Methods for handling data transmission by a mobile station with multiple radio frequency transceivers and systems utilizing the same

A method for handling data transmission by a mobile station with a first radio frequency (RF) module coupled to a first subscriber identity card and a second RF module coupled to a second subscriber identity card, comprising:

• assigning the first RF module to transmit a first packet originally having a source IP address IP(U) and a destination IP address IP(Y) corresponding to an access network;
• tunneling the first packet with a first new packet header comprising a source IP address IP(A) and a destination IP address IP(W);
• transmitting the tunneled first packet to the access network via the first RF module;
• assigning the second RF module to transmit a second packet originally having the source IP address IP(U) and the destination IP address IP(Y);
• tunneling the second packet with a second new packet header comprising a source IP address IP(B) and the destination IP address IP(W);
• transmitting the tunneled second packet to the access network via the second RF module.

A system for handling data transmission between a mobile station with two radio frequency (RF) modules and an access network, comprising:

• a first radio frequency (RF) module, coupled to a first subscriber identity card, corresponding to an IP address IP(A);
• a second radio frequency (RF) module, coupled to a second subscriber identity card, corresponding to an IP address IP(B);
• and
• a processor performing network address translation (NAT) to assign a portion of packets to be transmitted by the first RF module and assign another portion of packets to be transmitted by the second RF module;
• wherein the processor replaces a source IP address of a packet with IP(A) if assigning to the first RF module, and replaces with IP(B) if assigning to the second RF module.