How to design sim card that should work on both facility to accept inter com signal and also a call frmoutside?

tranceivers are enough that to receive intercom calls in mobile but to attend calls frm outside n/w it is necessary to design another sim how to design tat sim?How to design sim card that should work on both facility to accept inter com signal and also a call frmoutside?Though I am a top contributor in this category but i ain't a telecommunication engineer so please post the question in 'ENGINEERING' category.