Power and rate allocation in cognitive satellite uplink networks

Abstract

Abstract-In this paper, we consider the cognitive satellite uplink where satellite terminals reuse frequency bands of FixedService (FS) terrestrial microwave links which are the incumbent users in the Ka 27.5-29.5 GHz band. In this scenario, the transmitted power of the cognitive satellite terminals has to be controlled so as to satisfy the interference constraints imposed by the incumbent FS receivers. We investigate and analyze a set of optimization frameworks for the power and rate allocation problem in the considered cognitive satellite scenario. The main objective is to shed some light on this rather unexplored scenario and demonstrate feasibility of the terrestrial-satellite co-existence. In particular, we formulate a multi-objective optimization problem where the rates of the satellite terminals form the objective vector and derive a general iterative framework which provides a Pareto-optimal solution. Next, we transform the multi-objective optimization problem into different single-objective optimization problems, focusing on popular figures of merit such as the sumrate or the rate fairness. Supporting results based on numerical simulations are provided which compare the different proposed approaches.

Optimal Power Control in Cognitive Satellite Terrestrial Networks With Imperfect Channel State Information

“…In the uplink case, a novel power control scheme was presented to maximize the ergodic capacity of the satellite user in [7], where the terrestrial cellular system served as the primary system. When the fixed-service terrestrial microwave system operated as the primary system, the power allocation scheme was proposed for the fixed satellite service system in [8]. Considering the delay-sensitive service, two optimal power control schemes were presented in [9], which optimized the delay-limited capacity and outage capacity, respectively.…”

“…The free space loss of the secondary link and interference link are denoted as L s and L p , respectively. G t (θ) corresponds to the transmit antenna gain at the satellite user for secondary link, which can be obtained as [8]…”

Signal Processing for High-Throughput Satellites: Challenges in New Interference-Limited Scenarios

“…Here, we focus on the most common one of interest to the satellite industry, that is, maximizing the system throughput or sum-rate. Works such as [48] consider other objective functions as well, such as multi-objective, max-min, and proportional fairness. Furthermore, in this paper, we only focus on the case a single satellite operator; extension of cognitive access to the case of multiple operators with limited information exchange is a challenge with potential for future studies.…”

Optimal Power Control for Real-time Applications in Cognitive Satellite Terrestrial Networks

“…Considering the uplink case, novel 42 resource allocation schemes are proposed in [6], [7], where 43 the terrestrial cellular system and fixed-service terrestrial 44 microwave system serve as the primary networks, respectively. 45 Nevertheless, these existing methods do not consider the real-46 time applications over practical propagation channels, which 47 may require a constant rate transmission over all the fading 48 blocks.…”

“…optimal power control scheme can be formulated as [8] can be obtained as [7] 141 . 152 G r,max represents the maximum gain at the onboard antenna 153 boresight, ϕ is the angle between the satellite user and the 154 antenna boresight, and ϕ 3dB is the 3-dB angle [1] [12].…”