2
$\begingroup$

I want to ask something about the compatibility issue of the sub-1Ghz radio.

If I am using two different RF chips (such as TI's cc1120 and Silicon Labs' si4432; both have FSK modulation), can they communicate with each other?

update 2015-06-12 (more details)

I have read the datasheets (however I am not a professional communication engineer, so I cannot quite understand all the details...).

For example, both cc1120 and si4463 have GFSK modulation, they both support the same frequency range, they both can hop frequency in several tens of us.

Some chip support FEC and digital encoding, but for compatibility's sake, these features can be disabled.

I have searched the internet, however haven't found someone do this kind of experiments. Do you guys know someone who has experiences on this? Thanks.

$\endgroup$
2
  • $\begingroup$ Could you explain what “sub-1GHz” has to do with the question? Why is this a specific category? You tagged with UHF — is the range from 300 MHz to 1000 MHz significant? $\endgroup$
    – Kevin Reid AG6YO
    Jun 10 '15 at 17:38
  • 1
    $\begingroup$ @KevinReidAG6YO There are many proprietary sub-1Ghz chipsets, such as TI cc1120, silicon labs si4463 etc. These chips usually have no specific MAC protocol implemented, so the users need to implement their own protocol (or port existing protocol). However, with regard to 2.4Ghz chipset, most of them contain existing protocols (i.e. the vendor has implemented the standard protocols, such as wifi, zigbee, etc). $\endgroup$
    – jtuki
    Jun 12 '15 at 3:16
1
$\begingroup$

In general, you have to read the datasheets in detail to know. Just that they "have FSK modulation" is not enough information to know if they are compatible. FSK is merely a modulation technique, not a complete and precise definition of a protocol. In addition to the RF modulation used, integrated transceivers typically include some digital encoding, FEC, and so on which again must be compatible on both ends.

If your objective is compatibility among integrated solutions, then it's probably easiest to either:

  • stick to one product line of one manufacturer, or
  • look for devices designed to comply with some standard protocol, like ZigBee, WiFi, Bluetooth, etc.
$\endgroup$
2
  • $\begingroup$ Thanks! I have read the datasheets (however I am not a professional communication engineer, so I cannot quite understand all the details ...). For example, both cc1120 and si4463 have GFSK modulation, they both support the same frequency range, they both can hop frequency in several tens of us. Some chip support FEC and digital encoding, but for compatibility's sake, these features can be disabled. I have searched the internet, however don't find someone do this kind of experiments ... Do you know someone who has experiences on this? $\endgroup$
    – jtuki
    Jun 12 '15 at 3:28
  • $\begingroup$ @jtuki the profession you are looking for is called an "RF engineer". I don't think you're going to get an easier answer to this question: the reason manufacturers produce lines of compatible RF components is because determining compatibility is a hard problem. If you don't understand the fundamentals, then you can hire a professional or learn the fundamentals yourself or use a product which is designed to address the concern of compatibility. $\endgroup$ Jun 12 '15 at 12:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.