On 04/10/2013 12:27 AM, Rahman, Muhammad Mahboob Ur wrote: > Hi Josh, > >> So it would be possible to mute the ADC samples when the device is >> transmitting. However, that might only be desirable in a couple of >> use cases, and there are probably a dozen ways to solve this from >> all the way down at the physical layer up the the MAC layer: > >> * mute the RX ADC when transmitting (probably an FPGA mod) > > > We are interested to operate our USRP N200 radios in TDM. In other > words, we want each of our radio to transmit and receive at the same > frequency. Since we expect very high self-interference in this case, > we would be interested to play a little bit with the ADC mute option. > Could you provide us some pointers on where to modify the FPGA code > to do this? Also, how much realistic/feasible it sounds if we want to
https://github.com/EttusResearch/uhd/blob/master/fpga/usrp2/top/N2x0/u2plus_core.v See the section at line 614? Use the run_tx signal to conditionally zero out the values going to .adc_a and .adc_b > control ADC (on/off) switching from within the GRC flow graph (at the > very least, we will expect some latency associated with this > operation). > If you are running continuous receive, by knowing the transmit time of a packet - or based on some concept of valid transmit window, you can choose what rx samples to ignore based on the rx sample's timestamps. -- that would be the most exact way to do it. -josh > > Thanks in anticipation, Mahboob > _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
