激光粒度仪是一种最先进的、最具有广泛发展前景的粒度测量仪器，它的测量原理基于米氏(Mie)散射理论。MIE散射理论是一个经典的光散射理论，它最大的特点是可用于任何尺寸段颗粒的测量，但它的计算相当复杂限制了数据处理速度及精度。

DSP技术实现MIE散射算法有很多优点：它是专为算法计算而设计的专用CPU，所以它运算速度很快；与通用CPU相比它成本低，所以有很好的性价比；而且它的体积小，能实现仪器一体化等等优点。 ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" 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title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM" title="ARM">ARM具有丰富的片上资源，适合嵌入式系统的开发，主要负责操作系统的运行、任务管理和协调以及DSP的控制任务，外部可扩展多种外设，如通用串口、LCD显示屏、以太网接口。

　　1 系统总体设计及工作原理

　　1．1 激光粒度仪工作原理

　　激光粒度仪的组成框图如图1所示。

　　激光粒度仪中的光电探测器采集颗粒在一定角度范围内的散射光来得到颗粒的粒径分布信息。由于光电探测器处在傅里叶透镜的焦平面上，因此探测器上的任一点都对应某一确定的散射角。光电探测器阵列由一系列同心环带组成，每一环带是一个独立的探测器，能将投射到上面的散射光能线性地转换成电压，然后送给采集卡。该卡将电信号放大，再进行A／D转换后送入计算机，按事先编制的程序根据米氏散射理论进行数据处理，把散射谱的空间分布反演为颗粒大小的分布。

　　1．2 电路系统的总体设计

　　激光粒度仪电路总体框图如图2所示。采集电路采集到的数据经过 RS232串口传输给DSP，经过DSP的运算后，再把DSP处理后得到的结果数据RS232经过串口传输给ARM处理器，在ARM处理器的触摸屏界面上显示结果。

　　2 电路系统具体设计方案

　　2．1 数据采集电路设计

　　粒度仪的光电探测器是用光电池做成多元环形，多元环形光电探测器接收散射光的光能量，环形光电池把光能量转换为光电流。然后经过电流电压转换器，把电流信号转换为电压信号。再经过放大电路放大，然后输入到A／D转换器，将模拟信号转换为数字信号。然后把数字信号输入到C805lF320单片机，单片机然后再传给DSP进行处理，如图3所示。

　　系统的硬件组成分为以下几个部分：环形光电探测器、数据选择部分、电流电压转换部分、运算放大部分、模数转换部分和中央单片机控制部分。

　　①模拟多路选择器选用ADG506，它精度高，为1mV，抗干扰能力强，功耗低，价格便宜；

　　②电流电压转换电路有起滤波作用的电容及可调电阻，有利于调整电路参数；

　　③滤波放大电路的二阶Butterworth低通滤波器截止频率为10Hz，主要滤除工频干扰；

　　④模数转换电路采用的芯片是 TLC2551，此芯片是14位A／D，输入电压范围为：O～5V；理论采集精度可达0．3mV，受实际测试条件所限制实际测试精度可达0．8mV；A／D转换时间为10m，采集速度很高；此芯片抗干扰能力强，功耗低，性价比高；

　　⑤控制电路采用C8051F320作为采集电路的控制芯片，它片上资源丰富，主频高可达25MHz，而且开发简单，性价比高。单片机采集来的数据通过串口发送给DSP芯片。

　　2．2 DSP运算电路的设计

　　DSP作为一种用的数字信号处理器，自从问世以来，DSP就以数字器件特有的稳定性，可重复性，可大规模集成，特别是可编程性和易于实现自适应处理的特点，给数字信号处理的发展带来了巨大的机遇。

　　激光粒度仪的采集电路采集来的数据通过RS232串口传送给DSP处理器，经过DSP进行算法运算，运算完成后再通过RS232串口传送给嵌入式ARM处理器显示结果。原理框图如下图4所示：

　　①DSP芯片选用TMS320C5416，TMS320C5416采用改进的哈佛结构，具有以下优点：具有高度并行性和专用硬件乘法器和加法器的CPU设计，芯片性能大大提高；程序存储器和数据存储器是相互独立的存储器，每个存储器独立编址，独立访问。本系统中设置了16路数据总线，32路地址总线，其余的为控制总线。

　　②串并数据转换采用的芯片为TLl6C752B，此芯片有两个串口控制器，控制器A和控制器B。D00到D07为8位数据总线，RXA和TXA与RXB和TXB分别为A口与B口的数据发送端口和数据接收端口。CSA和CSB分别为A口和B口的片选端口。

　　③RS232电平转换电路，采用的电平转换芯片为MAX3160它把3．3V的TTL电平转换为RS232电平。

　　2．3 ARM显示电路的设计

　　三星公司开发的 S3C2440A是一款以 ARM920T为内核的嵌入式微处理器，它的最高工作频率达433MHz，内含3通道的异步串行口，USB主、从单元设备接口，摄像头接口，触摸LCD／TFT控制器等众多片上外设接口。LCD屏TD035STED2为3．5英寸，屏幕分辨率为320×240，能提供262K中色彩。

　　2．4 PCB设计

　　PCB设计采用的设计软件为Protel99，PCB设计的关键是：模拟电路部分要具有很好的抗干扰能力和高可靠性。提高电路的抗干扰能力的方法有：①元器件布局要合理；②布线要合理；③覆铜要合理；④金属壳接地屏蔽等。

　　3 实验结果分析

　　在完成电路系统设计的基础上，进行激光粒度仪实验。在相同环境、相同采集电路、相同Mie算法条件下，分别用标准P4台式机和DSP+ARM电路进行实验。实验样品采用满足R-R单峰分布的粒径范围为O．1～100μm的碳酸钙。

　　以上两种方式分别连续20次测试，相对于标准样品，实测d50误差在±3％，d10和d90误差在±5％之内，重复精度在±3％以内，说明采集精度达到了仪器标准。实验验证，此系统设计方案比标准P4机运算至少快10s。

　　4 结束语

　　本文将DSP的高速处理能力和ARM得管理能力结合起来，使整个系统在结构上获得最大的灵活性。高性能DSP可以满足运算性能方面的需要，而ARM的可控性。可以解决触摸显示采集结果。同时减小了仪器体积，提高了运算速度。

来源：现代电子技术