Technical Note: Novel method for water vapour monitoring using wireless communication networks measurements N. David1, P. Alpert1, and H. Messer2 1The Department of Geophysics and Planetary Sciences, Tel-Aviv University, Tel-Aviv, Israel 2The School of Electrical Engineering, Tel-Aviv University, Tel-Aviv, Israel
Abstract. We propose a new technique that overcomes the obstacles of the existing
methods for monitoring near-surface water vapour, by estimating humidity
from data collected through existing wireless communication networks.
Weather conditions and atmospheric phenomena affect the electromagnetic
channel, causing attenuations to the radio signals. Thus, wireless
communication networks are in effect built-in environmental monitoring
facilities. The wireless microwave links, used in these networks, are widely
deployed by cellular providers for backhaul communication between base
stations, a few tens of meters above ground level. As a result, if all
available measurements are used, the proposed method can provide moisture
observations with high spatial resolution and potentially high temporal
resolution. Further, the implementation cost is minimal, since the data used
are already collected and saved by the cellular operators. In addition –
many of these links are installed in areas where access is difficult such as
orographic terrain and complex topography. As such, our method enables
measurements in places that have been hard to measure in the past, or have
never been measured before. The technique is restricted to weather
conditions which exclude rain, fog or clouds along the propagation path.
Strong winds that may cause movement of the link transmitter or receiver (or
both) may also interfere with the ability to conduct accurate measurements.
We present results from real-data measurements taken from two microwave
links used in a backhaul cellular network that show convincing correlation
to surface station humidity measurements. The measurements were taken daily
in two sites, one in northern Israel (28 measurements), the other in central
Israel (29 measurements). The correlation between the microwave link
measurements and the humidity gauges were 0.9 and 0.82 for the north and
central sites, respectively. The Root Mean Square Differences (RMSD) were
1.8 g/m3 and 3.4 g/m3 for the northern and
central site measurements, respectively.
Citation: David, N., Alpert, P., and Messer, H.: Technical Note: Novel method for water vapour monitoring using wireless communication networks measurements, Atmos. Chem. Phys., 9, 2413-2418, doi:10.5194/acp-9-2413-2009, 2009.