According to ARK most Intel wireless adapters support both PCIe and USB for the System Interface Type.
Do they actually support USB as a host interface or is it just a reference to the electromechanical form factor (e.g. Mini PCIe)?
We are not too sure if we understand inquiry. Could you provide us the adapters you saw on ARK with USB?
Looking and comparing some of our adapters on ARK: http://ark.intel.com/compare/59470,59480,84177,66889,75174 ARK | Compare Intel® Products from a chronological perspective taking into consideration the last four years, you can see they are all PCIe or M.2. Let us know if this is what you are looking for.
The Intel Wireless-AC 3160 for example is available as MiniPCIe or M.2. In the ARK database it is stated that the System Interface Type is "PCIe, USB". Both MiniPCIe and M.2 specify a USB bus on their pins. So I'd like to know if the AC-3160 only supports PCIe as the host interface or if I can use USB as well provided I connect the proper pins on the card.
The connector slot for both HMC or M.2 form factors must support both host interface modes (PCIe and USB), since the two of them are required in order to support the features of the wireless adapter. You also need to consider whether your computer is compatible and for this we recommend that you contact the computer manufacturer for such information in order to make sure you will reach your goal.
In my case I am the manufacturer of the target computer. It is an embedded system where using one of the Intel adapters is my primary choice for adding a WiFi extension. For that I need to know if I can use a specifc adapter like the AC-3160 by only using the USB signals of the HMC or M.2 slot without connecting the PCIe signals. If I need PCIe at all I have to look for a different solution by either using a processor with PCIe support or an adapter with native USB support.
If you are a developer and/or OEM, we recommend you to contact your Intel consultant or the nearest Intel Contact Center. Here is the link: http://www.intel.com/p/en_US/support/contactsupport Contact Support and have one of our technicians to submit your request to our pre-sales department for further assistance.