IBM 28GHz PAAM Basics

Description

In this tutorial, we demonstrate the basic use of the IBM 28GHz phased array antenna modules (PAAMs) with USRP N310 software-defined radios (SDRs) in the ​COSMOS Sandbox2 (sb2).

Author: Tingjun Chen, Duke University / Columbia University (tingjun.chen [at] duke [dot] edu)

Last updated: Apr. 11, 2021

Prerequisites

In order to access sb2, create a reservation in sb2 and have it approved by the reservation service. Access to the resources is granted after the reservation is confirmed. Please follow the process shown on the COSMOS getting ​started page to get started.

Resources Required

• 2 USRP N310 SDRs (sdr1-s1-lg1 and sdr1-md1)
• 2 IBM 28GHz PAAMs (rfdev2-1 and rfdev2-2)
• 1 Server (srv1-lg1)

Tutorial Setup

Follow the steps below to gain access to the sb2 console and set up nodes with appropriate images.

1. If you don't have one already, sign up for a ​COSMOS account
2. Create a resource reservation on COSMOS sb2
3. Login into sb2 console (console.sb2.cosmos-lab.org) with two SSH sessions.
4. Make sure all the nodes and devices used in the experiment are turned off:

   omf tell -a offh -t sdr1-s1-lg1,sdr1-md1,rfdev2-1,rfdev2-2,srv1-lg1
   

5. Use the baseline-28ghz-paam.ndz node image with Ubuntu 18.04, UHD 3.15, gnuradio 3.8, and the IBM 28GHz PAAM API. Load baseline-28ghz-paam.ndz on the server.

   omf load -i baseline-28ghz-paam.ndz -t srv1-lg1
   

6. Turn all the required resources on and check the status of all resources

   omf tell -a on -t sdr1-s1-lg1,sdr1-md1,rfdev2-1,rfdev2-2,srv1-lg1
   

   omf stat -t system:topo:allres
   

7. ssh to the the same server from two terminals. In the first terminal, use option -Y for using GUI with gnuradio. In the second terminal, option -Y is not needed as it will be used to control the two IBM 28GHz PAAMs via command lines.

   [Terminal 1] ssh -Y root@srv1-lg1,
   [Terminal 2] ssh root@srv1-lg1,
   

Experiment Execution

Find and prepare USRPs and the IBM 28GHz PAAM API

• The IP addresses for Ethernet Port 1 (10G) on sdr1-s1-lg1 and sdr1-md1 were hard-coded to 10.117.2.1 and 10.117.3.1, respectively. To access them from srv1-lg1, configure the network interface eno1 as follows:

  root@srv1-lg1:~# ifconfig eno1 10.117.1.1 netmask 255.255.0.0 mtu 9000 up
  root@srv1-lg1:~# sudo sysctl -w net.core.wmem_max=62500000
  net.core.wmem_max = 62500000
  root@srv1-lg1:~# sudo sysctl -w net.core.rmem_max=62500000
  net.core.rmem_max = 62500000
  root@srv1-lg1:~# ifconfig 
  eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 9000
          inet 10.117.1.1  netmask 255.255.0.0  broadcast 10.117.255.255
          inet6 fe80::1e34:daff:fe42:d4c  prefixlen 64  scopeid 0x20<link>
          ether 1c:34:da:42:0d:4c  txqueuelen 1000  (Ethernet)
          RX packets 15305870  bytes 21326136765 (21.3 GB)
          RX errors 0  dropped 46450  overruns 0  frame 0
          TX packets 16288829  bytes 21257264625 (21.2 GB)
          TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
  
  

• Run und_find_devicec to make sure that both USRP N310s can be reached:

  root@srv1-lg1:~/beta_20200928/examples# uhd_find_devices 
  [INFO] [UHD] linux; GNU C++ version 7.5.0; Boost_106501; UHD_3.15.0.HEAD-0-gaea0e2de
  --------------------------------------------------
  -- UHD Device 0
  --------------------------------------------------
  Device Address:
      serial: 315A35A
      addr: 10.117.2.1
      claimed: True
      mgmt_addr: 10.116.2.1
      mgmt_addr: 10.117.2.1
      mgmt_addr: 10.118.2.1
      product: n310
      type: n3xx
  
  --------------------------------------------------
  -- UHD Device 2
  --------------------------------------------------
  Device Address:
      serial: 3176DF7
      addr: 10.117.3.1
      claimed: True
      mgmt_addr: 10.116.3.1
      mgmt_addr: 10.117.3.1
      mgmt_addr: 10.118.3.1
      product: n310
      type: n3xx
  

• Download and build the RENEW Sounder software on the develop branch at ​here and follow the ​instructions to build it. Note that the master branch does not have UHD support.

• Include in files/usrp-bs-serials.txt the IP address 10.118.2.2, i.e., use sdr2-s1-lg1 as the base station (BS). In files/usrp-bs-only.json, set "channel" : "AB", to enable dual-channel on sdr2-s1-lg1.

• Similarly, in files/usrp-client-only.json, set "sdr_id" : [ "10.118.3.2" ] (i.e., use sdr2-md1 as the user) and "channel" : "AB", to enable dual-channel on sdr2-md1.