A New Interphone Implementing Immediate Communication With The Help Of GSM

Along with the rapid development of the global economic and living standard, interphone and mobile phone are used increasingly. Interphone and mobile phone are used as important communication tools, and may be used as best personal electronic equipments because they are only used by the owner and can access network wirelessly at anytime and anywhere. Typical technologies of new generation mobile phone such as Bluetooth, WAP and GPRS will drive mobile terminal developing rapidly. Developing more mobile terminals that have abundant functions such as mobile phone and interphone is urgent.This paper proposes a novel type of interphone, which implements immediate communication with the help of GSM system (we call it GSM interphone for short), and implements a prototype of the GSM interphone. The GSM interphone has advantages of both mobile phone and interphone. It can be used for immediate communication like mobile phone, but does not cause high communication cost like GSM mobile phone. It can also be used for group communication like the general interphone, however, no communication frequency need to be appointed in advance. The GSM interphone has more advantages than other similar products such as PoC, which uses VoIP technology based on GPRS (General Packet Radio Service). Compared with voice communication based on circuit switching, PoC has worse real time performance and higher error rate. Therefore, it has worse voice quality and longer voice delay. GSM interphone dose not have this problems, further more, it has lower cost than PoC and does not need any service support of network operators. Hence, GSM interphone is more convenient and has higher application value.