MSK de-/modulation

GNU Radio
1

Hello,

Did anyone write blocks for MSK de-/modulation? I couldn’t find
anything in the gnuradio-core directory and I wanted to ask before I
start implementing it in order to avoid duplicated work.

Thomas

2

Thomas S. wrote:

Hello,

Did anyone write blocks for MSK de-/modulation? I couldn’t find
anything in the gnuradio-core directory and I wanted to ask before I
start implementing it in order to avoid duplicated work.

The code for GMSK will work with some minor tweaks for plain MSK.

Matt

3

Hi Matt,

Can you give me some pointers on what I would have to tweak in the
GMSK code? I read up on MSK but most demodulators I found use
integration of the I and Q phases and then proper slicing. I can see
how that works if I have synchronization, but I don’t know how to
achieve that.

Here some more details on what I try to do: I try to decode a message
sent out by a chipcon CC2420 in the 2.4GHz ISM band. The over all
symbol rate is 2Mchip/s, thus I sample at 4MHz.

Thomas