Research On Wireless Marine Detecting Laser Spectrometer

Currently,laser spectrometer is widely used in marine monitoring.Laser induced fluorescence technique can be adopted to obtain the fluorescence information of chlorophyll and oil in seawater accurately by visual and non-contact measurement methods.At present,the equipment used for marine monitoring is generally bulky and costly,also cannot stay in ocean for long time due to the special characteristics of the marine environment,such as seawater corrosion,equipment power supply,which makes poor real-time capability in data collection and processing.For the above problem,a small,low-cost wireless ocean detection laser spectrometer is presented in this paper.In order to achieve the miniaturization and intelligence of the instrument,TI's DM642 DSP chip is used as the core of the spectrum data acquisition and procession.DSP which is a micro-processor for digital signal processing,has powerful hardware resources.With the use of Harvard architecture,the storage of program and data is separated.The high speed of its data processing up to grade the real-time spectral data acquisition and procession.According to the need of field detection and real-time analysis,the wireless communication technology is studied.On the basis of comparative analysis to the characteristics of several kinds of short distance wireless communication technology,the Bluetooth technology is presented as the wireless transmission scheme.The technology has the advantages of low cost,low power consumption,strong anti-interference ability and good compatibility.By the combination with the laser spectrometer acquisition and processing system,the wireless transmission of spectral data can be implemented successfully.The whole system is divided into hardware and software.The hardware part mainly includes five modules,the laser control module,the video coding module,the DSP processing module,the Bluetooth wireless transmission module and the power supply module.Each module is compared to select the appropriate device,the application circuit designing is based on the manual of the chip.In software part,using the CCS6.0 software to design the lower computer DSP program,accomplished the spectral data acquisition and processing,data transmission through Bluetooth.Using Android Studio to design the upper computer program,accomplished the spectral data wireless reception and curve display.The whole system was assembled in the shell with the size 15 cm × 10 cm × 4.8 cm,and the measurement range from 423 nm to 786 nm was determined by using high-pressure mercury lamp.The spectral acquisition and data processing were carried out at 720 × 576 resolution.Using the system to detect different kinds of ocean samples,through the analysis of fluorescence spectra,we can judge the presence of chlorophyll and oil in ocean and finish the expected function.