Hi Marcus, I need help regarding the phase sync part that you mentioned in your previous post here.
"There's one thing that could use improvement in the echotimer code: If the set_?x_freq() were done after the time and clock sources had been set as a timed command (i.e. after calling set_command_time()), then the SBX daughterboards would always have the same phase relationship after tuning to the same frequency, which might be really handy in MIMO." This part I tried in python, however, I am not actually getting any phase sync between the receive files. I am not really sure whether defining freq after set_command_time() in python can really help. However, please let me know what modification should I make or what exactly I need to do. I am putting the python code here that I am using right now for 2 usrps. 2 TXs are in one x310 (on gpsdo) and 2 RXs are on the other one (external ref). and the connection is TX-wire-30_dB_attenuator-wire-RX, I am taking wired measurement. I am using 2.45 GHz freq. --------------------------- self.usrp_source0 = uhd.usrp_source( ",".join(("addr=172.xx.xx.73", "")), uhd.stream_args( cpu_format="fc32", channels=range(2), ), ) self.usrp_sink0 = uhd.usrp_sink( ",".join(("addr=172.xx.xx.75", "")), uhd.stream_args( cpu_format="fc32", channels=range(2), ), ) self.usrp_source0.set_clock_source("external", 0) self.usrp_source0.set_time_source("external", 0) self.usrp_source0.set_subdev_spec("A:0 B:0", 0) self.usrp_source0.set_time_unknown_pps(uhd.time_spec()) self.usrp_source0.set_samp_rate(samp_rate) self.usrp_source0.set_gain(26, 0) self.usrp_source0.set_antenna("RX2", 0) self.usrp_source0.set_gain(26, 1) self.usrp_source0.set_antenna("RX2", 1) self.usrp_sink0.set_clock_source("gpsdo", 0) self.usrp_sink0.set_time_source("gpsdo", 0) self.usrp_sink0.set_subdev_spec("A:0 B:0", 0) self.usrp_sink0.set_time_unknown_pps(uhd.time_spec()) self.usrp_sink0.set_samp_rate(samp_rate) self.usrp_sink0.set_gain(0, 0) self.usrp_sink0.set_antenna("TX/RX", 0) self.usrp_sink0.set_gain(0, 1) self.usrp_sink0.set_antenna("TX/RX", 1) time.sleep(1) print "receiver pps time:" cmd_time = self.usrp_source0.get_time_last_pps() print "transmitter pps time:" cmd_time0 = self.usrp_sink0.get_time_last_pps() real_seconds = uhd.time_spec_t.get_real_secs(cmd_time) real_seconds0 = uhd.time_spec_t.get_real_secs(cmd_time0) print real_seconds print real_seconds0 self.usrp_source0.set_time_next_pps(uhd.time_spec_t(0.0)) self.usrp_sink0.set_time_next_pps(uhd.time_spec_t(0.0)) now = self.usrp_source0.get_time_now() starttime = now + uhd.time_spec(1.5) self.usrp_source0.set_start_time(starttime) self.usrp_sink0.set_start_time(starttime) self.usrp_source0.set_center_freq(f, 0) self.usrp_source0.set_center_freq(f, 1) self.usrp_sink0.set_center_freq(f, 0) self.usrp_sink0.set_center_freq(f, 1) self.blocks_throttle_0_1 = blocks.throttle(gr.sizeof_gr_complex*1, samp_rate,True) self.blocks_throttle_0_0_0 = blocks.throttle(gr.sizeof_gr_complex*1, samp_rate,True) self.blocks_throttle_0_0 = blocks.throttle(gr.sizeof_gr_complex*1, samp_rate,True) self.blocks_throttle_0 = blocks.throttle(gr.sizeof_gr_complex*1, samp_rate,True) self.blocks_file_source_0_0 = blocks.file_source(gr.sizeof_gr_complex*1, "/home/sanjoy/Desktop/new/siso with new preamble 3/20150603_siso_echotimer/floatgen.bin", True) self.blocks_file_source_0 = blocks.file_source(gr.sizeof_gr_complex*1, "/home/sanjoy/Desktop/new/siso with new preamble 3/20150603_siso_echotimer/floatgen.bin", True) self.blocks_file_sink_0_0 = blocks.file_sink(gr.sizeof_gr_complex*1, "/home/sanjoy/Desktop/siso2.bin", False) self.blocks_file_sink_0_0.set_unbuffered(False) self.blocks_file_sink_0 = blocks.file_sink(gr.sizeof_gr_complex*1, "/home/sanjoy/Desktop/siso1.bin", False) self.blocks_file_sink_0.set_unbuffered(False) ----------------------------- My system config is usrp X310, daughterboard SBX-120, uhd 3.9. best regards Sanjoy -- Posted via http://www.ruby-forum.com/. _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio