Changes between Version 35 and Version 36 of Tutorials/k0SDR/Tutorial25


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Timestamp:
Nov 23, 2017, 8:26:42 PM (7 years ago)
Author:
tingjunchen
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  • Tutorials/k0SDR/Tutorial25

    v35 v36  
    3939
    4040=== Run the Experiments ===
    41 You will need to login into the full-duplex node (by {{{ssh root@node11-10}}}) in two separate terminal windows lo for running the experiment: one for the main full-duplex transceiver UHD program and one for controlling the RF canceller
     41You will need to login into the full-duplex node (by {{{ssh root@node11-10}}}) in two separate terminal windows lo for running the experiment: one for the main full-duplex transceiver UHD program and one for controlling the RF canceller.
    4242
    4343==== In Terminal 1 (UHD) ====
    44  * Build the example:
     44 * Build the example (this is already done in the loaded image):
    4545{{{
    4646cd ~/flexicon_orbit/fd_transceiver_simple/uhd/
     
    5050make
    5151}}}
    52  * Check the conection and serial number of the USRP N210 using command {{{uhd_find_devices}}}. The serial number should be {{{F331D4}}}.
     52 * Configure the USRP Ethernet interface: {{{ifconfig eth2 192.168.10.1 netmask 255.255.255.0 up}}}
     53 * Check the conection and serial number of the USRP N210: {{{uhd_find_devices}}}. The serial number should be {{{F331D4}}}.
    5354 * Run the example with IQ rate {{{rate}}}, carrier frequency {{{freq}}}, TX gain {{{tx-gain}}}, and RX gain {{{rx-gain}}}:
    5455{{{
    55 ./fd_transceiver_simple --tx-args="serial=F331D4" --rx-args="serial=F331D4" --rate 1e6 --freq 900e6 --tx-gain 10 --rx-gain 10
     56cd ~/flexicon_orbit/fd_transceiver_simple/uhd/build/
     57./fd_transceiver_simple --tx-args="serial=F331D4" --rx-args="serial=F331D4" --rate 1e6 --freq 900e6 --tx-gain 0 --rx-gain 10
    5658}}}
    57  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.
     59 The default sine wave has an amplitude {{{ampl=0.3}}} and wave frequency of 100kHz {{{wave-freq=100e3}}}, which corresponds to a 0dBm TX power level. This terminal window will show the power level at RX baseband, after RF cancellation (before digital) and after digital cancellation, respetively. The UHD program is calibrated with {{{--rx-gain=10}}}, other RX gain values may results in inaccurate power level computation.
     60 * An example temrinal output is below:
     61{{{
     62root@node11-10:~/flexicon_orbit/fd_transceiver_simple/uhd/build# ./fd_transceiver_simple --tx-args="serial=F331D4" --rx-args="serial=F331D4" --rate 1e6 --freq 900e6 --tx-gain 0 --rx-gain 10
     63linux; GNU C++ version 4.8.4; Boost_105400; UHD_003.010.001.001-0-unknown
     64
     65
     66Creating the transmit usrp device with: serial=F331D4...
     67-- Opening a USRP2/N-Series device...
     68-- Current recv frame size: 1472 bytes
     69-- Current send frame size: 1472 bytes
     70
     71.
     72.
     73.
     74
     75Press Ctrl + C to stop streaming...
     76
     77TX Stream time was: 0 full secs, 0.100064 frac secs
     78
     79RX Signal Power: -44.093768 dBm (N_FFt = 2048)
     80RX Res Signal Power: -98.570747 dBm (N_fft = 1024)
     81Amount of Digital SIC: 54.476979 dB
     82
     83RX Signal Power: -44.232740 dBm (N_FFt = 2048)
     84RX Res Signal Power: -98.113147 dBm (N_fft = 1024)
     85Amount of Digital SIC: 53.880407 dB
     86
     87RX Signal Power: -43.959299 dBm (N_FFt = 2048)
     88RX Res Signal Power: -93.406544 dBm (N_fft = 1024)
     89Amount of Digital SIC: 49.447245 dB
     90
     91RX Signal Power: -44.179891 dBm (N_FFt = 2048)
     92RX Res Signal Power: -101.593147 dBm (N_fft = 1024)
     93Amount of Digital SIC: 57.413256 dB
     94}}}
    5895
    5996==== In Terminal 2 (SUB-20) ====
    60  * Build the RF canceller configuration code:
     97 * Build the RF canceller configuration code (this is already done in the loaded image):
    6198{{{
    6299cd ~/flexicon_orbit/fd_transceiver_simple/sub20/
     
    66103 * Program and configure the RF canceller with the desired values:
    67104{{{
    68 ./rf_canc_config ATT-CODE PS-CODE C1-CODE C2-CODE C3-CODE
     105cd ~/flexicon_orbit/fd_transceiver_simple/sub20/
     106./rf_canc_gen1_config PS-CODE ATT-CODE C1-CODE C2-CODE C3-CODE
    69107}}}
    70  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.
     108 In particular, the {{{PS-CODE=0,1,2,...,255}}} and {{{ATT-CODE=0,1,2,...,127}}} codes are for configuring the 8-bit phase shifter and the 7-bit attenuator of the Gen-1 RF canceller, respectively. It is recommended to use {{{C1-CODE=16, C2-CODE=6, C3-CODE=6}}}, which provides 20dB isolation from the antenna-circulator interface. 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.
     109 * An example temrinal output is below:
     110{{{
     111root@node11-10:~/flexicon_orbit/fd_transceiver_simple/sub20# ./rf_canc_gen1_config 110 30 16 6 6
     112Started...
     113Sub20 device found... Serial Number is 48AB
     114Device Opened!
     115...Finished programming DAC with value 110!
     116...Finished programming ATT with value 30!
     117...Finished programming CAP1 with value 16!
     118...Finished programming CAP2 with value 6!
     119...Finished programming CAP3 with value 6!
     120}}}
    71121
    72122==== A Secondary Transmitter Using Node13-8 ====