Changes between Version 8 and Version 9 of Tutorials/Wireless/Outdoor Spectrum Usage

Timestamp:

Jun 16, 2020, 5:44:55 PM (5 years ago)

Author:

nilanjan

Comment:

—

Tutorials/Wireless/Outdoor Spectrum Usage

@@ -294 +294 @@
 
 
-In the [next part of this tutorial] we'll edit the the receiving sdr application to store measured data to a remote network Influx database.
-
+In the [next part] we'll briefly show how to access measure data on Influx DB.
+
+=== View recorded data parameters in Influx DB using Grafana ===
+
+On the receiving side sdrapp, enable the OML recording capability by recompiling the application with the _USE_OML_ flag. (If the application is still running, be sure to stop the application by doing Ctrl-C and exit out of the node back to the console again.)
+
+Edit the Makefile by adding ''-D_USE_OML_'' at the end of CPPFLAGS.
+
+{{{#!shell
+CPPFLAGS ?= $(INC_FLAGS) -MMD -MP -Ofast --fast-math -finline-functions -std=c++11 -D_USE_OML_
+}}}
+
+Now rebuild the application from the console. This enables the recording of  paramters displayed on the console into Influx DB - namely: seq_num, pkt_len, corr_strength. These values will be written to InFlux DB under a database name ''collectd'' and a sender id ''rx_data_link_0''. 
+
+{{{#!shell-session
+user@console:~$ make remote-make
+}}}
+
+
+We'll run the application for a longer duration so a large set of values are recorded for viewing. Edit the ''run_data_script.sh'' script so the receive and transmit handlers are run for 2000 seconds.
+
+{{{#!shell
+## BEGIN data transfer
+##  Invoke receive handler
+##                       rxsig_data <runtime_in_milliseconds> <correlation threshold>
+python rc.py $RXNODE 5180 "rxsig_data 2000000 10000"
+
+
+##  Invoke transmit handler
+##                       txsig_data <runtime_in_milliseconds> <delay_between_burst_in_msec>
+python rc.py $TXNODE 5180 "txsig_data 2000000 1000"
+
+echo "DONE!"
+}}}
+
+Rerun both applications also make sure the RF front end is turned on. The receiver will record the paramters for each detected packet.
+{{{#!shell
+user@console:~$ curl "am1.cosmos-lab.org:5054/rf_control/set_tx_path?node=sdr2-s3-lg1.bed.cosmos-lab.org&rf_port=0&power_amp=on&f_lower=2500&f_upper=2680"
+}}}
+
+The recorded values can be queried from the console with a call to the [https://docs.influxdata.com/influxdb/v1.7/guides/querying_data/ InfluxDB API].
+
+{{{#!shell
+curl -XPOST 'http://idb2:8086/query?db=collectd&pretty=true' --data-binary 'q=select * from _mp__collectd'
+:
+    "results": [
+        {
+            "statement_id": 0,
+            "series": [
+                {
+                    "name": "_mp__collectd",
+                    "columns": [
+                        "time",
+                        "corr_threshold",
+                        "pkt_len",
+                        "sender_id",
+                        "seq_no",
+                        "seq_num",
+                        "time_stamp",
+                        "time_stamp_server"
+                    ],
+                    "values": [
+                        [
+                            "2020-06-16T15:44:04.310022857Z",
+                            32221.601562,
+                            7,
+                            "rx_data_link_0",
+                            "1",
+                            1,
+                            "2.266386",
+                            "2.309666"
+                        ],
+
+:
+:
+:
+                        [
+                            "2020-06-16T16:17:20.274931375Z",
+                            35238.019531,
+                            2,
+                            "rx_data_link_0",
+                            "2049",
+                            205,
+                            "1998.270517",
+                            "1998.274432"
+                        ],
+                        [
+                            "2020-06-16T16:17:21.276384485Z",
+                            35233.40625,
+                            63,
+                            "rx_data_link_0",
+                            "2050",
+                            206,
+                            "1999.272047",
+                            "1999.276026"
+                        ],
+                        [
+                            "2020-06-16T16:17:22.276512538Z",
+                            35226.476562,
+                            34,
+                            "rx_data_link_0",
+                            "2051",
+                            207,
+                            "2000.272036",
+                            "2000.276081"
+                        ]
+
+:
+}}}
+
+
+The recorded values can also be view on a web browser using Grafana as the front end. In order to have the web browser access the Grafana server, a tunnel was created from localhost port 3000 to idb2:3000.
+
+Following is a trace of the correlation threshold. 
+[[Image(wiki:WikiFormatting:influx_corr_thresh)]]
+
+At the end of you session remember to turn off the RF front end with the following command.
+
+{{{#!shell-session
+user@console:~$ curl "am1.cosmos-lab.org:5054/rf_control/set_tx_path?node=sdr2-s3-lg1.bed.cosmos-lab.org&rf_port=0&power_amp=off"
+<response status="OK">
+  <message>OK</message>
+</response>
+}}}