A dual polarized quasi-monostatic simultaneous transmit and receive (STAR) antenna system operating over 2:1 bandwidth with high isolation, co-polarized transmitting (TX)/receiving (RX) radiation, and high TX gain is proposed. The TX antenna is apex matched parabolic reflector illuminated by a coaxial cavity feed. The RX antenna is also coaxial cavity and mounted back-to-back with the TX feed. Thus, the configuration is termed quasi-monostatic. High front-to-back (F/B) ratio of the RX and TX feed antennas and the separation between them ensures high isolation. The fabricated system achieves 61 dB (average) isolation for CP and >38.5 dB for linearly copolarized TX and RX antennas. Moreover, the amplitude and phase imbalances in beam forming network (BFN) have lesser impact than the BFN-based STAR antenna systems. The antenna system operates from 4 to 8 GHz with VSWR <1.8, gain >7 dBic, and >20 dBic for the RX and TX, respectively. Additional techniques to further improve isolation are outlined.

中文翻译：

---

宽带准单稳态同时发射和接收反射面天线

提出了一种双极化准单稳态同步发射和接收 (STAR) 天线系统，该系统在 2:1 带宽上运行，具有高隔离度、共极化发射 (TX)/接收 (RX) 辐射和高 TX 增益。TX 天线是由同轴腔馈电照明的顶点匹配抛物面反射器。RX 天线也是同轴腔体，并与 TX 馈源背靠背安装。因此，该配置被称为准单稳态。RX 和 TX 馈电天线的高前后 (F/B) 比以及它们之间的分离确保了高隔离度。制造的系统实现了 61 dB（平均）的 CP 隔离和 >38.5 dB 的线性共极化 TX 和 RX 天线。此外，波束成形网络 (BFN) 中的幅度和相位不平衡的影响比基于 BFN 的 STAR 天线系统的影响要小。天线系统在 4 至 8 GHz 的频率范围内运行，VSWR <1.8，增益 >7 dBic，RX 和 TX 分别 >20 dBic。概述了进一步改进隔离的其他技术。