Re: [Discuss-gnuradio] SWIG related problem with new filter function

[John Andrews]

Hi Tom,

Are you doing this in your own top-level block (dsss from the looks of it) or under a current GNU Radio directory like gnuradio-core where the gr_firdes currently is?

Yes, I am doing this in my own top-level directory named 'dsss' (abbreviation for direct sequence spread spectrum)

You haven't mentioned adding anything to the Makefile so that it is built properly. If you are working under gnuradio-core/src/lib/general, you'll also want to add your .h and .i files to general.i so that it get's compiled.

I added the names to Makefile.am like I added the remaining names of files. The Makefile.am has been adapted from howto-write-a-block. The C++ part gets compiled without any problem but when importing in python it throws an undefined_variable_dsss_firdes_Z*** type of error, which according to my previous experience occurs with wrong SWIG interface problem. I am pretty sure I am having a SWIG related issue here.

Also, just curious, what application are you interested in that requires a raised cosine filter? And couldn't you just create a root raised cosine filter and convolve the the taps against themselves to make the raised cosine taps?

I am developing a  BPSK based Direct sequence spread spectrum Tx/Rx and at the transmitter i wanted to use a raised cosine filter when interpolating from symbol to N samples before sending it to the USRP. I am not sure if this is the preferred method but I haven't found any documentation  related to DSSS that mentions pulse-shaping. 

Tom