A method for selecting a target antenna, executed by a master access point, comprising the following steps: a) receiving operating information of every antenna of every access point (AP1∼AP4) within a local area network, wherein each access point includes one or more antennas; b) determining whether or not multiple antennas of one or multiple access points are in an idle state based on data throughput included in the operating information of the multiple antennas of the multiple access points (AP1∼AP4), in response to determining that the multiple antennas are in the idle state, selecting one of the antennas in the idle state as the target antenna and then performing the step (e), and in response to determining that none of the multiple antennas is in the idle state, performing step (c); c) comparing the data throughput of the antennas of the multiple access points (AP1∼AP4) according to the operating information to select one of the multiple antennas that has the lowest data throughput; d) determining whether the data throughput of the selected antenna is lower than a data throughput threshold or not, in response to determining that the data throughput of the selected antenna is lower than the data throughput threshold, selecting the antenna having the data throughput lower than the data throughput threshold as the target antenna, and in response to determining that the data throughput of the selected antenna is not lower than the data throughput threshold, returning to the step a); and e) instructing the target antenna to scan for signals in operating channels of the access points (AP1∼AP4) that are under regulation of dynamic frequency selection, or for background noise in the operating channels of the access points (AP1∼AP4) that are under regulation of dynamic frequency selection, within a frequency band specified by the master access point; f) instructing the access points (AP1~AP4) to switch their operating channels to other channels each having a bandwidth that reaches a bandwidth threshold, when the signals scanned by the target antenna contain radar signals or the background noise exceeds a threshold. a) receiving operating information of every antenna of every access point (AP1∼AP4) within a local area network, wherein each access point includes one or more antennas; b) determining whether or not multiple antennas of one or multiple access points are in an idle state based on data throughput included in the operating information of the multiple antennas of the multiple access points (AP1∼AP4), in response to determining that the multiple antennas are in the idle state, selecting one of the antennas in the idle state as the target antenna and then performing the step (e), and in response to determining that none of the multiple antennas is in the idle state, performing step (c); c) comparing the data throughput of the antennas of the multiple access points (AP1∼AP4) according to the operating information to select one of the multiple antennas that has the lowest data throughput; d) determining whether the data throughput of the selected antenna is lower than a data throughput threshold or not, in response to determining that the data throughput of the selected antenna is lower than the data throughput threshold, selecting the antenna having the data throughput lower than the data throughput threshold as the target antenna, and in response to determining that the data throughput of the selected antenna is not lower than the data throughput threshold, returning to the step a); and e) instructing the target antenna to scan for signals in operating channels of the access points (AP1∼AP4) that are under regulation of dynamic frequency selection, or for background noise in the operating channels of the access points (AP1∼AP4) that are under regulation of dynamic frequency selection, within a frequency band specified by the master access point; f) instructing the access points (AP1~AP4) to switch their operating channels to other channels each having a bandwidth that reaches a bandwidth threshold, when the signals scanned by the target antenna contain radar signals or the background noise exceeds a threshold.