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How to 3 RF Transceivers (Wixel) Pairing


#1

Hi,
I am newbie on wireless communication. I have a project that is related to the RF Modules. I want to set up a wireless network between 3 RF Modules (why RF Modules - because they are cheap…I guess???). I picked 2.4 GHz RF Modules because of there will be more than one set (set includes 3 RF Modules). I don’t want my sets interact each other (interference their signal each other signal …right?).

First,
I don’t how this 2.4 GHz RF Module works. How they pair each other? Unlike 27 MHz receiver (ex. Like RC Cars… if you have RC cars working on the same frequency, you can control two cars with one controller). At the 2.4 GHz, why is this interference not occur? (Because of FHSS or DSSS… ??? or at the software side— add some bytes to signal for identification???). How these 2.4 GHz receiver and transmitter know each other? (Is this word correct – PAIRING ? or SYNC? ). I am really sorry. I know this is really basic thing, but I didn’t find any answer. Try to understand for next steps…

Second,
My project is not sending signal between two RF Modules. I try to use 3 RF Modules— one for receive other two for transmit the my control signal. Basically, I have an idea that is One Robot that performs two different tasks (first task basic things moving right/left/forward/backward-- these are control with one controller and second task control arms and head etc…-- controls with second controller). At the medium, there will be may be 10 robots, so I don’t need any interference (don’t control other’s robot vice verse…) I have attached a diagram. I searched that I found something like DATA PIPE… I believe that will work for this configuration right??.
I bought 3 Wixel RF modules. Does Wixel support this? ( Does Wixel have data pipe feature?— OR do I need data pipe for set up this network? )

Help me please. I will appreciate…

Attached block diagram

I tried to explain…
Thank you so Much…


#2

Hello. The answers to your questions will depend on which 2.4 GHz RF module you are asking about so I will assume you are asking about the Wixel. The answers can also depend on which Wixel App you are running, because the Wixel’s radio itself is pretty versatile and can be used in different ways.

When people say “2.4 GHz” they are actually referring to an entire band of frequencies from 2.4 to 2.5 GHz. Within that range, devices can choose which frequencies they are actually broadcasting and listening on. Wixels are “paired” just be setting them to use the same frequency (a.k.a. channel). When two Wixels are on the same channel, then a packet transmitted by one can be received by the other. They also need to have compatible radio configuration settings, but you will NOT need to worry about that because we have already figured it out. It would also be possible to add an ID byte to the packets as you suggested, but we have not done that. The Wixel apps we provide do not implement FHSS or DSSS.

I do not know what “DATA PIPE” refers to. Please provide a link to that if you want to know about it. We provide various radio libraries for the Wixel that you could use to set up a data pipe.

I think you might be able to complete your project without actually delving into Wixel programming. I recommend that you try using the I/O Repeater app, which you can download from the Wixel User’s Guide. Each group of three would be on a different radio channel, ensuring that they don’t interfere with eachother.

–David