{"id":460135,"date":"2026-06-20T23:09:10","date_gmt":"2026-06-20T23:09:10","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/question-about-hfss-solution-frequency\/"},"modified":"2026-06-20T23:09:10","modified_gmt":"2026-06-20T23:09:10","slug":"question-about-hfss-solution-frequency","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/question-about-hfss-solution-frequency\/","title":{"rendered":"Question about HFSS solution frequency"},"content":{"rendered":"<p>&lt;p&gt;Hi,&lt;br&gt;&lt;br&gt;I am simulating an antenna in HFSS and looking at the impedance plots. When I set my solution frequency to 60MHz and above, I get the following plot:&lt;\/p&gt;&lt;p&gt;&lt;strong id=&#8221;docs-internal-guid-a96ad8d7-7fff-4c75-5817-e90ca25a8f36&#8243;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/06\/20-06-2026-1781996744-blobid0.png\" width=\"606\" height=\"231\" \/><\/strong>&lt;\/p&gt;&lt;p&gt;However, when I set the solution frequency to 50MHz, I get the following:&lt;\/p&gt;&lt;p&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/06\/20-06-2026-1781996790-mceclip0.png\" width=\"607\" height=\"231\" \/>&lt;\/p&gt;&lt;p&gt;Where did the spike at 50MHz go? What is causing it?&nbsp;&lt;br&gt;PS: I am also using a radiation auto-open region.&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-460135","topic","type-topic","status-publish","hentry","topic-tag-ansys-hfss","topic-tag-antenna-design","topic-tag-impedance-plot-1","topic-tag-solution-frequency-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27793"],"_bbp_topic_id":["460135"],"_bbp_subscription":["501109","15859"],"_bbp_author_ip":["128.194.2.161"],"_bbp_last_reply_id":["460148"],"_bbp_last_active_id":["460148"],"_bbp_last_active_time":["2026-06-21 23:45:18"],"_bbp_reply_count":["1"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["501109","15859"],"_btv_view_count":["58"],"_bbp_topic_status":["unanswered"]},"test":"16e00b28dd2f3b553cd5fa1049ef3b9c4c583265"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/460135","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\/460135\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=460135"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}