EM) signal emitted from an external electronic device. The electronic device including a processor, a memory, and an EM sensor. The memory stores instructions, which, when executed, enable the processor to: obtain an input signal including an electromagnetic signal of an external electronic device and a self-noise using the EM sensor; identify an ambient condition of the electronic device; identify a compensation self-noise corresponding to the ambient condition; generate a signal pattern, based on the input signal and the compensation self-noise; and identify the external electronic device, based on at least a part of the signal pattern.