基于新型信号源的微波车流量检测器设计

摘要

A new method of design signal source and an integrated design of microwave traffic flow system are brought for the request of microwave traffic flow detection. Compared with the way of concocting transmit signal using only VCO, use Nios Ⅱ processor, DDS and VCO has better linearity and stabilization for emitted wave. Field Programmable Gate Array (FPGA) is used to control microwave transmit-receive board, A/D acquisition and data transmission circuit. For the transforming data, the design uses the technology of USB2. 0 so that the system can oommunicate with computer. It is more convenient to later data analysis and data process. Experimental results show that the system has advantages of stability, integrality data acquisition, anti-jamming.%针对微波车流量检测要求,提出了一种新型信号源设计方法和一套完整的微波车流量检测方案.相比于单独使用VCO产生发射信号,NiosⅡ处理器、DDS、VCO结合起来的信号源设计方法提高了发射波形的线性度和稳定性.利用现场可编程门阵列(FPGA)实现对微波收发板、A/D采集模块、数据传输电路的逻辑控制；在传输方式上,使用USB2.0技术传输数据,实现系统与主机的通信,使后续的数据分析和处理更加方便.实验结果表明,该系统性能稳定、采集的数据完整、抗干扰效果好.