Changes between Version 38 and Version 39 of Tutorials/g0WmLTE/Tutorial5


Ignore:
Timestamp:
Jul 12, 2016, 12:20:28 PM (8 years ago)
Author:
seskar
Comment:

—

Legend:

Unmodified
Added
Removed
Modified

  • Tutorials/g0WmLTE/Tutorial5

    v38 v39  
    1414 1. It will take roughly 60 seconds to come up.
    15151. {{{ ssh root@node7-1.grid.orbit-lab.org }}}
     16
    1617=== Commands on the node ===
    17 By Default Orbit nodes do not configure any wireless devices. The following 2 are the drivers for the Sierra wireless Netgear LTE dongle [[BR]]
    18 1. {{{ modprobe GobiSerial }}}
    19 1. {{{ modprobe GobiNet }}}
    20 1. {{{ minicom -D /dev/ttyUSB1 }}}
    21 1. {{{ AT!ippassthrough? }}}
    22  1. It should return 1
    23  1. If it does not, run the following commands:
    24   1. {{{ AT!ippassthrough=1 }}}
    25   1. {{{ AT!entercnd="A710" }}}
    26   1. {{{ AT!dxcfg=profile,Autoconnect,Never }}}
    27   1. {{{ AT!reset }}}
    28 1. {{{ AT!entercnd="A710" }}}
    29  1. You should see {{{ OK }}}
    30 1. {{{ AT!dxcfg=wwan,connect,11 }}}
    31  1. You should see {{{ OK }}} then {{{ $QCRMCALL: 1, V4 }}}
    32 1. {{{ at!gstatus? }}}
    33  1. Will return a status like:
     18
     19==== Loading the driver ====
     20
     21By Default Orbit nodes do not configure any wireless devices so the first thing, when manually configuring the device is to load the drivers; the following 2 lines will load the Sierra wireless Netgear LTE dongle:[[BR]]
     22{{{
     23modprobe GobiSerial
     24modprobe GobiNet
     25}}}
     26
     27==== Connecting to the device ====
     28Control of the device is done over the serial port that is created by the driver (in this case '''/dev/ttyUSB1''') through a sequence of AT commands and you can use your favorite serial port communication program to talk to it; in this tutorial we will use '''Minicom''. To start to program execute:
     29
     30{{{ minicom -D /dev/ttyUSB1 }}}
     31
     32==== Managing the LTE connection ====
     33
     34Once in minicom, one can issue series of commands to the LTE modem typically consisting of:
     35
     36a.) Configure modem for pass-through mode:
     37
     38{{{ AT!ippassthrough? }}}
     39
     40It should return '''1''' . If it does not, run the following commands:
     41    1. {{{ AT!ippassthrough=1 }}}
     42    1. {{{ AT!entercnd="A710" }}}
     43    1. {{{ AT!dxcfg=profile,Autoconnect,Never }}}
     44    1. {{{ AT!reset }}}
     45which will reset the modem.
     46
     47b.)
     48
     49{{{ AT!entercnd="A710" }}}
     50
     51You should see {{{ OK }}}
     52
     53c.) Connect to the basestation:
     54
     55{{{ AT!dxcfg=wwan,connect,11 }}}
     56
     57You should see {{{ OK }}} shortly followed by {{{ $QCRMCALL: 1, V4 }}}
     58
     59d.) Check the status of the connection:
     60
     61{{{ at!gstatus? }}}
     62
     63Will return a status like:
    3464{{{
    3565at!gstatus?                                                                                                         
    … …  
    4979SINR (dB):      1.6
    5080}}}
    51 1. Exit Minicom by **PRESSING** {{{ Ctrl+A followed by x}}}, then {{{enter}}} to select ok.
    52 1. {{{ dhcpcd eth2 }}} followed by {{{enter}}} to get a new line.
    53  1. You should get an address in the 192.168.3.0/24 subnet.
    54 1. {{{ ping 192.168.3.1 }}}
    55  1. You have successfully communicated with the basestation.
    56  1. You can cancel the ping with {{{Ctrl+C}}}
    57 1. Attempt running iperf between your nodes.
    58  1. This will report your bandwidth to the basestation.
     81
     82The LTE link is established. Exit Minicom by **PRESSING** {{{ Ctrl+A followed by x}}}, then {{{enter}}} to select '''OK''' option.
     83
     84==== Testing the connection ====
     85
     86Once the modem is connected, IP address has to be assigned to the newly created Ethernet device (in this case '''eth2'''):
     87
     88{{{ dhcpcd eth2 }}}
     89
     90The node should get an address in the 192.168.3.0/24 subnet (any existing dhcpd instance on eth2 has to be killed). Use ICMP to test connectivity with the default gateway:
     91{{{ ping 192.168.3.1 }}}
     92resulting in:
     93{{{
     94root@node1-7:~# ping 192.168.3.1
     95PING 192.168.3.1 (192.168.3.1) 56(84) bytes of data.
     9664 bytes from 192.168.3.1: icmp_seq=1 ttl=64 time=44.9 ms
     9764 bytes from 192.168.3.1: icmp_seq=2 ttl=64 time=42.8 ms
     98}}}
     99The ping can be canceled with {{{Ctrl+C}}}. More elaborate link performance test can be done by using '''iperf''' between multiple nodes that are connected to the basestation.
     100
     101==== Reconnecting the client ====
     102
     103Use minicom (or any other serial port program) to issue a set of AT commands to reset the connection. Commands are:
     104
     105{{{
     106AT!reset
     107}}}
     108
     109(NOTE: after the AT!reset command the minicom will display the popup window that the connection was lost- one has to wait for the pop-up to go away before proceeding)
     110
     111{{{
     112AT!entercnd="A710"
     113AT!dxcfg=wwan,connect,11
     114}}}
     115
     116The output should look like:
     117{{{
     118root@node1-7:~# minicom -D /dev/ttyUSB1
     119
     120Welcome to minicom 2.7
     121
     122OPTIONS: I18n
     123Compiled on Jan  1 2014, 17:13:19.
     124Port /dev/ttyUSB1, 06:02:02
     125
     126Press CTRL-A Z for help on special keys                 
     127                                                       
     128AT                                                       
     129OK                                                     
     130AT!reset                                               
     131OK
     132AT!entercnd="A710"
     133OK
     134AT!dxcfg=wwan,connect,11
     135OK
     136
     137$QCRMCALL: 1, V4
     138at!gstatus?
     139!GSTATUS:
     140Current Time:  58               Temperature: 28     
     141Bootup Time:   6                Mode:        ONLINE         
     142System mode:   LTE              PS state:    Attached                           
     143LTE band:      B25              LTE bw:      10 MHz                             
     144LTE Rx chan:   8365             LTE Tx chan: 26365                             
     145EMM state:     Registered       Normal Service                                 
     146RRC state:     RRC Connected                                                   
     147IMS reg state: No Srv                                                           
     148                                                                               
     149RSSI (dBm):    -69              Tx Power:    -33                               
     150RSRP (dBm):    -90              TAC:         0001 (1)                           
     151RSRQ (dB):     -5               Cell ID:     01A2D001 (27447297)               
     152SINR (dB):     21.2                                                             
     153                                                                               
     154                                                                               
     155OK                                                                             
     156}}}
     157
     158Once connection is reset, dhcp lease needs to be renewed; if there is already dhcpd session it needs to be terminated:
     159
     160{{{
     161root@node1-7:~# dhcpcd eth2
     162err, eth2: dhcpcd already running on pid 2071 (/var/run/dhcpcd-eth2.pid)
     163root@node1-7:~# kill 2071
     164root@node1-7:~# dhcpcd eth2
     165root@node1-7:~# dhcpcd.sh: interface eth2 has been configured with new IP=192.168.3.2
     166
     167root@node1-7:~#
     168}}}
     169
     170
     171=== Managing the basestation ===
     172
     173Uses rest interface to manage the BS. To set the LTE connection bandwidth to 5 MHz issue the following commands on the console (not node):
     174{{{
     175wget http://bsc03out.orbit-lab.org:5054/bscontrol/bs/1/default_cell_parameters?n_rb_dl=25     
     176wget http://bsc03out.orbit-lab.org:5054/bscontrol/bs/1/restart
     177}}}
     178
     179Setting '''n_rb_dl''' to 50 sets it to 10 MHz while setting it to 100 sets the bandwidth to 20 MHz.
     180After basestatin restart, most of the clients need to be also reconnected.
     181