The AP and BP of the mobile phone can refer to the hardware and software based on the context.
1) Most mobile phones contain two processors. The operating system, user interface, and application are all executed on the application processor (AP). The AP generally uses the cpu Of the ARM chip. The Mobile Phone RF communication control software runs on another separate CPU, which is called baseband processor (BP ).
The main reason for putting RF functions on BP is that RF control functions (signal modulation, coding, RF displacement, etc.) are highly time-related. The best way is to put these functions on a master CPU for execution, and the master CPU runs the real-time operating system.
Another advantage of using BP is that once it is well designed and certified, no matter how the operating system and application software you use change, it can execute the function correctly (its communication function ). In addition, operating system and drive bugs do not cause devices to send catastrophic data to mobile networks. (Required by the FCC)
Because AP and BP are separate devices, mobile phone designers can design user interfaces and applications more freely.
2) mobile phone developers, such as Motorola, will divide the developed mobile phone software package into AP and BP. The software package running in application processor (AP) is called AP package, including the operating system, user interface, and applications. software packages related to baseband processor (BP) are called BP packages, including the communication control software of baseband modem. correspondingly, the so-called refresh mobile phone AP and BP file is to update these two software packages to the mobile phone. to facilitate flash, you can also integrate the AP, BP, and flex files (cell phone parameter configuration files.