{"id":313881,"date":"2023-10-30T07:47:40","date_gmt":"2023-10-30T07:47:40","guid":{"rendered":"\/forum\/forums\/topic\/microstrip-line-is-not-working-as-expected-in-hfss\/"},"modified":"2023-10-30T07:47:40","modified_gmt":"2023-10-30T07:47:40","slug":"microstrip-line-is-not-working-as-expected-in-hfss","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/microstrip-line-is-not-working-as-expected-in-hfss\/","title":{"rendered":"Microstrip line is not working as expected in HFSS"},"content":{"rendered":"<p>Hello,<\/p>\n<p>I am simulating a 50 ohm microstrip line (lambda\/2 at 1.5GHz) with source impedance (lumped port) of 50 ohms and load impedance (lumped port) of 50+1i*50 ohms. First I used the circuit analysis to obtain width and length of 50 ohms line. Since this is lambda\/2 line, the input impedance should be equal to load impedance. I have attached the screenshot below which gave me good result ~50 ohms (to be specific it is 48.69+j*49..32) at 1.5GHZ.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/10\/30-10-2023-1698651195-mceclip2.png\" width=\"466\" height=\"180\"> <img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/10\/30-10-2023-1698651278-mceclip3.png\" width=\"434\" height=\"260\"><\/p>\n<p>However, when I used the same parameter to design it in HFSS model. I could not achieve the exact same values. The real part is off quite a lot. It is ~60 ohms. The screenshot are attached below. Since HFSS model doesnot support zin directly, I calculated Zin as output variables using Zin=Z11-(Z12*Z21)\/(Z22+ZL) where ZL=Port2(Z) which is 50+j*50 when I checked it. Any help will be highly appreciated. For both case substrate is FR4_epoxy(4.4) and 1.67mm thick.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/10\/30-10-2023-1698651568-mceclip4.png\" width=\"386\" height=\"272\"> <img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/10\/30-10-2023-1698652041-blobid0.png\" width=\"613\" height=\"367\"><\/p>\n<p>&nbsp;<\/p>\n<p>Thank you.<\/p>\n","protected":false},"template":"","class_list":["post-313881","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["38174","14222"],"_bbp_author_ip":["168.143.243.14"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["1481"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["313881"],"_bbp_forum_id":["27793"],"_bbp_engagement":["14222","38174"],"_bbp_voice_count":["2"],"_bbp_reply_count":["1"],"_bbp_last_reply_id":["315049"],"_bbp_last_active_id":["315049"],"_bbp_last_active_time":["2023-11-06 13:40:15"]},"test":"sujanaryal2my-unt-edu"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/313881","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\/313881\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=313881"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}