Vdr Sound Design Of Data Acquisition Card

The fifth chapter of the SOLAS pact was passed in the 79th conference of IMO MSC in December ,2004. It requests that there must be a S-VDR or VDR on each of the watercraft at least after 1th , July, 2010.The sound of driver's room and communication voice must be recorded by VDR and S-VDR. The frequency of sound according to international request is ranged from 150Hz to 6000Hz. At the same time, the frequency of sound according to G.722.1 request is ranged from 50Hz to 7000Hz. It's easy to realize G.722.1 comparatively by use of DSP chip and it can realize the same quality as G.722 by the half bit rate of G.722. At present, the paper of VDR sound data acquisition card on the base of DSP and G.722.1 has not been released in public. This paper object is that design the sound acquisiton card of VDR.on the base of G.722.1. This paper introduces the design of sound acquisition form three parts, including system hardware, DSP software and FPGA software. The card of this paper design can acquire 5 channel sound data and the 24 hours data space is smaller than 1.2G.. It exhange data with PC through PC104 bus. This paper completes design of the software and the hardware, realize the playback of sound data and complete the frequency response testing of the card. This paper test the frequency response of the card on base PC sound card and the testing result indicate that restore signal change is smaller than 6dB.This paper provides some technical refernces for developing VDR.There are five chapters in this paper:The first chapter introduces development and market of the VDR and S-VDR.The second chapter introduces the system design and hardware architecture.The third chapter introduces the software design of DSP, inculding DSP main fuction, DSP initializtion function and data processing fucntion. The forth chapter introduces the software of FPGA from 5 aspects, including designe of FPGA top module, HPI_port module,SRAM_port module,SRAM_reader module and ISA_port module.The last chapter introduces the frequecy respose testing of the card.