A Compact Wideband Planar Magic Tee for Monopulse Antenna Array Applications

Design of new wideband waveguide Magic‐T for X‐band applications

“…Compared with the references [7,8,10] that has a maximum isolation of 35 dB and 20 dB RL over 22% bandwidth, the proposed Magic-T isolation is improved at least 5 dB at wideband frequency range 8-12 GHz.…”

“…Moreover 20 dB RL bandwidth of Magic-T ports is proven by both measurement and simulation results up to 36% . This bandwidth enhancement compared with the state-of-the-art structure presented in the literatures [6][7][8][9][10][11] is achieved by using the proposed exponentially metallic cone, conducting multistep L-shaped septum in Port 1 and placement of posts in the second, third, and fourth ports, which is suitable for high-power antenna feed network. 1,6 The comparison between the simulation and measurement results declares good agreement, except some inconsistency that is inevitably caused by fabrication error.…”

“…Magic-T is 40% that is significantly larger than the structures proposed in references [8,9] with 22.2% and 22% of bandwidth, respectively. Due to the importance of 20 dB RL bandwidth in high-power handling application, the proposed Magic-T has 36% of 20 dB RL bandwidth over the 8.15-11.7 GHz, which is significantly higher compared with references [6][7][8][9][10][11]. Above mentioned good features of the proposed Magic-T candidates is for wideband-low loss commercial applications such as monopulse comparator and high-power antenna feed network.…”

“…As the conventional Magic‐T is inherently mismatched, metal posts or stubs can be used to achieve impedance matching. Here, two idea combination, utilizing of off‐centered metallic cone presented in reference [7] and l ‐shaped metallic septum presented in reference [10], are considered to achieve better design performance in the proposed Magic‐T structure. In more details, the metallic exponential cone instead of using stepped one used in reference [7] and the l ‐shaped multistepped septum at Port 1, and some other conducting posts in Ports 2, 3, and 4, are considered in the proposed structure as depicted in Figure 1 with details.…”

“…In reference [9] the folded waveguide Magic‐T was proposed for 8–10 GHz application, which has a return loss (RL) of <−15 dB. The high isolation (>30 dB) and low IL (<0.2 dB) features have been achieved by insertion of an l ‐shaped septum 10 and a metal disc cone 11 inside of Magic‐T waveguides for monopulse feed network. By utilizing dual ridge waveguide orthomode transducer and wideband Magic‐T, a compact wideband 10.5–14.5 GHz feed network was proposed in reference [12], which has a dual polarized sum/difference pattern 12 …”