A multi-antenna array system comprising: active antennas (AA_1,..., AA_N) each of which includes an antenna element (AE_1,..., AE_N) and an amplifier (PA_1,..., PA_N) that includes a matching circuit (MN_1,..., MN_N); a failure detector; and a circuit controller, wherein the failure detector is configured to detect a failure in each of the active antennas (AA_1,..., AA_N), and the circuit controller is configured to change the matching conditions of the matching circuits so that: when there is no active antenna (AA_1,..., AA_N) having a failure, in each of the active antennas (AA_1,..., AA_N), a matching condition of the matching circuit (MN_1,..., MN_N) included in the amplifier (PA_1,..., PA_N) is set to a first condition defined by a standard for maximizing a power utilization efficiency of the amplifier (PA_1,..., PA_N), when there is one or more active antennas (AA_1,..., AA_N) having a failure, a matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure is set to a second condition defined by a standard for maximizing an output power of the amplifier (PA_1,..., PA_N), and when a failure in any of the active antennas (AA_1,..., AA_N) is detected, the circuit controller performs control to change the matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure from the first condition to the second condition. active antennas (AA_1,..., AA_N) each of which includes an antenna element (AE_1,..., AE_N) and an amplifier (PA_1,..., PA_N) that includes a matching circuit (MN_1,..., MN_N); a failure detector; and a circuit controller, wherein the failure detector is configured to detect a failure in each of the active antennas (AA_1,..., AA_N), and the circuit controller is configured to change the matching conditions of the matching circuits so that: when there is no active antenna (AA_1,..., AA_N) having a failure, in each of the active antennas (AA_1,..., AA_N), a matching condition of the matching circuit (MN_1,..., MN_N) included in the amplifier (PA_1,..., PA_N) is set to a first condition defined by a standard for maximizing a power utilization efficiency of the amplifier (PA_1,..., PA_N), when there is one or more active antennas (AA_1,..., AA_N) having a failure, a matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure is set to a second condition defined by a standard for maximizing an output power of the amplifier (PA_1,..., PA_N), and when a failure in any of the active antennas (AA_1,..., AA_N) is detected, the circuit controller performs control to change the matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure from the first condition to the second condition. when there is no active antenna (AA_1,..., AA_N) having a failure, in each of the active antennas (AA_1,..., AA_N), a matching condition of the matching circuit (MN_1,..., MN_N) included in the amplifier (PA_1,..., PA_N) is set to a first condition defined by a standard for maximizing a power utilization efficiency of the amplifier (PA_1,..., PA_N), when there is one or more active antennas (AA_1,..., AA_N) having a failure, a matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure is set to a second condition defined by a standard for maximizing an output power of the amplifier (PA_1,..., PA_N), and when a failure in any of the active antennas (AA_1,..., AA_N) is detected, the circuit controller performs control to change the matching condition of the matching circuit (MN_1,..., MN_N) included in each of the active antennas (AA_1,..., AA_N) not having a failure from the first condition to the second condition.