Method for selecting an antenna in a system comprising a first device and at least one second, mobile device, the system forming a communication network in which the first device communicates with the at least one second device by using a medium access technique of time-division multiple access type in which each communication is done in frames, each frame being divided into a plurality of time slots comprising a first time slot allowing the first device to transmit a first signal intended for the second device and allowing the second device to be synchronized in time on a time reference of the first device, and a second time slot allowing the second device to transmit a second signal in response to the first signal to acknowledge its presence in the system, the first device transmitting and receiving the signals via an antenna system comprising at least a number N of sectoral antennas with N greater than or equal to four and one omnidirectional antenna, characterized in that the method comprises the steps executed by the first device of: - obtaining, in an acquisition mode, for each antenna of the antenna system, a first information item representative of a communication quality between the antenna and the second device; - selecting, from the first information items representative of a communication quality that are obtained, the antenna for which the first information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device; - obtaining, in a so-called tracking mode, if the selected antenna is a sectoral antenna, for the omnidirectional antenna and for each antenna of a group of M sectoral antennas comprising the selected sectoral antenna, with M strictly less than N, a second information item representative of a communication quality between the antenna and the second device; - selecting, from the second information items representative of a communication quality that are obtained, the antenna for which the second information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device; - obtaining, in the so-called tracking mode, for each antenna of the antenna system, a third information item representative of a communication quality between the antenna and the second device if the selected antenna is the omnidirectional antenna; - selecting, from the third information items representative of a communication quality that are obtained, the antenna for which the third information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device. - obtaining, in an acquisition mode, for each antenna of the antenna system, a first information item representative of a communication quality between the antenna and the second device; - selecting, from the first information items representative of a communication quality that are obtained, the antenna for which the first information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device; - obtaining, in a so-called tracking mode, if the selected antenna is a sectoral antenna, for the omnidirectional antenna and for each antenna of a group of M sectoral antennas comprising the selected sectoral antenna, with M strictly less than N, a second information item representative of a communication quality between the antenna and the second device; - selecting, from the second information items representative of a communication quality that are obtained, the antenna for which the second information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device; - obtaining, in the so-called tracking mode, for each antenna of the antenna system, a third information item representative of a communication quality between the antenna and the second device if the selected antenna is the omnidirectional antenna; - selecting, from the third information items representative of a communication quality that are obtained, the antenna for which the third information item representative of the communication quality is the highest, to transmit and/or receive data with the mobile device.