Any ideas or comments will be helpful for me and I am anxiously waiting!!!.
Kaleem Ahmad kaleem ahmad wrote: > > Hello everyone, > > I am trying to implement a simple FSK system to measure bit error rate > (BER), and packet loss rate (PLR) using: > > 1-Linux > 2-USRP motherboard > 3-RFX2400 daughter card > > I want to implement an echo back system where one Transceiver (say Master) > will transmit a small frame (let say 48 byte, and important thing is that > I neccessarily need small payload) to other transceiver (say Slave). The > Salve returns the frame immediatelly without any processing to Master and > Master measures BER and PLR. > > The problem which I am facing is that I am unable to transmitt such small > packets. I have noticed that if I have a large file with let say few > Kbytes contents then it is transmitted (partially, the end of file is > always missing...I guess it is stuck somewhere in buffer????) but if I > have such small packets as I metioned earlier then most of the time the > packets are lost. If the packet is received then it is totally corrupt > (say almost 100% BER) unlike large files which are received in very good > quality (But important and notable point is that even the large files are > 100% courrupt at the end). This makes me wonder why last few hundered > bytes are always courrupt??? (for small file the whole file lies in that > category of last few hundered bytes) > > I have tried a lot but unable to solve the problem! Now can any one help > me to understand what can be the problem? Is it somewhere in the buffers? > Is it some sort of synchronization problem??? and which buffers (of > USRP/RFX2400/GNURadio) are involved in such flowgraph. The flow graph with > actual names of blocks used by me is given below (I have attached complete > code if some one want to have a look): > > Transmit path flowgraph: > > gr.file_source -> gr.simple_framer -> gr.bytes_to_syms -> > gr.interp_fir_filter_fff -> gr.frequency_modulator_fc -> > gr.multiply_const_cc -> usrp.source_c > > Receive path flowgraph: > > usrp.source_c -> gr.fir_filter_ccf -> gr.quadrature_demod_cf -> > simple_correlator -> gr.file_sink > > Best Regards > > Kaleem Ahmad > > http://www.nabble.com/file/p19415046/fsk_rx.py fsk_rx.py > http://www.nabble.com/file/p19415046/fsk_tx.py fsk_tx.py > -- View this message in context: http://www.nabble.com/RFX2400%2BUSRP-buffers-tp19415046p19430641.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
