Design And Implementation Of Digital Private Mobile Radio Baseband Chip Prototype

The digital private mobile radio technology is one of the inevitable trends of development of specialized mobile communication technology.DMR and dPMR standards have been launched in Europe. And China also released an RF regulation for digital private mobile radio. The bright market prospect of digital private mobile radio is the background of the thesis.The target of this thesis is to design and achieve digital private mobile radio baseband chip prototype based on dPMR protocol. The thesis is introduced from two general directions: the baseband software architecture and the peripheral hardware modules. Among them, the baseband software architecture consists of Calling Flow Design, dPMR protocol stack implementation, development of System-on-Chip (SoC)driver module and channel coding algorithm on Data Link Layer. On the other hand, the peripheral hardware contains various equipment that interact with the baseband chip, which describes the design of keyboard,LCD and RF circuit.The Finite State Machine is designed to achieve Calling Flow, which describe the transition between various states. dPMR standard employs FDMA stricture. With its channel bandwidth as 6.25KHz, dPMR has double bandwidth compared to current general 12.5KHz narrow-band system. So digital private mobile radio is used in a narrowband channel,its modulation rate is low. As a result of low modulation rate, its complexity of baseband processing isn't high. So using software for baseband processing is totally achievable. The protocol stack is introduced from the physical layer, the data link layer and the call control layer, focusing on implementation of channel coding algorithm on Data Link Layer. The design and implementation of the RS code algorithm ensure that the random errors and burst errors appear in the channel are effectively solved.For System-on-Chip (SoC) architecture, ARM microprocessor Cortex M series core chip as the MCU of the baseband chip prototype, the main module driver implementation to ensure the stability of the basic functions of the SoC. As the same time, multi-task management and scheduling can be achieved by real-time operating system (RTOS).In the peripheral hardware module, the matrix keyboard is used to input I/O information such as call number and service type. And LCD for the configuration information, 'business information, symbolic information display about digital private mobile radio. RF circuit for analog signal modulation and demodulation, which plays a decisive role in the entire Calling Flow.