Phone expanding unit

The utility model provides a phone expanding unit, is including being used for receiving communication signal and carrying out black switch, and respectively with the switch with the decoder that the phone is connected, wherein, be equipped with in the switch and be used for receiving communication signal's receiving module and encrypt the integrated circuit board, be equipped with encryption CPU and encrypt FPGA in encrypting the integrated circuit board, it is used for receiving to encrypt CPU the communication signal that receiving module sent analyzes and sends to encrypt FPGA, it is used for encrypting and distributing to the communication signal after the analysis to encrypt FPGA the decoder, the decoder is used for receiving switch encrypted communication signal decrypts, and will decrypt after communication signal send for the phone. The utility model discloses in, through in the switch encrypt the integrated circuit board and encrypt the rethread to communication signal the decoder sends to after dec