摘要：随着社会经济不断发展，百姓生活水平不断提升，对出行交通工具的要求随之提高，进而私家车数量不断攀升，导致汽车尾气污染日趋严重。

　　　尾气排放检测是确保机动车尾气排放是否达标的重要方式和保障，为改善人们生活品质有重大意义。由于汽车位置的不确定性，不可能通过有线的方式实现远程监测。当前的汽车检测手段都是在规定的时间内，在固定的地点实施检测，对人们生活带来不便，并且都是在汽车排放后进行检测，也不利于及时发现高排放车辆。本文设计汽车排放实时监控系统，由KWP2000诊断协议获取排放检测系统信息，并重点分析初始化过程、时序控制和故障诊断，从而实现较为完整的基于K线的通讯网络。完成对数据采集后，通过GPRS数据传输技术将发动机信息发送到后台处理。本文采用的是嵌入有TCP/IP协议栈的SIM300C模块，其传输速率快、价格合理，适合应用在车载系统中。后台对发动机信息处理后，通过LCD液晶显示屏显示出来，让驾驶员与监测人员能直观的了解汽车发动机状况，达到对汽车实时监测的要求。本次汽车排放实时监控系统的设计弥补了人工检测技术的不足，并且实现了实时监测车辆排放信息，在以后的汽车排放检测中具有较高的实用价值。

关键字：尾气排放  KWP2000  GPRS  实时监测

ABSTRACT：With the continuous development of social economy, people life level increasing, the travel requirements increased, the number of private cars and rising, resulting in automobile exhaust pollution is becoming more and more serious.

　　　Exhaust emission testing is to ensure that the important way and guarantee whether motor vehicle exhaust emission standards, to improve people's quality of life is of great significance. Because the vehicle position uncertainty, impossible to realize remote monitoring through the wired way. Vehicle detection methods are currently in a specified period of time, the implementation of detection in fixed locations, bring inconvenience to people's life, and were detected in the vehicle emissions, is not conducive to the timely detection of high emission vehicles. Real-time monitoring system design of automobile in this paper emissions, diagnosed by KWP2000 protocol to obtain emission detection system information, and focuses on the analysis of the initialization process, timing control and fault diagnosis, in order to achieve a more complete based on the K-line communication network. To complete the data acquisition, the engine information is sent to the background processing through the GPRS data transmission technology. In this paper, using the SIM300C module embedded TCP\/IP protocol stack, the transmission speed, reasonable price, suitable for application in vehicle system. The background of the engine to the information processing, through the LCD display screen, so that the driver and monitoring personnel can clearly understand the situation of automobile engine, vehicle real-time monitoring requirements. Design of real-time monitoring system of the automobile emission makes up the shortage of artificial detection technology, and realizes real-time monitoring of vehicle emissions information, vehicle emissions detection has higher later in the practical value.

Keywords: exhaust emissions；KWP2000；GPRS；real-time monitoring

　　　不断增加的汽车数量迫使我们不得不研发更加便捷高效的检测方法，以解决好尾气污染带来的严重问题。当前的检测方式都是在规定时间规定地点对汽车进行检测，对行驶过程中车辆状况无法监测，也是目前检测技术所遇到的难点。但随着技术的发展，也研发出了一些能够车载检测的新技术。如：PEMS车载尾气检测设备、OBD车载诊断系统，对检测尾气排放起到了较大控制效果。本次汽车尾气实时监控系统设计，旨在解决对汽车进行实时监控，掌握汽车任何时候的运转情况，从而能实时监测到汽车排放状况，及时处理汽车故障，以减少汽车排放对环境的污染。

　　　为防止汽车排放对大气环境的破坏，有必要对汽车排放实时监控，开发便捷随车检测技术。本文研究汽车排放实时监控系统的设计，旨在解决对排放实时监控，弥补现有监控系统的不足，解决时间和空间的局限性，并且能控制机动车污染从“末端治理”到“源头控制”的转变，有效控制汽车排放。此次设计任务要求完成对发动机排放信息访问，传输到后台监控系统显示，实现汽车排放的实时监控。该系统的研究能增加了检测系统的可靠性、便捷性和实时性，让环境监察部门能随时了解行驶过程中车辆的排放状况。弥补了人工检测技术的不足，并且实现了实时监测车辆排放信息，在以后的汽车排放检测中具有较高的实用价值。