Abstract: The CC2420 is chosen as the RF processing and communicating unit of sensor-node.According to the characteristics of CC2420’s RF I/O ports，a PFDA（Printed Folded-Dipole-Antenna） is used.The antenna is fed by a couple of CPS（Coplanar Strip）.After a series of simulations，the antenna’s resonance impedance and length are acquired.The resonance impedance is higher than that of an ordinary CPS，so it is necessary to amend the antenna in order to reduce its resonance properly.The basic impedance-matching circuit has to be amended as well.The performance and correctness of the amended antenna，feeding line，and impedance-matching circuit are simulated and proved.

Key words: sensor-node, Printed Folded-Dipole-Antenna（PFDA）, Coplanar Strip（CPS）, resonance impedance, impedance match, performance of antenna

摘要： 选择了CC2420芯片作为传感器节点的射频通信与处理模块。根据CC2420射频I/O端口的特点与要求，选择的天线是印制折合偶极天线，并采用共面带状线对其馈电。通过仿真找到天线的谐振阻抗与谐振长度，谐振阻抗高于一般共面带状线的特性阻抗，因此对天线进行改进以适当降低其谐振阻抗，同时对基本匹配电路进行改进。对改进后的天线、馈线及阻抗匹配电路的正确性及性能进行了仿真与验证。

关键词: 传感器节点, 印制折合偶极天线, 共面带状线, 谐振阻抗, 阻抗匹配, 天线性能