Changes between Version 31 and Version 32 of Tutorials/k0SDR/Tutorial25


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Timestamp:
Nov 22, 2017, 7:38:04 PM (6 years ago)
Author:
tingjunchen
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  • Tutorials/k0SDR/Tutorial25

    v31 v32  
    5252./fd_transceiver_simple --tx-args="serial=F331D4" --rx-args="serial=F331D4" --rate 1e6 --freq 900e6 --tx-gain 10 --rx-gain 10
    5353}}}
    54  The default sine wave has an amplitude {{{ampl = 0.3}}} and wave frequency of 100kHz {{{wave-freq = 100e3}}}. This terminal window will show the power level at RX baseband, after RF cancellation (before digital) and after digital cancellation, respetively.
     54 The default sine wave has an amplitude {{{ampl=0.3}}} and wave frequency of 100kHz {{{wave-freq=100e3}}}. This terminal window will show the power level at RX baseband, after RF cancellation (before digital) and after digital cancellation, respetively.
    5555
    5656==== In Terminal 2 (SUB-20) ====
    … …  
    6363 * Program and configure the RF canceller with the desired values:
    6464{{{
    65 ./rf_canc_config ATT PS C1 C2 C3
     65./rf_canc_config ATT-CODE PS-CODE C1-CODE C2-CODE C3-CODE
    6666}}}
    67  In particular, the {{{ATT = 0, 1, 2, ..., 127}}} and {{{PS = 0, 1, 2, ..., 255}}} codes are for configuring the 7-bit attenuator and 8-bit phase shifter of the Gen-1 RF canceller. It is recommended to use {{{C1 = 16, C2 = 3, C3 = 9}}}. You can play with the values of {{{ATT}}} and {{{PS}}} until you see good cancellation profile (e.g., low residual self-interference power level) in Terminal 1.
     67 In particular, the {{{ATT-CODE=0,1,2,...,127}}} and {{{PS-CODE=0,1,2,...,255}}} codes are for configuring the 7-bit attenuator and 8-bit phase shifter of the Gen-1 RF canceller. It is recommended to use {{{C1-CODE=16, C2-CODE=3, C3-CODE=9}}}. You can play with the values of {{{ATT}}} and {{{PS}}} until you see good cancellation profile (e.g., low residual self-interference power level) in Terminal 1.
    6868
    6969==== A Secondary Transmitter Using Node13-8 ====
    … …  
    7777}}}
    7878 * Configure the USRP Ethernet interface: {{{ifconfig eth2 192.168.10.1 netmask 255.255.255.0 up}}}
    79  * Set up a secondary transmitter sending a sine wave at a different frequency (e.g., 200kHz) than that of the full-duplex node:
     79 * Set up a secondary transmitter sending a sine wave at a different frequency (e.g., 200 kHz) than that of the full-duplex node:
    8080{{{
    8181./tx_waveforms --args="serial=F331D4" --rate 1e6 --freq 900e6 gain 10 --wave-type SINE --wave-freq 200e3
    8282}}}
    83  Now
     83 Now by analyzing the RX baseband data at node11-10, you will observe the received tone at 200kHz while the self-interence tone at 100kHz is cancelled to the USRP noise floor, which is around -90dBm.
    8484