Low-Cost Ka-Band Satellite Receiver Data Preprocessing for Tropospheric Propagation Studies

Abstract

Satellite tropospheric propagation studies strongly rely on beacon receiver measurements. We were interested in performing a measurement campaign to characterize rain attenuation statistics. In this article, we outline some of the characteristics and drawbacks one faces when trying to perform a radio wave satellite beacon propagation experiment at the Ka-band with low-cost measurement equipment. We used an affordable beacon receiver consisting of a commercial low-noise block down-converter, an outdoor dual-reflector antenna, and a software-defined radio unit. To measure rain attenuation events, we needed to work out where the reference signal level was at all times. However, as we did not have a radiometer to remove the impact of gases and clouds, since it is a very expensive device, we used a procedure that involved the subtraction of a stable and reliable reference level (template) from the raw received beacon level. This template was extracted from observations during non-rainy periods. The procedure implemented for extracting the template was based on the same data processing methodology used by other authors in this field. Here, we describe through specific examples the main characteristics of the templates extracted on non-rainy days, as well as the impact of some meteorological parameters and unavoidable, but small antenna pointing errors.

Special Issue “Rain Sensors”

“…Pastoriza-Santos et al [ 25 ] experimentally outline some of the characteristics and drawbacks affecting the propagation of a radio beacon in Ka-band from a GEO satellite to a ground-based measurement equipment, made of low-cost commercial-grade devices, as in case of SML-based opportunistic rain sensing. The paper describes a procedure for evaluating and subtracting the baseline level corresponding to no-rain conditions from the raw received beacon signal.…”

Rainfall Map from Attenuation Data Fusion of Satellite Broadcast and Commercial Microwave Links

“…Recently, a significant research effort has been devoted also to the estimation of the rainfall rate from the received signal level at the ground station of direct-to-home (DTH) broadcast satellite links (BSLs) [14][15][16][17][18][19][20]. Hence, taking advantage of the limited cost and ease of installation of the commercial-grade BSL receivers for DTH broadcast, the rationale of our current work consists of effectively merging together the attenuation data coming from both the CML and BSL receivers.…”