Evolved packet core less direct mode communication system and communication attaching method thereof

An evolved packet core less (EPC-less) direct-mode communication system, comprising:

• a first client direct-mode communication apparatus;
• and
• a first server direct-mode communication apparatus;
• wherein the first server direct-mode communication apparatus transmits a synchronization signal to the first client direct-mode communication apparatus, and the first client direct-mode communication apparatus synchronizes to the first server direct-mode communication apparatus according to the synchronization signal, and creates a communication connection in the EPC-less direct-mode communication system after the synchronization.

A communication attaching method for a first client direct-mode communication apparatus, the first client direct-mode communication apparatus being used in an evolved packet core less (EPC-less) direct-mode communication system, the EPC-less direct-mode communication system further comprising a first server direct-mode communication apparatus, the communication attaching method comprising:

• (a) enabling the first client direct-mode communication apparatus to receive a synchronization signal from the first server direct-mode communication apparatus;
• (b) enabling the first client direct-mode communication apparatus to synchronize to the first server direct-mode communication apparatus according to the synchronization signal;
• and
• (c) enabling the first client direct-mode communication apparatus to create a communication connection in the EPC-less direct-mode communication system after the step (b).

A first client direct-mode communication apparatus for use in an EPC-less direct-mode communication system, the EPC-less direct-mode communication system comprising a first server direct-mode communication apparatus, the first client direct-mode communication apparatus comprising:

• a processor;
• and
• a transceiver;
• wherein the transceiver is configured to receive a synchronization signal from the first server direct-mode communication apparatus, and the processor is configured to synchronize to the first server direct-mode communication apparatus according to the synchronization signal and create a communication connection in the EPC-less direct-mode communication system via the transceiver after the synchronization.

A server direct-mode communication apparatus for use in an EPC-less direct-mode communication system, the EPC-less direct-mode communication system further comprises a first client direct-mode communication apparatus, the server direct-mode communication apparatus comprising:

• a processor;
• and
• a transceiver;
• wherein the transceiver is configured to transmit a synchronization signal to the first client direct-mode communication apparatus so that the first client direct-mode communication apparatus synchronizes to the server direct-mode communication apparatus according to the synchronization signal, and the processor is configured to directly create a communication connection with the first client direct-mode communication apparatus via the transceiver, wherein the server direct-mode communication apparatus is a second client direct-mode communication apparatus.

A communication attaching method for a server direct-mode communication apparatus, the server direct-mode communication apparatus being used in an EPC-less direct-mode communication system that further comprises a first client direct-mode communication apparatus and a second client direct-mode communication apparatus, the communication attaching method comprising:

• (a) enabling the server direct-mode communication apparatus to transmit a synchronization signal to the first client direct-mode communication apparatus and the second client direct-mode communication apparatus so that the first client direct-mode communication apparatus and the second client direct-mode communication apparatus synchronize to the server direct-mode communication apparatus according to the synchronization signal;
• (b) enabling the server direct-mode communication apparatus to receive a piece of first client information and a piece of second client information from the first client direct-mode communication apparatus and the second client direct-mode communication apparatus respectively after the step (a);
• and
• (c) enabling the server direct-mode communication apparatus to forward data of the first client direct-mode communication apparatus and the second client direct-mode communication apparatus according to the first client information and the second client information so that the first client direct-mode communication apparatus and the second client direct-mode communication apparatus create a communication connection therebetween.

A server direct-mode communication apparatus for use in an EPC-less direct-mode communication system, the EPC-less direct-mode communication system further comprising a first client direct-mode communication apparatus and a second client direct-mode communication apparatus, the server direct-mode communication apparatus comprising:

• a processor;
• and
• a transceiver;
• wherein the transceiver is configured to transmit a synchronization signal to the first client direct-mode communication apparatus and the second client direct-mode communication apparatus so that the first client direct-mode communication apparatus and the second client direct-mode communication apparatus synchronize to the server direct-mode communication apparatus according to the synchronization signal;
• the transceiver is further configured to receive a piece of first client information and a piece of second client information from the first client direct-mode communication apparatus and the second client direct-mode communication apparatus respectively;
• and the processor is configured to forward data of the first client direct-mode communication apparatus and the second client direct-mode communication apparatus via the transceiver according to the first client information and the second client information so that the first client direct-mode communication apparatus and the second client direct-mode communication apparatus create a communication connection therebetween.

A communication attaching method for a first server direct-mode communication apparatus, the first server direct-mode communication apparatus being used in an EPC-less direct-mode communication system that further comprises a first client direct-mode communication apparatus, a second client direct-mode communication apparatus and a second server direct-mode communication apparatus, the first server direct-mode communication apparatus and the second server direct-mode communication apparatus being synchronized to each other via a connection according to a synchronization signal, the communication attaching method comprising:

• (a) enabling the first server direct-mode communication apparatus to transmit the synchronization signal to the first client direct-mode communication apparatus so that the first client direct-mode communication apparatus synchronizes to the first server direct-mode communication apparatus according to the synchronization signal and transmits a piece of first client information to the first server direct-mode communication apparatus, wherein the second server direct-mode communication apparatus transmits the synchronization signal to the second client direct-mode communication apparatus so that the second client direct-mode communication apparatus synchronizes to the second server direct-mode communication apparatus according to the synchronization signal and transmits a piece of second client information to the second server direct-mode communication apparatus;
• and
• (b) enabling the first server direct-mode communication apparatus to exchange the first client information and the second client information with the second server direct-mode communication apparatus via the connection so that the first client direct-mode communication apparatus creates a communication connection with the second client direct-mode communication apparatus via the first server direct-mode communication apparatus and the second server direct-mode communication apparatus.

A first server direct-mode communication apparatus for use in an EPC-less direct-mode communication system, the EPC-less direct-mode communication system further comprising a first client direct-mode communication apparatus, a second client direct-mode communication apparatus and a second server direct-mode communication apparatus, the first server direct-mode communication apparatus and the second server direct-mode communication apparatus being synchronized to each other via a connection according to a synchronization signal, the first server direct-mode communication apparatus comprising:

• a processor;
• and
• a transceiver;
• wherein the transceiver is configured to transmit the synchronization signal to the first client direct-mode communication apparatus so that the first client direct-mode communication apparatus synchronizes to the first server direct-mode communication apparatus according to the synchronization signal and transmits a piece of first client information to the first server direct-mode communication apparatus, wherein the second server direct-mode communication apparatus transmits the synchronization signal to the second client direct-mode communication apparatus so that the second client direct-mode communication apparatus synchronizes to the second server direct-mode communication apparatus according to the synchronization signal and transmits a piece of second client information to the second server direct-mode communication apparatus;
• and the processor is configured to exchange the first client information and the second client information with the second server direct-mode communication apparatus through the transceiver and via the connection so that the first client direct-mode communication apparatus creates a communication connection with the second client direct-mode communication apparatus via the first server direct-mode communication apparatus and the second server direct-mode communication apparatus.