Hello Marcus,
Thank you again for your help last time. I'm using both LFTX daughterboard and LFRX daughterboard 0-30 Mhz on top of the N210. Also I reduced the sampling rate to a rate that the USRP can support. I removed the throttle and the BER block reading was 0.112. To me 11% lose considered high at distance of 10cm. I don't see any overrun sign on the console but "D" and it fixed after assigning 200K sample rate. i know the input for the modulation is packet and output of demod is bytes to get bits I have to unpack them but and this what I did but One more question is the input to the BER block equal? am I missing to adjust important parameter?
Thank you.