level of control of the os on the phone hardware

I am new to Android and mobile phones development. I want to develop an application that needs to have a total control over the "phone" of the smartphone, i.e. controlling all the communication of the GSM chip with the cellular system, accessing the SIM card identity that it sends (encrypted) to the cellular system, disabling the cellular antenna and resuming it back, and more of that kind... Can it be done with Android? Does the software (OS) have control over all of the phone components in a smartphone, or there are some parts that are done in the hardware level only? (I guess that the Android API won't enable me to do everything i want, but even theoretically is it possible if I recompile the OS afte开发者_如何学JAVAr making the changes there?) Thanks!

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but even theoretically is it possible if I recompile the OS

Yes everything is possible with custom firmware.