Can Xbee JUST transmit a pulse and another can detect it? Simple as this!

Hi there,

I would like to know whether or not Xbees are able to just send a pulse. Nothing more, no additional code spreading stuff and other "magic"! I need to transmit pulses as fast as possible I want to avoid additional processing. Furthermore I want to be able to code my own coded spreaded transmission.
So I couldn't find if Xbees can be transmit a signal if one pin of the arduino is high and stops doing this when it goes low.
I know, that Xbees are not designed to do such "simple" tasks, but perhaps they still can do it, if you force them somehow.

Thanks in advance,

Andreas

"As fast as possible" is pretty darned fast these days. What is your real requirement (numbers and units, please)?

XBees transmit digital information, period. There is no direct control over the radio, that's several layers down the stack. If you just want to do CW, you should look for a basic transmitter and receiver. There are simpler modules than XBees around, but I haven't used them, and I wonder whether they're simple enough for your requirement. I think most have digital inputs and do ASK or something similar.

Hi and thanks,

as far as I understand my situation right now, I need a signal sampling rate for keying and detection of >=40MHz. I don't need the transmission bandwidth, I just need to be able to detect it this fast and the signal edges should also be in one of those periods.
And a single pulse would would be required because it should be easy during the test phase. And of course the accuracy should be within a clock pulse. If this is jittering to much, it would ruin my measurements.

Perhaps LATER on, a code could be send instead, but then the signal processing should be also stable and within a clock pulse's accuracy.

What would you propose instead?

Best regards,

Andreas

This may be above my pay grade but there should be some folks here with some insights. I've forgotten most of what little I was taught about RF and I missed that you said spread spectrum. If a 40MHz sample rate is needed, that is several times the clock frequencies of the processors we usually discuss here, so I think I'd look to much faster systems.

Hi,

I came back to the Xbees and I found out that they can use API mode and Transparent Data Mode.
What does the last one do, because the first one is for sending packets and the latter one is described differently on some webpages. Do they really send out simple RF modulation, like AM or FM commands? I would like to get access to the modulation to send and receive my own packages, or implement code spreading techniques. But for this, I don't need all the handy "magic" xbee can do for me.
Is this simple mode possible?

Best regards,

Andreas

Transparent mode is basically a serial port replacement. Everything you send out the serial port goes out over the air, and everything received over the air is sent to the serial port. It sounds like the xbee is not what you want. You seem to require a RF transceiver that you can program yourself. Or you could build your own spark-gap transmitter. :slight_smile:

The XBee product manuals explain their operation in some detail. Have you read the product manual(s) for the model(s) of XBee that you are interested in? If not, you should go to the digi.com web site and get the manuals. I agree with the above post; from what I can tell, the features of the XBee modules are not a good match for your requirements.

I would like to get access to the modulation to send and receive my own packages, or implement code spreading techniques.

You can't do that with Xbee at all.
Sorry