Inline Interference Mitigation Techniques for Spectral Coexistence of GEO and NGEO Satellites

Abstract

The requirement of low latency for real time systems and high demand of broadband data are leading to the rapid deployment of Low Earth Orbit (LEO)/Medium Earth Orbit (MEO) satellite systems in several frequency bands. When the number of usable non-geostationary (NGEO) satellites i.e., LEO/MEO in space increases, the need for frequency coexistence between the NGEO satellite systems with the already existing geostationary (GEO) satellite networks increases rapidly. In this context, it is crucial to explore interference mitigation techniques between GEO and NGEO systems in order to allow their spectral coexistence. More specifically, in the coexistence scenario of GEO and NGEO satellite networks, in-line interference may be a serious problem and it arises whenever an NGEO satellite passes through a line of sight path between a GEO earth station and a GEO satellite. In this paper, we carry out interference analysis between GEO and NGEO systems considering the case of O3b satellite systems and propose an adaptive power control technique for both the uplink and the downlink coexistence scenarios in order to mitigate the in-line interference. Furthermore, we provide several cognitive solutions for mitigating the in-line interference.

Physical layer aspects of wireless IoT

“…In order to address the spectrum scarcity problem, the concept of cognitive radio is getting an important attention in SatCom [27]. Various techniques such as beamforming, power allocation, and carrier allocation have been studied considering the coexistence of satellite and terrestrial systems [28] and two satellite systems [29].…”

Cognitive dual satellite systems

“…The link budget is modeled using the standard methods as in [34] which has been extended to two satellites [15]. Using the notation in Table 12.2, the received power at the ST2 earth station, P rst2 , can be written as :…”

“…The scenario has been shown in Figure 12.2(b) and has been extensively discussed in [15]. The scenario has been shown in Figure 12.2(b) and has been extensively discussed in [15].…”

“…The interference aligned across v can be removed using zero-forcing filter. The interference mitigation is tackled by formulating optimization problems for uplink and downlink separately [15]. (b) Coordinated IA: Adding more amount of cognition to IA leads to coordinated IA, where the primary and secondary systems coordinate to exchange CSI information and the alignment vector dynamically depending on best conditions.…”

Implementation Issues of Cognitive Radio techniques for Ka-band (17.7–19.7 GHz) SatComs

“…Examples include Co 2 Sat (Cooperative and Cognitive Architectures for Satellite Networks) [3,8], ACROSS (Applicability of CR to Satellite Systems) [9], CoRaSat (CR for SatComs) [4], etc. Existing literature related to the cognitive SatComs can be categorised into [7]: (i) hybrid satellite-terrestrial coexistence [3,4,9], and (ii) dual satellite coexistence scenario [8,10,11].…”