Potential interference and rain attenuation at 21.4–22 GHz downlink broadcasting satellite signals

Abstract

World Radio Conference WRC-1992 has allocated the frequency band 21.4-22.0 GHz to regions 1 and 3 to be utilised to carry direct broadcasting satellite (DBS) services. This high-frequency band is more susceptible to rain attenuation, leading to degradation of the signal quality. Moreover, this frequency band is assigned to two different services, i.e. satellite broadcasting and fixed mobile services at the same regions; hence, the impact of intersystem interference in a depredated signal is a critical issue in the DBS receiver. In this study, the effects of rain attenuation on the DBS downlink signals as well as the impact of the potential interference on the reception quality will be estimated. An interference scenario will be introduced to investigate the system performance in both propagation mechanisms of clear-sky and rain conditions.

Performance of the DBS Satellite Receiver under the Impact of Rainfall and Terrestrial Interference

“…A number of publications reported the research in the field of concurrently operating the terrestrial fixed service (FS) with satellite services (SS) (broadcasting (BSS) and fixed (FSS)), in different spectrum frequency bands [4,[7][8][9][10][11][12][13][14][15][16][17][18]. Most researches mainly study the performance of satellite receiver affected by the FS system based on spectrum sharing policies between the dissimilar systems.…”

“…On the other hand, the studies which have considered the impact of rain on operating of the satellite service and FS were reported in [1,4,7] which have been carried out in frequencies higher than 10 GHz. The frequencies above 10 GHz are influenced by rain attenuation while the lower frequencies than 6 GHz are not seriously affected by rain attenuation.…”

“…In terms of rainfall intensity, it can be seen that the study in [8] discusses the intersystem interference in Greece as a Mediterranean region, while the research in [4] investigated the spectrum sharing operation of the satellite and FS services in the tropical region as a heavy rain area. Moreover, the work in [7] studied the satellite and FS services in the semiarid conditions.…”

“…(a) In the current paper, the thermal noise of the DBS receiver has been taken into account, so this study uses the carrier-to-noise plus interference ratio (CNIR) criteria, while in [7], the criterion was different, carrierto-interference ratio (CIR), as the receiver noise in [7] was not considered. This makes the current paper more technically sound (b) The CIR criterion value in [7] is 23 dB, while this study uses a CNIR of 4.7 dB which adds more restrictions on the receiver ability to pick up the satellite signal (c) The study in [4] uses the rain attenuation link budget and the research in [7] applies the rain rate exceedance of 0.01% which does not always occur.…”

“…In those bands, attenuation due to rain represents a dominant factor that reduces the system availability and negatively affects its performance especially in heavy rain areas such as in south Saudi Arabia. Thus, the rain attenuation impacts higher frequency bands and it is more harmful than that in the lower bands [3,4]. According to ITU-R, the 21.4-22 GHz band has been allocated to 3 dissimilar services: fixed, mobile, and satellite broadcasting services in the 1 st and 3 rd regions including Saudi Arabia which is considered as a semiarid area.…”