3G通信带通滤波器设计及优化

Design and optimization of band-pass filter used in 3G communications

为了消除城市地铁线路中其他频段信号对移动信号的干扰,设计了以2GHz为中心频率,带宽为260MHz的带通滤波器.利用隐式空间映射法在HFSS和ADS中分别建立滤波器的精确模型和粗糙模型设计优化平行耦合带通滤波器.滤波器在1.85GHz到2.15GHz内插入损耗小于3dB,在频率小于1.75GHz、大于2.3GHz的带宽带外抑制大于20dB,并验证了隐式空间映射算法的可行性,降低了设计成本.

A parallel-coupled band-pass filter with 2 GHz center frequency and bandwidth of 260 MHz was presented for eliminating the interference of other signals to the mobile signal in subway lines.The implicit space mapping method was used in the design of the parallel-coupled band-pass filter and its optimization.The software HFSS and ADS were respectively applied in the establishment of the fine model and the coarse model of the filter.The insertion loss of the filter was less than 3 dB within 1.85 GHz to 2.15 GHz.The out-of-band rejection was greater than 20 dB when the stopband extended below 1.75 GHz and above 2.3 GHz.During the design of the filter,the implicit space mapping algorithm was verified to reduce the design costs.