Abstract: A base station management system is provided in the invention. The base station management system includes a base station management device and a first base station. The base station management device manages a plurality of base stations. The first base station sends a first link request to the base station management device based on a default port number and a base station management device address through a communication interface. After the base station management device receives the first link request, the base station management device establishes a link with the first base station based on the first link request, and changes the port number corresponding to the first base station from the default number to an unused first port number to release the default port number. The first base station establishes the link with the base station management device again based on the first port number.

Abstract: An In-Flight Entertainment system is provided with a server unit and a display unit. The server unit is configured to maintain digital content. The display unit is configured to connect to the server unit through a wired network for receiving and presenting the digital content. The display unit further includes a wireless module for wirelessly transmitting the digital content received from the server unit to be presented by a first portable device.

Abstract: Bandgap reference circuits capable operating in low voltage environments. In the bandgap reference circuit, a current generation circuit generates an output current obtained by combining a first current, a second current and a third current. The first current is converted from a first voltage and a first forward voltage of a first constant voltage generation element. The second current and the third current are both converted from a voltage difference between the first forward voltage and a second forward voltage of the second constant voltage generation element. A current-to-voltage generator converts the output current to an output voltage.