3
$\begingroup$

I am looking for an RF chip that offers a set of bit-rates similar to the PHY bit-rates used in IEEE 802.11 (144 Mbps-900Mbps in 2.4/5GHz bands). I want to embed it on board with a processor with my own firmware. I wish to write my own MAC layer.

To be clear, I went to be able to write a simple program that selects a modulation, frequency and tx power, then loads a raw payload (based on some logic) and transmit. On the receiver end, similarly, there is a program to set a certain modulation/frequency and begin listening. An interrupt is fired at the beginning of receiving a frame. I have been looking everywhere on Digikey, RF Components, Mouser etc. but I do not see any chip that has a clear indication in its datasheet that it allows raw tx/rx. Any idea of any chip that does that?

This is a common feature in IoT chips like AT86RF215. There are 31 different 802.15.4 modulations including OFDM. But I am struggling to find a chip that shows explicitly in datasheet how a specific modulation is selected like the IoT AT86RF215 chip.

I know this can be done with SDR in a USRP. But I am looking for an existing off-the-shelf module.

Improve this question
$\endgroup$
4
  • 1
    $\begingroup$ There's indeed a lot of IEEE802.11 standards, some aren't even RF but infrared! But if you buy a wifi chip today, it'll only do OFDM, full stop, honestly. See my discussion to your question on EE.SE here on how configurable you'll end up being. $\endgroup$
    – Marcus Müller
    Commented Nov 9, 2022 at 16:37
  • 1
    $\begingroup$ I thought just saying the word "802.11" meant you were specifying a specify MAC layer? $\endgroup$
    – Duston
    Commented Nov 10, 2022 at 13:34
  • $\begingroup$ @Duston well, the IEEE802.11 standard defines both a set of PHYs as well as the MAC layer. Some PHYs are basic, others are optional. But it is all treated as the 80211 standard. I wish to only use the PHYs and build my own MAC layer on top of them (I understand it is very unsual). But I have failed to find any chip that opens the PHY layer for programming directly with a proper manual (like I want set a modulation/MCS, frequency, and transmit a raw frame). $\endgroup$
    – user1933458
    Commented Nov 11, 2022 at 10:40
  • $\begingroup$ And I don’t want to put a downer on everything, but I’m pretty sure this is off-topic on this site. Since it hadn’t yet collected any close votes, I’ll leave it for now. $\endgroup$
    – Scott Earle ♦
    Commented Dec 8, 2022 at 13:31

1 Answer 1

Reset to default
4
$\begingroup$

"Wi-Fi" is a trademark referring to the 802.11 family and has layer2 definitionally baked in.

If you want to roll your own layer2, you specifically do NOT want WiFi or 802.11 family chips.

You may have luck finding what you're looking for by searching for "single chip transceiver."

FWIW this seems like an example of the XY Problem, where you're asking about your attempted solution rather than your actual problem. Perhaps you would consider backing up and sharing what you're trying to accomplish with this solution?

Improve this answer
$\endgroup$
2
  • 1
    $\begingroup$ thank you so much for this clarification. I definitely learned something. I believe you are right. I have re-phrased the question above. Maybe this will make more sense? $\endgroup$
    – user1933458
    Commented Dec 8, 2022 at 8:31
  • $\begingroup$ glad it helps! You may have luck finding what you're looking for by searching for "single chip transceiver" or taking a look at what single chip products might be in use for existing ham radio products (packet radio/AX.25/raspberry pi, modules/etc.) $\endgroup$
    – webmarc
    Commented Dec 8, 2022 at 13:21

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .