{"id":38549,"date":"2026-11-06T19:50:41","date_gmt":"2026-11-06T11:50:41","guid":{"rendered":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/"},"modified":"2026-11-06T19:50:41","modified_gmt":"2026-11-06T11:50:41","slug":"pcb-plane-cavity-resonance","status":"publish","type":"post","link":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/","title":{"rendered":"PCB Plane Cavity Resonance: Estimate the First Mode"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_89 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#What_resonates_between_the_planes\" >What resonates between the planes<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#Which_rectangle_to_measure\" >Which rectangle to measure<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#Parameters_for_a_first_estimate\" >Parameters for a first estimate<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#How_to_calculate_the_first_two_modes\" >How to calculate the first two modes<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#Cavity_modes_vs_capacitor_antiresonance_vs_fixture_effects\" >Cavity modes vs capacitor antiresonance vs fixture effects<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#Why_plane_spacing_still_matters\" >Why plane spacing still matters<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#Why_the_probe_location_changes_what_you_see\" >Why the probe location changes what you see<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#When_the_simple_estimate_stops_being_useful\" >When the simple estimate stops being useful<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#How_to_compare_an_unpopulated_and_assembled_board\" >How to compare an unpopulated and assembled board<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#How_to_decide_whether_the_mode_matters\" >How to decide whether the mode matters<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#What_to_change_after_identifying_the_mechanism\" >What to change after identifying the mechanism<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#What_to_record_for_the_next_design_revision\" >What to record for the next design revision<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#FAQ\" >FAQ<\/a><\/li><\/ul><\/nav><\/div>\n<div class=\"yzp-no-index\"><\/div><p>A power plane and its neighboring ground plane can behave like a resonant cavity. For a uniform rectangular overlap, a first screening estimate uses the electrical length of that overlap: a larger plane or higher dielectric constant moves the first mode lower. Use the estimate to identify a frequency band to investigate, not to predict the exact impedance or emissions of the assembled board.<\/p>\n<figure><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2026\/11\/plane-cavity-vna-bench.jpg\" width=\"1120\" height=\"630\" style=\"max-width:100%;height:auto\" alt=\"PCB test coupon beside a vector network analyzer\"><figcaption>PCB test coupon beside a vector network analyzer. AI-generated illustration, not a measurement or production record.<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"What_resonates_between_the_planes\"><\/span>What resonates between the planes<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A changing current can launch electromagnetic energy between two copper planes separated by dielectric. At certain frequencies the fields can form standing-wave patterns. A mode is one such pattern; it is not the same as saying that every point on the board has a large voltage at that frequency.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Which_rectangle_to_measure\"><\/span>Which rectangle to measure<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Use the overlap of the two planes involved, not automatically the finished board outline. A rail that occupies one portion of a larger ground plane has a smaller relevant outline. A narrow neck, cutout or divided rail can invalidate the simple rectangular approximation.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Parameters_for_a_first_estimate\"><\/span>Parameters for a first estimate<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Use consistent units and document what each dimension represents.<\/p>\n<figure class=\"wp-block-table\">\n<table>\n<tbody>\n<tr>\n<td><strong>Input<\/strong><\/td>\n<td><strong>Example only<\/strong><\/td>\n<td><strong>How to use it<\/strong><\/td>\n<\/tr>\n<tr>\n<td>Overlap length a<\/td>\n<td>100 mm<\/td>\n<td>Longer in-plane dimension<\/td>\n<\/tr>\n<tr>\n<td>Overlap width b<\/td>\n<td>60 mm<\/td>\n<td>Shorter in-plane dimension<\/td>\n<\/tr>\n<tr>\n<td>Relative permittivity<\/td>\n<td>4.0<\/td>\n<td>Illustrative uniform value for the plane dielectric<\/td>\n<\/tr>\n<tr>\n<td>Plane spacing<\/td>\n<td>Record actual spacing in mm<\/td>\n<td>Influences impedance and coupling; not a term in this simple in-plane frequency estimate<\/td>\n<\/tr>\n<tr>\n<td>Mode indices m and n<\/td>\n<td>(1,0), (0,1)<\/td>\n<td>Number of half-wave variations along each axis under the model<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<h2><span class=\"ez-toc-section\" id=\"How_to_calculate_the_first_two_modes\"><\/span>How to calculate the first two modes<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>For the idealized rectangular cavity, use f(m,n) \u2248 c divided by twice the square root of relative permittivity, multiplied by the square root of [(m\/a)\u00b2 + (n\/b)\u00b2]. Use meters and c \u2248 3 \u00d7 10\u2078 m\/s. With the sample geometry, (1,0) is about 0.75 GHz and (0,1) about 1.25 GHz. The first nonzero estimate is lower along the longer direction. <a href=\"https:\/\/arxiv.org\/abs\/1008.2602\">Mattey, Edwards and Hood&#8217;s cavity study<\/a> compares cavity estimates with field simulation; their refined estimate includes a small fringing correction omitted in this screening calculation.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cavity_modes_vs_capacitor_antiresonance_vs_fixture_effects\"><\/span>Cavity modes vs capacitor antiresonance vs fixture effects<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A peak is a clue, not a diagnosis. Compare what changes the peak before changing the board.<\/p>\n<figure class=\"wp-block-table\">\n<table>\n<tbody>\n<tr>\n<td><strong>Candidate<\/strong><\/td>\n<td><strong>What it follows<\/strong><\/td>\n<td><strong>Useful check<\/strong><\/td>\n<\/tr>\n<tr>\n<td>Plane cavity mode<\/td>\n<td>Overlap geometry, dielectric and position<\/td>\n<td>Compare predicted bands and probe at multiple locations<\/td>\n<\/tr>\n<tr>\n<td>PDN antiresonance<\/td>\n<td>Interaction between capacitance and inductance in the mounted network<\/td>\n<td>Compare with a validated model or controlled population change<\/td>\n<\/tr>\n<tr>\n<td>Fixture artifact<\/td>\n<td>Launch, cable, calibration or probe geometry<\/td>\n<td>Repeat with stable connections and inspect the fixture response<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Why_plane_spacing_still_matters\"><\/span>Why plane spacing still matters<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Moving planes closer changes their distributed capacitance and impedance even when the idealized first-mode frequency expression does not contain their separation. Do not conclude that spacing is unimportant. Real dielectric structures, losses and boundary conditions can change how a resonance appears.<\/p>\n<figure><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2026\/11\/plane-cavity-test-coupon.jpg\" width=\"1120\" height=\"630\" style=\"max-width:100%;height:auto\" alt=\"PCB test coupon with coaxial measurement launches\"><figcaption>PCB test coupon with coaxial measurement launches. AI-generated illustration, not a measurement or production record.<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Why_the_probe_location_changes_what_you_see\"><\/span>Why the probe location changes what you see<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A mode can be weak at one location and strong at another. If the predicted band appears quiet at a single port, try a second point chosen to couple to a different part of the field pattern. Document the port locations so the comparison can be repeated.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"When_the_simple_estimate_stops_being_useful\"><\/span>When the simple estimate stops being useful<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Treat irregular shapes, multiple return planes, heavy segmentation and connected cavities as cases for a model of the actual layout. A rectangle can still identify an order of magnitude, but a precise numerical result would imply geometry the model does not contain.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_compare_an_unpopulated_and_assembled_board\"><\/span>How to compare an unpopulated and assembled board<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Keep the same reference points and fixture when practical. The unpopulated coupon can help isolate geometry; the populated board adds decoupling, package and regulator interactions. A difference between the traces can be meaningful only when the changed conditions are recorded.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"How_to_decide_whether_the_mode_matters\"><\/span>How to decide whether the mode matters<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Compare the observed response with the frequency content of the excitation and with the requirements at the affected ports. A mode that is not strongly excited may be less significant than a lower-frequency impedance problem. Do not equate a simulated mode with a measured compliance failure.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_to_change_after_identifying_the_mechanism\"><\/span>What to change after identifying the mechanism<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>If the evidence points to the plane geometry, consider a stackup, shape or damping change supported by modeling and measurement. If the peak instead follows capacitor population or fixture changes, address that mechanism first. Review any layout change for return-path and current-delivery consequences.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_to_record_for_the_next_design_revision\"><\/span>What to record for the next design revision<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Save the overlap geometry, dielectric assumptions, estimated mode band, port locations, raw data, populated state and the acceptance requirement. Use this with the <a href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/05\/pcb-power-integrity-2\/\">broader PCB power-integrity workflow<\/a>. For a stackup or test-coupon manufacturing review, contact Best Technology at <a href=\"mailto:sales@bestpcbs.com\">sales@bestpcbs.com<\/a>.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"FAQ\"><\/span>FAQ<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3>Can I use the longest edge of the entire board?<\/h3>\n<p>Only if that dimension represents the active rectangular overlap in the model. A power island can be smaller than the overall board, and nearby splits or necks can make even its bounding rectangle misleading. Identify the two conductors and their overlap first.<\/p>\n<h3>Which dielectric constant should I use?<\/h3>\n<p>Use a documented value appropriate to the actual plane dielectric and the band of interest. For a quick calculation, label an assumed value as such. When several materials or uncertain geometry are involved, compare a bounded range or use an appropriate field model.<\/p>\n<h3>Is a frequency estimate enough to choose decoupling capacitors?<\/h3>\n<p>No. The calculation estimates where an idealized mode can occur. It does not predict the impedance at a particular device port or the effect of capacitor mounting inductance. Evaluate the actual PDN and verify the relevant band before changing the population.<\/p>\n<h3>Why might I see a different peak on a second port?<\/h3>\n<p>Different locations can couple differently to the same standing-wave pattern, and the two launches may not be identical. Compare the expected mode shapes, port definitions and fixture behavior before concluding that every observed peak represents a different physical resonance in the PCB.<\/p>\n<h3>Can power planes resonate when their DC voltage looks stable?<\/h3>\n<p>Yes. A DC reading shows the average or slow behavior at the instrument&#8217;s measurement point. A resonant response is frequency-dependent and may only be visible with suitable bandwidth and a defined excitation or measurement configuration. Record both when they answer different questions.<\/p>\n<h3>Does a larger board always have a lower cavity mode?<\/h3>\n<p>Not necessarily. The relevant dimension is the electrical length of the participating plane overlap, not simply the product outline. The dielectric and boundaries also matter. Compare like geometry and material assumptions before interpreting the direction of any frequency change between designs.<\/p>\n<h3>Can I identify a cavity mode from emissions alone?<\/h3>\n<p>An emissions peak can indicate a band worth investigating, but it does not isolate the source. Compare near-field or port evidence with geometry and known excitation, and check cables, enclosure and test fixtures before assigning the peak to the plane pair.<\/p>\n<h3>Is the calculated frequency a compliance limit?<\/h3>\n<p>No. It is a screening estimate for a simplified geometry. Compliance criteria depend on the applicable test and product requirements. Use the estimate to choose what to simulate or measure, and keep the resulting evidence separate from the calculation in the qualification report.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.<\/p>\n","protected":false},"author":32827,"featured_media":38547,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[174],"tags":[9162,9161,9100,8249],"class_list":["post-38549","post","type-post","status-publish","format-standard","hentry","category-bestpcb","tag-impedance-measurement","tag-pcb-plane-resonance","tag-pdn","tag-power-integrity"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.4 - aioseo.com -->\n\t<meta name=\"description\" content=\"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"mingling, gong\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.4\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"PCB &amp; MCPCB - EBest PCB - More Technical Details &amp; News on PCB, MCPCB &amp; Ceramic PCB from EBest PCB\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"PCB Plane Cavity Resonance: Estimate the First Mode\" \/>\n\t\t<meta property=\"og:description\" content=\"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/\" \/>\n\t\t<meta property=\"og:image\" content=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/08\/logo.png\" \/>\n\t\t<meta property=\"og:image:secure_url\" content=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/08\/logo.png\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2026-11-06T11:50:41+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2026-11-06T11:50:41+00:00\" \/>\n\t\t<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/Bestpcbs1\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:site\" content=\"@bestpcbs\" \/>\n\t\t<meta name=\"twitter:title\" content=\"PCB Plane Cavity Resonance: Estimate the First Mode\" \/>\n\t\t<meta name=\"twitter:description\" content=\"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.\" \/>\n\t\t<meta name=\"twitter:creator\" content=\"@bestpcbs\" \/>\n\t\t<meta name=\"twitter:image\" content=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2016\/02\/logo.gif\" \/>\n\t\t<script type=\"application\/ld+json\" class=\"aioseo-schema\">\n\t\t\t{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"BlogPosting\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#blogposting\",\"name\":\"PCB Plane Cavity Resonance: Estimate the First Mode\",\"headline\":\"PCB Plane Cavity Resonance: Estimate the First Mode\",\"author\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/author\\\/gong588\\\/#author\"},\"publisher\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#organization\"},\"image\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/11\\\/plane-cavity-vna-bench.jpg\",\"width\":1120,\"height\":630},\"datePublished\":\"2026-11-06T19:50:41+08:00\",\"dateModified\":\"2026-11-06T19:50:41+08:00\",\"inLanguage\":\"en-US\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#webpage\"},\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#webpage\"},\"articleSection\":\"bestpcb, Impedance Measurement, PCB Plane Resonance, PDN, Power Integrity\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#breadcrumblist\",\"itemListElement\":[{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#listItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/category\\\/bestpcb\\\/#listItem\",\"name\":\"bestpcb\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/category\\\/bestpcb\\\/#listItem\",\"position\":2,\"name\":\"bestpcb\",\"item\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/category\\\/bestpcb\\\/\",\"nextItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#listItem\",\"name\":\"PCB Plane Cavity Resonance: Estimate the First Mode\"},\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#listItem\",\"name\":\"Home\"}},{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#listItem\",\"position\":3,\"name\":\"PCB Plane Cavity Resonance: Estimate the First Mode\",\"previousItem\":{\"@type\":\"ListItem\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/category\\\/bestpcb\\\/#listItem\",\"name\":\"bestpcb\"}}]},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#organization\",\"name\":\"PCB & MCPCB - Best Technology\",\"description\":\"More Technical Details & News on PCB, MCPCB & Ceramic PCB from EBest PCB\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/\",\"telephone\":\"+8675529091601\",\"logo\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/08\\\/logo.png\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#organizationLogo\"},\"image\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#organizationLogo\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/Bestpcbs1\",\"https:\\\/\\\/twitter.com\\\/bestpcbs\",\"https:\\\/\\\/www.youtube.com\\\/channel\\\/UCJsTR02i6mtLFnBBNC_i4bQ\\\/featured\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/best-pcb-technology\"]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/author\\\/gong588\\\/#author\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/author\\\/gong588\\\/\",\"name\":\"mingling, gong\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#authorImage\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/37717913504b7ea1df97ec73d58a7bcc?s=96&d=mm&r=g\",\"width\":96,\"height\":96,\"caption\":\"mingling, gong\"}},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#webpage\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/\",\"name\":\"PCB Plane Cavity Resonance: Estimate the First Mode\",\"description\":\"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.\",\"inLanguage\":\"en-US\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#website\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#breadcrumblist\"},\"author\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/author\\\/gong588\\\/#author\"},\"creator\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/author\\\/gong588\\\/#author\"},\"image\":{\"@type\":\"ImageObject\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/wp-content\\\/uploads\\\/2026\\\/11\\\/plane-cavity-vna-bench.jpg\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#mainImage\",\"width\":1120,\"height\":630},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/2026\\\/11\\\/pcb-plane-cavity-resonance\\\/#mainImage\"},\"datePublished\":\"2026-11-06T19:50:41+08:00\",\"dateModified\":\"2026-11-06T19:50:41+08:00\"},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/\",\"name\":\"PCB & MCPCB - Best Technology\",\"description\":\"More Technical Details & News on PCB, MCPCB & Ceramic PCB from EBest PCB\",\"inLanguage\":\"en-US\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.bestpcbs.com\\\/blog\\\/#organization\"}}]}\n\t\t<\/script>\n\t\t<!-- All in One SEO -->\n\n","aioseo_head_json":{"title":"PCB Plane Cavity Resonance: Estimate the First Mode","description":"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.","canonical_url":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"BlogPosting","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#blogposting","name":"PCB Plane Cavity Resonance: Estimate the First Mode","headline":"PCB Plane Cavity Resonance: Estimate the First Mode","author":{"@id":"https:\/\/www.bestpcbs.com\/blog\/author\/gong588\/#author"},"publisher":{"@id":"https:\/\/www.bestpcbs.com\/blog\/#organization"},"image":{"@type":"ImageObject","url":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2026\/11\/plane-cavity-vna-bench.jpg","width":1120,"height":630},"datePublished":"2026-11-06T19:50:41+08:00","dateModified":"2026-11-06T19:50:41+08:00","inLanguage":"en-US","mainEntityOfPage":{"@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#webpage"},"isPartOf":{"@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#webpage"},"articleSection":"bestpcb, Impedance Measurement, PCB Plane Resonance, PDN, Power Integrity"},{"@type":"BreadcrumbList","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#breadcrumblist","itemListElement":[{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/#listItem","position":1,"name":"Home","item":"https:\/\/www.bestpcbs.com\/blog\/","nextItem":{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/#listItem","name":"bestpcb"}},{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/#listItem","position":2,"name":"bestpcb","item":"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/","nextItem":{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#listItem","name":"PCB Plane Cavity Resonance: Estimate the First Mode"},"previousItem":{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/#listItem","name":"Home"}},{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#listItem","position":3,"name":"PCB Plane Cavity Resonance: Estimate the First Mode","previousItem":{"@type":"ListItem","@id":"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/#listItem","name":"bestpcb"}}]},{"@type":"Organization","@id":"https:\/\/www.bestpcbs.com\/blog\/#organization","name":"PCB & MCPCB - Best Technology","description":"More Technical Details & News on PCB, MCPCB & Ceramic PCB from EBest PCB","url":"https:\/\/www.bestpcbs.com\/blog\/","telephone":"+8675529091601","logo":{"@type":"ImageObject","url":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/08\/logo.png","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#organizationLogo"},"image":{"@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#organizationLogo"},"sameAs":["https:\/\/www.facebook.com\/Bestpcbs1","https:\/\/twitter.com\/bestpcbs","https:\/\/www.youtube.com\/channel\/UCJsTR02i6mtLFnBBNC_i4bQ\/featured","https:\/\/www.linkedin.com\/company\/best-pcb-technology"]},{"@type":"Person","@id":"https:\/\/www.bestpcbs.com\/blog\/author\/gong588\/#author","url":"https:\/\/www.bestpcbs.com\/blog\/author\/gong588\/","name":"mingling, gong","image":{"@type":"ImageObject","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#authorImage","url":"https:\/\/secure.gravatar.com\/avatar\/37717913504b7ea1df97ec73d58a7bcc?s=96&d=mm&r=g","width":96,"height":96,"caption":"mingling, gong"}},{"@type":"WebPage","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#webpage","url":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/","name":"PCB Plane Cavity Resonance: Estimate the First Mode","description":"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.","inLanguage":"en-US","isPartOf":{"@id":"https:\/\/www.bestpcbs.com\/blog\/#website"},"breadcrumb":{"@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#breadcrumblist"},"author":{"@id":"https:\/\/www.bestpcbs.com\/blog\/author\/gong588\/#author"},"creator":{"@id":"https:\/\/www.bestpcbs.com\/blog\/author\/gong588\/#author"},"image":{"@type":"ImageObject","url":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2026\/11\/plane-cavity-vna-bench.jpg","@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#mainImage","width":1120,"height":630},"primaryImageOfPage":{"@id":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/#mainImage"},"datePublished":"2026-11-06T19:50:41+08:00","dateModified":"2026-11-06T19:50:41+08:00"},{"@type":"WebSite","@id":"https:\/\/www.bestpcbs.com\/blog\/#website","url":"https:\/\/www.bestpcbs.com\/blog\/","name":"PCB & MCPCB - Best Technology","description":"More Technical Details & News on PCB, MCPCB & Ceramic PCB from EBest PCB","inLanguage":"en-US","publisher":{"@id":"https:\/\/www.bestpcbs.com\/blog\/#organization"}}]},"og:locale":"en_US","og:site_name":"PCB &amp; MCPCB - EBest PCB - More Technical Details &amp; News on PCB, MCPCB &amp; Ceramic PCB from EBest PCB","og:type":"article","og:title":"PCB Plane Cavity Resonance: Estimate the First Mode","og:description":"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.","og:url":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/","og:image":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/08\/logo.png","og:image:secure_url":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/08\/logo.png","article:published_time":"2026-11-06T11:50:41+00:00","article:modified_time":"2026-11-06T11:50:41+00:00","article:publisher":"https:\/\/www.facebook.com\/Bestpcbs1","twitter:card":"summary_large_image","twitter:site":"@bestpcbs","twitter:title":"PCB Plane Cavity Resonance: Estimate the First Mode","twitter:description":"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.","twitter:creator":"@bestpcbs","twitter:image":"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2016\/02\/logo.gif"},"aioseo_meta_data":{"post_id":"38549","title":"PCB Plane Cavity Resonance: Estimate the First Mode","description":"Estimate the first PCB plane cavity mode from overlap and dielectric data, then distinguish it from capacitor antiresonance and fixture effects.","keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":"","og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":"default","schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":0,"frequency":"default","local_seo":null,"breadcrumb_settings":null,"limit_modified_date":false,"ai":null,"created":"2026-11-06 11:50:41","updated":"2026-11-06 12:33:16","seo_analyzer_scan_date":null,"focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"aioseo_breadcrumb":"<div class=\"aioseo-breadcrumbs\"><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/www.bestpcbs.com\/blog\/\" title=\"Home\">Home<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">\u00bb<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\t<a href=\"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/\" title=\"bestpcb\">bestpcb<\/a>\n\t\t<\/span><span class=\"aioseo-breadcrumb-separator\">\u00bb<\/span><span class=\"aioseo-breadcrumb\">\n\t\t\tPCB Plane Cavity Resonance: Estimate the First Mode\n\t\t<\/span><\/div>","aioseo_breadcrumb_json":[{"label":"Home","link":"https:\/\/www.bestpcbs.com\/blog\/"},{"label":"bestpcb","link":"https:\/\/www.bestpcbs.com\/blog\/category\/bestpcb\/"},{"label":"PCB Plane Cavity Resonance: Estimate the First Mode","link":"https:\/\/www.bestpcbs.com\/blog\/2026\/11\/pcb-plane-cavity-resonance\/"}],"_links":{"self":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts\/38549","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/users\/32827"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/comments?post=38549"}],"version-history":[{"count":0,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts\/38549\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/media\/38547"}],"wp:attachment":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/media?parent=38549"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/categories?post=38549"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/tags?post=38549"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}