Need Cellular Certification / EMI Expert

We are a hardware company and we designed a rugged diagnostic tool built around an Intel Core i5 COM/conga module with an integrated 5G cellular modem. We are currently in cellular certification and stuck due to EMI-related issues. We already have inventory of circuit boards, so our strong preference is to salvage the existing design via mitigation and test strategy. However, we are open to a board redesign if absolutely required.
We’re looking for an expert who has hands-on experience with carrier certification (Verizon strongly preferred) and/or deep EMI/EMC debugging experience on embedded compute platforms with high-speed interfaces (LTE/5G, PCIe/USB, DDR, power supplies, etc.)

Goals
Identify likely sources/root causes of the EMI failures impacting certification.
Provide a clear, actionable mitigation plan to get the current design to pass (filters, shielding, layout fixes that can be done with ECOs/rework, grounding changes, enclosure changes, cable management, ferrites, power conditioning, etc.).
Support our team through pre-scan troubleshooting and re-test strategy to maximize pass probability.
If salvage is not feasible, propose a minimal-risk redesign plan (layout constraints, stackup, partitioning, RF keepouts, power tree changes, shielding approach), and optionally support a redesign review.

Scope of Work
Review documentation: schematics, PCB layout files, stack-up, BOM, modem integration notes, enclosure/mechanical drawings, cables/harnessing, grounding scheme.
Review test reports / lab notes from Verizon certification attempts and any pre-scan data.
Conduct a structured EMI root-cause assessment:
Suspected radiators (DC/DC converters, clocks, high-speed lanes, display interfaces, USB, Ethernet, antenna/cable coupling, enclosure seams, ground bounce, etc.)
Identify which mitigations are most likely to move the needle fastest.
Recommend specific changes ranked by impact vs. effort:
Reworkable fixes for existing boards (component swaps, add-on shielding cans, copper tape/gaskets, ferrites, filters, common-mode chokes, stitching, firmware changes like spread-spectrum clocking, power sequencing, etc.)
Any required enclosure/cable changes to reduce emissions/coupling
Join calls with our lab/cert partner, help interpret results, and iterate quickly.

What We Will Provide
Full hardware package: physical products, schematics, layout exports, BOM, stackup, mechanical CAD, photos, modem module details, antenna details, and Verizon/cert feedback.
Access to engineering team for quick Q&A and decision-making.
Willingness to run targeted experiments and rework a subset of boards for validation.

Required Experience
Proven EMI/EMC troubleshooting experience on complex embedded products (compute + cellular modem).
Familiarity with carrier certification processes (Verizon preferred).
Ability to give specific recommendations (not generic “add ferrites everywhere” guidance).
Comfortable working with tight timelines and iterative testing.
Nice-to-Have
Experience with 5G/LTE modem integration, antenna/ground/cable coupling issues.
Experience with rugged handheld/tablet-style enclosures.
Experience with pre-scan labs and on-site debug (if needed).
Deliverables
Written findings + prioritized mitigation plan.
Suggested rework/ECO steps for existing boards (with part suggestions where applicable).
Test plan for validation and re-submission strategy.
Design review feedback if a redesign is needed.

Proposal Requirements
Please include:
2–3 examples of similar EMI/EMC or carrier certification saves you’ve led.
Your approach to diagnosing root cause quickly.
Availability over the next 2–3 weeks.
Hourly rate or fixed-price suggestion.

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