Today there are many modern products that take advantage of wireless transmitter modules that already have been FCC certified by a module manufacturer to demonstrate compliance with FCC regulations.
This brings the advantage of reducing the subsequent requirements for FCC filing when you have used a pre-certified module. But there are limitations for host product manufacturers when it comes to making modifications or changes to the modular transmitter and antenna types that can be used in end products. Eventually host product manufacturers are responsible for following integration guidelines and performing a limited set of transmitter module verification tests to ensure that the end product complies with FCC regulations. Host product manufacturers are also responsible for all additional device authorization and tests for technical requirements not covered by module grant.
If you have a product and you wish to add extra technology to it by means of a pre-certified module, then you need to consider the following labeling rules for FCC.
If you have bought a pre-certified module, then that module must be labeled with its FCC ID directly on it. When the module (for example Wi-Fi or Bluetooth) is integrated inside your host product and becomes a finished product, than the finished product must display the FCC ID of the pre-certified module as explained in the FCC rules in 15.212(a)(1)(vi)(A).
But if a finished product uses an un-approved module and the certification is performed on the finished product, then there will be only one certificate in the name of the finished product. In this case, the finished product will need to be labeled with the FCC ID on the exterior of the product.
In the label or in the manual you should mention the following text for FCC. Also described in FCC 15.19(a)(3); “This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.”
There is further FCC labeling guidance here. And further guidance on modules can be found here.
What they further mention is where its allowed place the label;
The FCC ID must always be accessible when using the product. The placement of the FCC ID must be a physical label on the product, unless an e-label is used. Physical FCC ID labels must be located on the surface of the product, or within a user-accessible nondetachable compartment (such as the battery compartment).
What types are there to modular approval
There are the following types to modular approval:
- Single modular
- Limited single Modular
- Split modular
- Limited split modular
Single modular transmitter:
Demonstrates compliance independent of any host product.
Limited modular transmitter:
Demonstrates compliance when assessed with a specific type of host.
A radio module must meet 8 requirements in order to be certified as a module:
- Radio circuitry must be shielded
- Modulation/data inputs must be buffered
- Module board must have its own power supply regulation
- Module must be certified with specific antenna(s). Antennas must be either permanently attached or use unique connector
- Must be tested stand alone
- Module must have its own label
- Module must comply with all specific rules applicable
- Module must comply with RF exposure requirements
The customer must provide a declaration of how the module meets these criteria when making an application for certification (FCC/ISED).
The filing must include clear instructions on how integrators must integrate the module to continue to comply. (Ref 15.212)
If the module does not meet all 8 requirements? Then it could use an LMA
- Likely because no shield
- Maybe no voltage regulation
In this case with Limited Modular Approval, the module would be authorized with specific hosts in mind.
What about RF Exposure requirements related to the host end product and its use (i.e. handheld, held to the head, worn on the body)?
- A radio module will likely be certified for use in a mobile exposure environment meaning that there will be a restriction that the device can only be 20 cm or further from the operator or nearby persons.
- If the module will be used in an end device that will be handheld or held to the head then it may be necessary to perform a Specific Absorption Rate (SAR) test.
- First determine the application of the end product and then, using the RF power output and operating frequency of the transmitter, evaluate if the device will be exempted from SAR or not.
- A Class II Permissive Change must be used to remove the 20 cm separation restriction.
What about Co-location?
- A radio that is approved as a module will usually have a co-location restriction meaning that it cannot be located within 20 cm of another radio transmitter in the product if the two transmitters will transmit simultaneously.
- (example conditions)“The antenna(s) used for this transmitter must not transmit simultaneously with any other antenna or transmitter, except in accordance with FCC multi transmitter product procedures”.
- (example conditions) Always used with “Grantee must provide installation and operating instructions for complying with FCC multi transmitter product procedures”.
- If the radio module is to be co-located with another transmitter the modular approval can be modified to remove the co location restriction through a Class II Permissive Change filing.
- Only one of the co located transmitters needs to have its grant of approval modified.
- If the multi transmitter product complies without modification of the grant, then verification and Class I Change (no filing) can be used.
- Additional testing to show that the interaction of the multiple modules complies with the technical requirements.
So who is responsible for compliance?
- The certificate holder is always responsible for compliance of the module.
- The manufacturer is always responsible for compliance and labeling of the end product.
- Often preferable to have the original certificate holder update their grant through Class II permissive change (C2PC).
- Can always take control your self through Change in ID (multi list) and then do your C2PC.
Other option for the integrator is using a new FCC ID for the host + module. If the module’s FCC ID will not be displayed on the host system, then the complete finished FCC ID takes precedence over the module FCC ID. In this instance, the test data taken for the module cannot be applied to the host system and the module effectively becomes a component in the system. A similar situation occurs when the transmitter does not have modular approval and is integrated into a host system. The resulting product is required to have a new FCC ID assigned (it cannot be the transmitter FCC ID), and any data taken during the certification of the transmitter is not valid for the host system.
When multiple transmitters are incorporated within a single host, the transmitters are considered collocated. In order for the host to be certified, both of the transmitters must have grants that allow for collocation. If a transmitter is being employed and its grant does not allow for collocation, the manufacturer may ask the grantee to file a Class II permissive change. The manufacturer may also file for a new FCC ID or a change in ID.
So there are two paths to take regarding what to do with module integration from the perspective of the integrator or host manufacturer.
Further FCC Basics to keep in mind can be found here. And more on transmitter modular approval here.