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Centralized Arbitrary Noise Injection Subsystem

This subsystem consists of a central arbitrary waveform generator (Agilent ESG) connected to four distribution antennas through a RF switch. Using this subsystem, users can inject individually controllable noise into the ORBIT grid using the antennas.

Webservice commands

<serviceGroup name="interference">
  <info>Interference injection control service</info>
  <service name="awgn">
     <info>Configures interference injection singal type to AWGN</info>
     <args>
        <arg name="bandwidth" value="noise BW in MHz"/></args>
  </service>
  
  <service name="initialize">
     <info> Resets interference injection subsystem to default state </info>
  </service>

  <service name="set">
     <info>Set global interference injection parameters</info>
     <args><arg name="power" value="noise power in dBm"/>
           <arg name="channel" value="802.11 channel number"/>
           <arg name="frequency" value="interference center frequency"/>
           <arg name="antenna-atten-1" value="attenuation in db"/>
           <arg name="antenna-atten-2" value="attenuation in db"/>
           <arg name="antenna-atten-3" value="attenuation in db"/>
           <arg name="antenna-atten-4" value="attenuation in db"/>
     </args>
  </service>
  
  <service name="start">
       <info>Turn on interference injection</info>
  </service>
  
  <service name="status">
	<info>Show current status of the interference injection subsystem</info>
  </service>
  
  <service name="stop">
        <info>Turn off interference injection</info>
  </service>
  
  
</serviceGroup>

Example

To set AWGN on channel 36 at -30 dBm on antenna1 use the following commands (either through a browser or wget)

• Step 1: Select AWGN bandwidth (channel bw for 802.11a/b/g is 20 Mhz)

        wget http://instrument1.orbit-lab.org/awgn?bandwidth=20
  

• Step 2: Set power level to -30 dBm

        wget http://instrument1.orbit-lab.org/set?power=-30
  

• Step 3: Set channel number to 36

        wget http://instrument1.orbit-lab.org/set?channel=36
  

• Step 4: Start RF injection

        wget http://instrument1.orbit-lab.org/start
  

At the end of the experiment,

• Step 5: Stop RF injection

        wget http://instrument1.orbit-lab.org/stop