高隔离SAW双工器模组的研制

Development of High-Isolation SAW Diplexer Module

为进一步提高LTE B3双工器频段间隔离度,利用系统级封装(SIP)技术设计了一种高隔离声表面波(SAW)双工器模组。该模组由2个SAW双工器和3个耦合器组成,利用TX-RX路径的相位相消及耦合器的隔离度,实现单颗SAW双工器上下行链路间隔离度的提高。采用阻抗元滤波器架构,实现了单颗SAW双工器隔离度达51 dB。采用宽边带状线多层螺旋耦合线结构实现了工作宽带宽、集成小型化的3 dB耦合器。研制的模组测试结果表明,在B3频段内,尺寸为8.0 mm×8.0 mm×2.0 mm,插入损耗小于3.2 dB,回波损耗大于13 dB,隔离度优于65 dB,承受瞬间功率可达34 dBm。

To further improve LTE B3 diplexer interband isolation,a high-isolation SAW duplexer module is designed using SIP technology in this study.The module is composed of two SAW duplexers and three couplers.It applies the phase cancellation of the TX-RX path and the isolation of the couplers to improve the isolation between the uplink and downlink of a single SAW duplexer.An impedance-element filter architecture is used to achieve an isolation degree of 51 dB for the proposed module.A broadside stripline multilayer helical coupler-line architecture is adopted to achieve miniaturized integrated 3 dB couplers with a wide operating bandwidth.The results of the developed module show that in the B3 band,for a SAW duplexer measuring 8.0 mm×8.0 mm×2.0 mm,the insertion loss is less than 3.2 dB,the return loss exceeds 13 dB,and the isolation degree exceeds 65 dB;furthermore,it can withstand instantaneous power levels up to 34 dBm.