CRAWDAD init/robotarm

Time- and frequency-variant 2.4 GHz ISM band channel gain. 

The time- and frequency-variant channel gain is measured in the presence of an industrial cyclic moving robot arm obstacle for four coexisting wireless nodes for the whole license-free 2.4-GHz-ISM band with a time- and frequency-resolution of 110 microseconds and 1 MHz, respectively. Results for two links are given.

date/time of measurement start: 2015-05-11

date/time of measurement end: 2015-05-11

collection environment: We measured the channel gain of two wireless links with a moving robot arm between the antennas. The robot arm was surrounded by a square ground acrylic glass box, which is placed in an indoor hall. We placed 4 antennas on the acrylic glass box and measured the varying channel gain for about 6.5 seconds.

network configuration: The robot arm is manufactured by KUKA Roboter GmbH, product model KR5 sixx R650. It was parameterized to a periodic movement cycle with repetition times of 1293.6 ms at 100% speed for measurement M1 and 2105.2 ms at 50% speed for measurement M2 to achieve a time fading channel behaviour.

data collection methodology: The vector signal generator (VSG) Rohde and Schwarz SMBV100A was used as a modulated signal source with center frequency of 2.44 GHz. The VSG was transmitting periodic short-time bursts via the wireless channel, seeking approximation of a wide-band Dirac pulse train with a bandwidth above 80 MHz. The real-time spectrum analyzer (RSA) Tektronix RSA 6114A was the signal sink with the same center frequency and an input bandwidth of 80 MHz, measurement duration of 6.5 sec with a time resolution of 110 us. The channel gain is computed based upon the emission measurement of the RSA and the time-independent reference spectrum of the VSG.

sanitization: The measurements have been performed in the presence of disturbing WLAN and Bluetooth communication. In order to eliminate the interference impact, the channel attenuation measurement repetitions are aggregated. The time variant channel gain contains five and three robot arm movement cycles for measurement M1 and M2, respectively. To eliminate the interference impact and sanitization purpose the median value was determined.

limitation: The measurements are not correlated. So, the time reference for each measurement result is randomly.

Traceset

init/robotarm/channel-gain

Time- and frequency-variant 2.4 GHz ISM band channel gain

Both traces contain a ZIP-archive of channel gain CSV-files

• file: channel-gain-M2.zip
• measurement purpose: MAC Protocol Development, Opportunistic Connectivity

init/robotarm/channel-gain Traces

• M1 : Robot arm at full-speed. Measurement are performed with the robot arm with repetition times of 1293.6 ms at 100% speed.
• format: The gain values are stored in CSV-files as floats. They are seperated by commas such as: 

-51.3,-49.1,-50.1, ....
-50.1,-48.2,-50.5, ...
    ...
The columns represent the frequency bins 2400 MHz, 2401 MHz, ... 2480 MHz. The rows represent the time instances 0 ms, 0.11 ms, 0.22 ms, ... 1293.6 ms. 
In total there are 11844 rows and 81 columns.

• M2 : Robot arm at half-speed. Measurement are performed with the robot arm with repetition times of 2105.2 ms at 50% speed. 
• format: The gain values are stored in CSV-files as floats. They are seperated by commas such as: 

-51.3,-49.1,-50.1, ....
-50.1,-48.2,-50.5, ...
    ...
The columns represent the frequency bins 2400 MHz, 2401 MHz, ... 2480 MHz. The rows represent the time instances 0 ms, 0.11 ms, 0.22 ms, ... 2105.2 ms. 
In total there are 19275 rows and 81 columns.