Cognitive Zone for Broadband Satellite Communications in 17.3–17.7 GHz Band

Abstract

Deploying high throughput satellite systems in Ka band to accommodate the ever increasing demand for high data rates hits a spectrum barrier. Cognitive spectrum utilization of the allocated frequency bands to other services is a potential solution. Designing a cognitive zone around incumbent broadcasting satellite service (BSS) feeder links beyond which the cognitive fixed satellite service (FSS) terminals can freely utilize the same frequency band is considered in this paper. In addition, we show that there is a rain rate called rain wall, above which cognitive downlink communications becomes infeasible.

GEO Satellite Feeder Links and Terrestrial Full-Duplex Small Cells: A Case for Coexistence

“…1. The outdoor small cells and the satellite gateway (GW) can be geographically separated and tools provided in the paper can be used to determine the exclusion zone [6], [3] for deployment of small cells in the vicinity of GW. For simplicity, the users are assumed to be uniformly distributed in the cells and we only depict the co-channel interference between a representative small cell and the GW.…”

“…These are dependent on (a) distance of the BS (UT2) from the GW, (b) relative off-axis angles of the BS (UT2) and GW and (c) propagation impairments and antenna gains [3]. b) Internode Interference (INI): In a generic setting, UT2 suffers INI from UT1 transmissions in small cells [19].…”

“…We assume a small cell of radius of 200 metres with the BS located in the centre of the assumed circular coverage with line-of-sight channels for simplicity. Towards ease of implementation, we consider the worst-case scenario (from an interference point of view) where the offaxis angle between the GW and BS is chosen as the elevation angle at Betzdorf towards the desired satellite [3]. Towards determining the feasibility of the planned system, we evaluate the SINR in (6) for 10000 random user positions within the cell.…”

“…Equation (1) indicates that the received power at BS (in the absence of SI and noise) is |h B1 | 2 P G . Equating this to the received power at BS predicted by link analysis 3 yields the values for h B1 (and h B2 similarly). Typically, we have |h B1 | 2 ∼ −85 (in dB) and h B2 ∼ 71(in dB) 4 .…”

“…The idea of coexistence of satellite networks with other services is considered in a number of recent works [1] − [6]. These works typically deal with coexistence scenarios involving satellite downlink/ uplink and terrestrial cellular networks, [2], [6] or satellite uplink with downlink of fixedsatellite-services (FSS) [3].…”