A pre-certified module brings its own FCC grant for the transmitter. Your finished product still has to comply with FCC rules before you can sell it in the US. The module grant covers the radio. You cover the rest: the host’s digital emissions, the label, the manual, and evidence that the module still behaves as certified once it sits in your enclosure.
Here is what an OEM does for a product built on a modular-approved module, and when the grant stops being enough. For the earlier decision of module versus chip-down, see Advantages of Pre-Certified Wi-Fi and Bluetooth Modules.
Two Paths at a Glance
| Host with a modular-approved module | Chip-down radio | |
|---|---|---|
| Transmitter authorization | Module’s existing FCC ID | New FCC ID in your name, through a TCB |
| Intentional radiator tests (Part 15C, 15E) | Not repeated if you stay inside the grant | Full test campaign |
| Host digital emissions (Part 15B) | Required | Required |
| Product label | “Contains FCC ID” plus the module’s ID | Your own FCC ID |
| Antenna and layout freedom | Limited by the grant | Yours, backed by your own test report |
Step 1: Read the Module Grant
Look up the module’s FCC ID in the FCC database and read the grant and test reports. Check three things.
- Single or limited modular approval. A single modular approval can go in any host that follows the integration instructions. A limited modular approval (LMA) carries conditions, such as a specific host, a required layout, or grantee sign-off for each host.
- Antennas. The grant lists the antennas tested, by type and peak gain. You can use the same type at equal or lower gain.
- RF exposure conditions. Most modular grants assume at least 20 cm between the antenna and people. A handheld or body-worn product falls outside that.
Step 2: Follow the Integration Instructions
47 CFR 15.212 sets the conditions for modular approval, and FCC KDB 996369 sets what the module maker must tell the host maker. The module’s integration guide spells out the antenna, any reference trace or feed-line layout, keep-out areas and supply requirements. Treat those as part of the grant. A PCB trace antenna under a ground pour or against a metal enclosure wall no longer matches what was tested.
On a hosted module, host software matters too. The driver, firmware and calibration files loaded at boot set channels and transmit power. Ship the configuration the module was certified with, and do not give end users a way to change country code or power limits.
Step 3: Check Co-Location and RF Exposure
If the product has more than one transmitter, such as Wi-Fi plus a cellular modem, and they can transmit at the same time, you need a simultaneous-transmission and RF exposure evaluation. Two certified modules do not automatically make a compliant pair. Depending on antenna spacing and power, the result can require a permissive change or a new filing.
Step 4: Test the Host as an Unintentional Radiator
The processor, memory, clocks and switching supplies in your product are a digital device under Part 15 Subpart B. The module grant does not cover them. Pick the class first.
- Class A: commercial and industrial use only.
- Class B: anything marketed for residential use. Tighter limits.
The tests are radiated emissions, from 30 MHz up to a frequency set by the highest clock in the product, and for mains-powered products, AC power line conducted emissions from 150 kHz to 30 MHz. Most hosts are authorized under Supplier’s Declaration of Conformity (SDoC). The host gets no FCC ID of its own, but you need a US-based responsible party and a compliance information statement shipped with the product.
Run a pre-scan at the first prototype. Fixes after tooling (shielding, filtering, spread-spectrum clocks) cost more than fixes at layout.
Step 5: Verify the Module in the Host
KDB 996369 expects the host maker to confirm the combination still complies. The usual check: with the module transmitting at its certified settings inside the finished product, measure radiated spurious emissions and confirm nothing new appears. Host noise mixing with the transmitter, or an enclosure detuning the antenna, can create emissions the module test never saw.
Step 6: Label and Document
- Put “Contains FCC ID:” or “Contains Transmitter Module FCC ID:” followed by the module’s FCC ID on the product where a user can see it.
- Add the 15.19 compliance statement, and for Class B the 15.105 interference statement, to the label or manual as the rules require.
- Carry the RF exposure and antenna statements from the module’s integration guide into your user manual.
Step 7: Repeat for Canada
ISED follows the same model with different documents.
| FCC | ISED Canada |
|---|---|
| Modular grant, FCC ID | Module certification, IC number |
| Part 15B, digital device | ICES-003, labeled “CAN ICES-003(B)/NMB-003(B)” for Class B |
| Part 15C and 15E, 2.4 and 5 GHz radios | RSS-247 with RSS-Gen |
| RF exposure | RSS-102 |
| “Contains FCC ID” | “Contains IC” |
| Class II permissive change | Permissive change under RSP-100 |
Canadian user notices must be in English and French.
When the Module Grant Is Not Enough
| Change in your design | Typical route |
|---|---|
| Same antenna type, equal or lower gain | No filing |
| Different antenna type, or higher gain | Class II permissive change |
| Antenna within 20 cm of the body | Class II permissive change with RF exposure evaluation, often SAR |
| Simultaneous transmission not covered by the grant | Class II permissive change or new filing |
| Changes to the module hardware | New FCC ID |
Only the grant holder can file a Class II permissive change, so the module vendor has to be involved. If the vendor will not file, the fallback is your own FCC ID, which means paying for the intentional radiator tests the module was supposed to save you.
CEL has filed these for customers. A fleet telematics customer had no room for the standard CMP9010 module at 16.64 x 27.8 mm. CEL proposed the CMP9010-9 stamp module, about 192 mm², paired with a 12 x 4 mm antenna designed for the customer’s host PCB. CEL measured peak gain and TRP, then obtained a Class II permissive change, so the customer avoided a full certification. Details: Optimized Antenna Support Case Study (PDF).
Where CEL Helps
CEL’s Wi-Fi and Bluetooth modules, including the CMP9605, CMP9610, CMP961x and CMP4612, list FCC, IC and CE certification. CEL’s support team offers EMC pre-scans, oversight of EMC testing, and countermeasure design. It also runs RF simulation before layout and TRP testing of the finished product in CEL’s anechoic chamber, to catch antenna and enclosure problems before the lab.
Planning a product around a CEL module? Use the form below and a CEL engineer will follow up.