An antenna device, comprising: a near field communication chip comprising a first differential signal port and a second differential signal port, the first differential signal port and the second differential signal port being configured to provide a differential excitation current; a ground plane comprising a first ground point and a second ground point spaced apart from each other, wherein a conductive path is formed between the first ground point and the second ground point; a plurality of first conductive assemblies, each of the plurality of first conductive assemblies comprising a first feed port and a first ground port spaced apart from each other, the first ground port being electrically coupled to the first ground point; a first switch comprising a first fixed port and a first gate port, the first fixed port being coupled to the first differential signal port, the first gate port being coupled to the first feed port of each of the plurality of first conductive assemblies, the first switch configured to selectively allow the first differential signal port to be in communication with one or more first conductive assemblies from the plurality of first conductive assemblies; a second conductive assembly comprising a second feed port and a second ground port spaced apart from each other, the second feed port being electrically coupled to the second differential signal port, and the second ground port being electrically coupled to the second ground point; and a first control circuit electrically coupled to the first switch and configured to control the first switch to selectively allow the first differential signal port to be in communication with the one or more first conductive assemblies, wherein the one or more first conductive assemblies in communication with the first differential signal port, the conductive path, and the second conductive assembly together constitute a conductive loop for transmission of the differential excitation current, and wherein the first control circuit is configured to: detect a distance between each of the plurality of first conductive assemblies and an external object; determine a target first conductive assembly from the plurality of first conductive assemblies according to the detected distances, the target first conductive assembly being a conductive assembly from the plurality of first conductive assemblies having the smallest distance from the external object; and control the first switch to allow the first differential signal port to be in communication with the target first conductive assembly. a near field communication chip comprising a first differential signal port and a second differential signal port, the first differential signal port and the second differential signal port being configured to provide a differential excitation current; a ground plane comprising a first ground point and a second ground point spaced apart from each other, wherein a conductive path is formed between the first ground point and the second ground point; a plurality of first conductive assemblies, each of the plurality of first conductive assemblies comprising a first feed port and a first ground port spaced apart from each other, the first ground port being electrically coupled to the first ground point; a first switch comprising a first fixed port and a first gate port, the first fixed port being coupled to the first differential signal port, the first gate port being coupled to the first feed port of each of the plurality of first conductive assemblies, the first switch configured to selectively allow the first differential signal port to be in communication with one or more first conductive assemblies from the plurality of first conductive assemblies; a second conductive assembly comprising a second feed port and a second ground port spaced apart from each other, the second feed port being electrically coupled to the second differential signal port, and the second ground port being electrically coupled to the second ground point; and a first control circuit electrically coupled to the first switch and configured to control the first switch to selectively allow the first differential signal port to be in communication with the one or more first conductive assemblies, wherein the one or more first conductive assemblies in communication with the first differential signal port, the conductive path, and the second conductive assembly together constitute a conductive loop for transmission of the differential excitation current, and wherein the first control circuit is configured to: detect a distance between each of the plurality of first conductive assemblies and an external object; determine a target first conductive assembly from the plurality of first conductive assemblies according to the detected distances, the target first conductive assembly being a conductive assembly from the plurality of first conductive assemblies having the smallest distance from the external object; and control the first switch to allow the first differential signal port to be in communication with the target first conductive assembly. detect a distance between each of the plurality of first conductive assemblies and an external object; determine a target first conductive assembly from the plurality of first conductive assemblies according to the detected distances, the target first conductive assembly being a conductive assembly from the plurality of first conductive assemblies having the smallest distance from the external object; and control the first switch to allow the first differential signal port to be in communication with the target first conductive assembly.