


{"id":355314,"date":"2024-03-05T05:25:51","date_gmt":"2024-03-05T05:25:51","guid":{"rendered":"\/forum\/forums\/topic\/lumerical-interconnect-fiber-pmd-effects\/"},"modified":"2024-03-05T05:25:51","modified_gmt":"2024-03-05T05:25:51","slug":"lumerical-interconnect-fiber-pmd-effects","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/lumerical-interconnect-fiber-pmd-effects\/","title":{"rendered":"Lumerical Interconnect Fiber PMD effects"},"content":{"rendered":"<p>Fiber Model: https:\/\/optics.ansys.com\/hc\/en-us\/articles\/360036108194-Optical-Fiber-FIBER-INTERCONNECT-Element<\/p>\n<p>I have a question regarding PMD effects on fiber model, in my simulation the chromatic dispersion is diabled (D=0 &amp; S=0), fiber length 9 Km. <\/p>\n<p>First: according to the model the user should enter differential group delay &amp; PMD coeff.&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/03\/05-03-2024-1709615403-mceclip0.png\"><\/p>\n<p>However, according to the first reference in the model &#8220;&ldquo;Nonlinear Fiber Optics&#8221;, if I understand correctly then these two parameters are linked through the following equation:&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/03\/05-03-2024-1709615542-mceclip1.png\"><\/p>\n<p>It is not clear to me how to use the model using these two parameters at all, according to &#8221; Modeling and compensation of polarization effects in fiber-optic communication systems&#8221; the delay per each section in the fiber should be calculated directly using the D parameter and the section length, so why do we need an additional parameter as written in the link?&nbsp;<\/p>\n<p>To illustrate my point, The following simulation is for a 9km length fiber and will make it two sections only (4.5km with zero sigma in length) using the following exaggerated numbers for differential group delay (3.3e-14) and pmd coefficient (3.3e-14) just for illustation, the following pulse response result (absolute electric field) is obtained at the output of the fiber:&nbsp;<br \/><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/03\/05-03-2024-1709616036-mceclip2.png\"><\/p>\n<p>I was expecting something different, at the output of the first section of the fiber, there should be two pulses (slow-axis and fast-axis pulses) each of these pulse will couple again into the second section producing the all combination ( slow-slow, fast-slow, fast-fast, slow-fast), so I was expecting something like this:&nbsp;<br \/><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/03\/05-03-2024-1709616268-mceclip3.png\"><\/p>\n<p>Please clarify these points to me.<br \/>Thanks&nbsp;<\/p>\n","protected":false},"template":"","class_list":["post-355314","topic","type-topic","status-closed","hentry","topic-tag-fiber","topic-tag-interconnect","topic-tag-opticalfiber-1","topic-tag-orientation-of-fibers-2","topic-tag-POLARIZATIONCHARACTERISTICS-1","topic-tag-simulation-problems-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["70325","185544"],"_bbp_author_ip":["23.52.43.10"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["317"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["355314"],"_bbp_forum_id":["27833"],"_bbp_engagement":["70325","185544"],"_bbp_voice_count":["2"],"_bbp_reply_count":["3"],"_bbp_last_reply_id":["358027"],"_bbp_last_active_id":["358027"],"_bbp_last_active_time":["2024-03-19 21:57:53"]},"test":"osama3illinois-edu"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/355314","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\/355314\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=355314"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}