Dual Cards Dual Standby User-defined Firewall For Incoming Calls Based On MTK Platform

With the rapid development of information society, mobile phones have gradually become an indispensable part of life. When the mobile communications develop to a certain extent, many people expect to own or have owned a number of mobile phone numbers, especially for business men who are eager to carry multiple telephone numbers on their cell phones since they often need to travel and switch SIM cards. In accordance with the needs of the market, mobile phone can support two SIM cards at the same time, on which two cards can also dual-card dual standby appear. Dual card dual standby mobile phone can provide users with more convenient, intuitive, user-friendly personal communication services.During the early period dual-card mobile phone is able to be inserted two SIM cards at the same time, but only one card is active. Their switch is achieved by hardware circuits chosen at the boot time generally. Two SIM cards can not be switched dynamically during general state of the work for the impact of protocol stack. That is, each switch will need to restart the phone system. This mobile phone is often referred to as dual-card single question phone.Then a true dual-card dual-standby emerges which has two systems, namely, two sets of radio frequency (RF), two sets of base-band (Base Band) and two sets of protocol stacks at the same time .One of its most prominent feature is that cell-phone numbers on the same phone can call each other. This is the necessary condition determining whether the mobile phone is the dual-card double question or not.However, two systems on cell phone lead to high-cost, high-power, high complexity and larger size which become bottleneck for the development and popularity. Via continual improvement, the mobile phones run only a system and share a set of base band, a radio frequency co-ordination of the dual-card dual-standby are produced. Comparing with the previous two systems mobile phone, it is able to function well in the dual cards standby and have a significant cost reducing simultaneously. Since its advantages of low-power, low-cost, high-performance, the new dual-card double standby gets the rapid development and widespread use.The research of this paper is based on the MT6225 platform which is supplied by Taiwan's MediaTek (MTK) Company. With the understanding of MT6225 hardware and software development platform we investigate the dual-card double question of the single-chip mobile phone dual-card communication between control mechanisms; and focus on the mobile phone call control process based on GSM protocol; according to MMI interface development standards, make customized firewall features calls from time to time realize which is applicable to the realization of two-and dual-card mobile phone mobile phones, providing the follow-up optimal scheme including phone records of refusing to give access, SMS firewall. Through the simulation on PC and test on the mobile phone, the correctness of the various application functions and stability is verified. Combination of problems in the functional development process, we also present some methods of application and debug tips for testing tools.