Signal transmission device and smart tv

A signal transmission device applied to a smart TV, the smart TV comprising a wireless signal module, wherein the signal transmission device comprises:

• a main antenna having a first signal input port, wherein the first signal input port is connected with the wireless signal module;
• a transmission antenna adjacent to and spaced from the main antenna, wherein the transmission antenna has a signal output port;
• and
• a dead-zone compensating antenna having a second signal input port, wherein the second signal input port is connected with the signal output port through a signal transmission line, and wherein
• the main antenna is configured to receive signals input by the wireless signal module and transmit the signals;
• the transmission antenna is configured to receive a part of the signals from the main antenna and transmit the part of the signals to the dead-zone compensating antenna through the signal transmission line;
• the dead-zone compensating antenna is configured to transmit signals received from the transmission antenna and compensate a signal dead zone of the main antenna.