The electronic device of the present invention may comprise: a first antenna and a second antenna; a communication circuit; and a processor electrically connected to the first antenna, the second antenna, and the communication circuit. The processor is configured to: control the communication circuit such that a first signal is output to the first antenna; acquire a second signal corresponding to the first signal reflected from the first antenna, and a third signal corresponding to the first signal output through the first antenna and received by the second antenna; identify a reflection coefficient at which the first signal is reflected from the first antenna, and a transmission coefficient at which the first signal is transmitted to the second antenna; and perform a designated function according to a value corresponding to a distance between the electronic device and an external object.