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

Timestamp:

Nov 23, 2017, 8:26:42 PM (6 years ago)

Author:

tingjunchen

Comment:

—

Tutorials/k0SDR/Tutorial25

@@ -39 +39 @@
 
 === Run the Experiments ===
-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
+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.
 
 ==== In Terminal 1 (UHD) ====
- * Build the example:
+ * Build the example (this is already done in the loaded image):
 {{{
 cd ~/flexicon_orbit/fd_transceiver_simple/uhd/
@@ -50 +50 @@
 make
 }}}
- * Check the conection and serial number of the USRP N210 using command {{{uhd_find_devices}}}. The serial number should be {{{F331D4}}}.
+ * Configure the USRP Ethernet interface: {{{ifconfig eth2 192.168.10.1 netmask 255.255.255.0 up}}}
+ * Check the conection and serial number of the USRP N210: {{{uhd_find_devices}}}. The serial number should be {{{F331D4}}}.
  * Run the example with IQ rate {{{rate}}}, carrier frequency {{{freq}}}, TX gain {{{tx-gain}}}, and RX gain {{{rx-gain}}}:
 {{{
-./fd_transceiver_simple --tx-args="serial=F331D4" --rx-args="serial=F331D4" --rate 1e6 --freq 900e6 --tx-gain 10 --rx-gain 10
+cd ~/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
 }}}
- 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.
+ 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.
+ * An example temrinal output is below:
+{{{
+root@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
+linux; GNU C++ version 4.8.4; Boost_105400; UHD_003.010.001.001-0-unknown
+
+
+Creating the transmit usrp device with: serial=F331D4...
+-- Opening a USRP2/N-Series device...
+-- Current recv frame size: 1472 bytes
+-- Current send frame size: 1472 bytes
+
+.
+.
+.
+
+Press Ctrl + C to stop streaming...
+
+TX Stream time was: 0 full secs, 0.100064 frac secs
+
+RX Signal Power: -44.093768 dBm (N_FFt = 2048)
+RX Res Signal Power: -98.570747 dBm (N_fft = 1024)
+Amount of Digital SIC: 54.476979 dB
+
+RX Signal Power: -44.232740 dBm (N_FFt = 2048)
+RX Res Signal Power: -98.113147 dBm (N_fft = 1024)
+Amount of Digital SIC: 53.880407 dB
+
+RX Signal Power: -43.959299 dBm (N_FFt = 2048)
+RX Res Signal Power: -93.406544 dBm (N_fft = 1024)
+Amount of Digital SIC: 49.447245 dB
+
+RX Signal Power: -44.179891 dBm (N_FFt = 2048)
+RX Res Signal Power: -101.593147 dBm (N_fft = 1024)
+Amount of Digital SIC: 57.413256 dB
+}}}
 
 ==== In Terminal 2 (SUB-20) ====
- * Build the RF canceller configuration code:
+ * Build the RF canceller configuration code (this is already done in the loaded image):
 {{{
 cd ~/flexicon_orbit/fd_transceiver_simple/sub20/
@@ -66 +103 @@
  * Program and configure the RF canceller with the desired values:
 {{{
-./rf_canc_config ATT-CODE PS-CODE C1-CODE C2-CODE C3-CODE
+cd ~/flexicon_orbit/fd_transceiver_simple/sub20/
+./rf_canc_gen1_config PS-CODE ATT-CODE C1-CODE C2-CODE C3-CODE
 }}}
- 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.
+ 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.
+ * An example temrinal output is below:
+{{{
+root@node11-10:~/flexicon_orbit/fd_transceiver_simple/sub20# ./rf_canc_gen1_config 110 30 16 6 6
+Started...
+Sub20 device found... Serial Number is 48AB
+Device Opened!
+...Finished programming DAC with value 110!
+...Finished programming ATT with value 30!
+...Finished programming CAP1 with value 16!
+...Finished programming CAP2 with value 6!
+...Finished programming CAP3 with value 6!
+}}}
 
 ==== A Secondary Transmitter Using Node13-8 ====