Adaptive frequency‐hopping schemes for CR‐based multi‐link satellite networks. (25th March 2018)

• Record Type: Journal Article
• Authors: Aykin, Irmak; Krunz, Marwan; Xiao, Yong
• Is Part Of: International journal of satellite communications and networking. Volume 36:Number 4(2018)
• Page Start: 315
• Page End: 331
• Publication Date: 2018-03-25
• Subjects: cognitive radio -- dynamic frequency hopping -- Markov models -- maximum likelihood estimation -- out‐of‐band sensing -- satellite communications; Artificial satellites in telecommunication -- Periodicals; Digital communications -- Periodicals; 621.3825
• DOI: 10.1002/sat.1235
• Languages: English
• ISSNs: 1542-0973

Abstract

Summary: In this paper, we study two dynamic frequency hopping (DFH)–based interference mitigation approaches for satellite communications. These techniques exploit the sensing capabilities of a cognitive radio to predict future interference on the upcoming frequency hops. We consider a topology where multiple low Earth orbit satellites transmit packets to a common geostationary equatorial orbit satellite. The FH sequence of each low Earth orbit–geostationary equatorial orbit link is adjusted according to the outcome of out‐of‐band proactive sensing scheme, performed by a cognitive radio module in the geostationary equatorial orbit satellite. On the basis of sensing results, new frequency assignments are made for the upcoming slots, taking into account the transmit powers, achievable rates, and overhead of modifying the FH sequences. In addition, we ensure that all satellite links are assigned channels such that their minimum signal‐to‐interference‐plus‐noise ratio requirements are met, if such an assignment is possible. We formulate two multi‐objective optimization problems: DFH‐Power and DFH‐Rate. Discrete‐time Markov chain analysis is used to predict future channel conditions, where the number of states are inferred using k ‐means clustering, and the state transition probabilities are computed using maximum likelihood estimation. Finally, simulation results are presented to evaluate the effects of different system parameters on the performance of the proposed designs. Abstract : We study 2 DFH‐based interference mitigation approaches for SATCOM. These techniques exploit sensing capabilities of a CR to predict future interference on the upcoming frequencies. The FH sequence of each LEO‐GEO link is adjusted according to the outcome of out‐of‐band proactive sensing scheme, performed by a CR module in the GEO satellite. On the basis of sensing results, new frequency assignments are made for the upcoming slots, taking into account the transmit powers, achievable rates, and overhead of modifying the sequences.