


{"id":242580,"date":"2022-11-30T20:41:10","date_gmt":"2022-11-30T20:41:10","guid":{"rendered":"\/forum\/forums\/topic\/single-port-model-circuit-element-on-coax-in-hfss\/"},"modified":"2022-11-30T20:43:04","modified_gmt":"2022-11-30T20:43:04","slug":"single-port-model-circuit-element-on-coax-in-hfss","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/single-port-model-circuit-element-on-coax-in-hfss\/","title":{"rendered":"Single-Port Model\/Circuit Element on Coax in HFSS"},"content":{"rendered":"<p>Greetings,<\/p>\n<p>I have been attempting to use HFSS&#8217;s Single-Port Model feature (covered in Ch 19 of the help manual) in a simulation to represent a complex Circuit Element for a system that I am simulating. However, when I apply this tool to a coaxial port, I have not been getting reasonable behavior, and instead the system is just behaving as an open circuit. I&#8217;ve been able to get a Single-Port Model to work on a microstrip format, so I believe I&#8217;m otherwise using the feature correctly. Is there something I&#8217;m missing in the Circuit Element behavior?<\/p>\n<p>An example coaxial simulation is provided below for reference:<br \/><a class=\"wp-colorbox-image cboxElement\" href=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840327-Coax Circuit Element Example.PNG\"><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840327-Coax Circuit Element Example.PNG\" alt=\"\" width=\"1108\" height=\"439\"><\/a><\/p>\n<p>I&#8217;m feeding the other end with just a simple lumped port. I&#8217;ve simulated this geometry with lumped ports on both ends to make sure the model is valid, so that&#8217;s not the issue.<\/p>\n<p>Here&#8217;s the example s1p file I&#8217;ve used to define the Circuit Element for the Single-Port Model:<\/p>\n<p><a class=\"wp-colorbox-image cboxElement\" href=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840505-HOM Port Model.PNG\"><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840505-HOM Port Model.PNG\" alt=\"\" width=\"567\" height=\"351\"><\/a><\/p>\n<p>Since this is just a simple matched coax line, the S11 of my lumped port should basically just look like that, right? However, instead it just looks like a mostly open circuit. Observe:<\/p>\n<p><a class=\"wp-colorbox-image cboxElement\" href=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840636-Coax Circuit Element Example Output.PNG\"><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/30-11-2022-1669840636-Coax Circuit Element Example Output.PNG\" alt=\"\" width=\"880\" height=\"436\"><\/a><\/p>\n<p>I&#8217;ve also seen that the E-fields at the Circuit Element definition boundary at the end of the coaxial line don&#8217;t conform to the expected TEM distribution (while they do for the feed at the other end), which leads me to believe that there is an extra definition that I need to do.<\/p>\n<p>Any advice or help would be appreciated!<\/p>\n","protected":false},"template":"","class_list":["post-242580","topic","type-topic","status-closed","hentry","topic-tag-hfsslumped_sources-1","topic-tag-ansys-hfss","topic-tag-circuit-elements-1","topic-tag-coaxial-cable-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["269316","28551"],"_bbp_author_ip":["23.44.170.61"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["1955"],"_edit_lock":["1669840892:198852"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["242580"],"_bbp_forum_id":["27793"],"_bbp_engagement":["28551","269316"],"_bbp_voice_count":["2"],"_bbp_reply_count":["3"],"_bbp_last_reply_id":["281655"],"_bbp_last_active_id":["281655"],"_bbp_last_active_time":["2023-04-28 18:21:53"]},"test":"dpieperfnal-gov"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/242580","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/242580\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=242580"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}