| By processing audio signal for different effects in sound field,audio processing system can effectively enhance the performance of sound quality.It has broad market prospect to used audio processing system in the field of car audio.Existing car audio system has big power consumption and poor anti-interference ability by using analog speaker.The emerging full digital speaker drives digital signals directly without going through complex processing and other digital-analog conversion,amplification and filtering.Thus it has higher working efficiency and integration,smaller size and power consumption,strong anti-interference ability.Currently there are few car audio processing systems with full digital speaker developed on the market.Full digital car audio processing system designed in this thesis aimed to support applications in digital speaker car stereo,with a powerful,easy adjustment,low power,personalized features and also compatible with existing analog car speakers.It has highly market economy value as well as an important significance on the promotion of full digital and the development of new car audio system.The content of this thesis includes four aspects as below:First of all,Based on the analysis of the functional requirements and performance requirements from car audio processing system,this thesis determines that system architecture is MCU + DSP dual core and controlling software is developed based on uITRON operating system.this thesis designs the architectural structure of full digital car audio processing system which supports full digital speakers and can be used on vehicles.Then,hardware circuit design of full digital car audio processing system is completed.This thesis completes chip selection based on the requirements of high fidelity audio.Focus on application of full digital speakers,digital audio output unit is designed.By using USB interface,making the system can be adjust by smart terminals.Electrical supply state detection unit provides the basis for software to implement low power consumption management.Power unit is designed to meet the requirements of high efficiency,small amount of heat and strong anti-interference.Thirdly,software design of control unit from full digital car audio processing system is completed.According to the control functions that control unit requires in the system,this thesis designs communication protocol between control unit and other units.System software platform and applications has been specifically designed and implemented.Finally,the overall system has been tested.The results proved that system designed in this thesis is rational and meets the design requirements.Full digital car audio processing system designed in this thesis can support up to eight channels of digital speakers as well as two-channel analog speakers.It also can configure audio in the mobile terminal and play high-resolution music.System consumes in the sleep state is only 10.8mW,while working consumes properly is 7.8W.Compared with the conventional car audio system,the sound power is greatly reduced by the system proposed in this paper. |
PDF Full Text Request