Disclosed is an air conditioner system which comprises a plurality of units comprising at least one outdoor unit and a plurality of indoor units, wherein the plurality of units comprises a wireless communication module configured to perform wireless communication using a Sub-GHz frequency band between the plurality of units, wherein the wireless communication module includes: an encoder configured to encode a predetermined signal; a modulator configured to modulate the encoded signal according to Orthogonal Frequency Division Multiplexing (OFDM) using multiple subcarriers; at least one antenna having an antenna pattern formed in a Printed Circuit Board (PCB), and configured to output a signal based on the modulated signal; a demodulator configured to demodulate a signal, received from the at least one antenna, according to the OFDM; and a decoder configured to decode the demodulated. Accordingly, a high-quality wireless communication environment may be implemented.