Enforcement and Spectrum Sharing: Case Studies of Federal-Commercial Sharing

To promote economic growth and unleash the potential of wireless broadband, there is a need to introduce more spectrally efficient technologies and spectrum management regimes. That led to an environment where commercial wireless broadband need to share spectrum with the federal and non-federal operations. Implementing sharing regimes on a non-opportunistic basis means that sharing agreements must be implemented. To have meaning, those agreements must be enforceable.\ud \ud With the significant exception of license-free wireless systems, commercial wireless services are based on exclusive use. With the policy change facilitating spectrum sharing, it becomes necessary to consider how sharing might take place in practice. Beyond the technical aspects of sharing, that must be resolved lie questions about how usage rights are appropriately determined and enforced. This paper is reasoning about enforcement in a particular spectrum bands (1695-1710 MHz and 3.5 GHz) that are currently being proposed for sharing between commercial services and incumbent spectrum users in the US. We examine three enforcement approaches, exclusion zones, protection zones and pure ex post and consider their implications in terms of cost elements, opportunity cost, and their adaptability

Valuing Spectrum Allocations

Observing trends in which Wi-Fi and Bluetooth have become widely popular, some argue that unlicensed allocations hosting such wireless technologies are increasingly valuable and that administrative spectrum allocations should shift accordingly. We challenge that policy conclusion. A core issue is that the social value of a given spectrum allocation is widely assumed to equal the gains of the applications it is likely to host. This thinking is faulty, as vividly seen in what we deem the Broadcast TV Spectrum Valuation Fallacy – the idea that because wireless video, or broadcast network programs are popular, TV channels are efficiently defined. This approach has been appropriately rejected, in key instances, by spectrum regulators, but is similarly applied in other instances regarding unlicensed allocations. While traditional allocations have garnered widespread criticism for imposing rigid barriers tending to block innovation, and flexible-use spectrum access rights have gained favor, the regulatory methods used to allocate (or reallocate) bandwidth remain embedded in a “command and control” process. Reconfiguring spectrum usage to enable emerging wireless markets often requires lengthy, costly rule makings. The expense of this administrative overhead is generally omitted from spectrum allocation policy analysis. Yet, it constitutes an essential component of the consumer welfare analysis. We propose a more fulsome policy approach, one that includes not only the appropriate measures of marginal value and opportunity cost for rival allocations, but incorporates transaction costs. Instead of regulators attempting to guess how much bandwidth should be allocated to various types of licensed and unlicensed services – and imposing different rules within and across these allocations – a more generic approach is called for. By better enabling spontaneous adjustments to changing consumer demands and technological innovation, spectrum allocations can be more efficiently brought into their most valuable employments

Enforcement in Dynamic Spectrum Access Systems

The spectrum access rights granted by the Federal government to spectrum users come with the expectation of protection from harmful interference. As a consequence of the growth of wireless demand and services of all types, technical progress enabling smart agile radio networks, and on-going spectrum management reform, there is both a need and opportunity to use and share spectrum more intensively and dynamically. A key element of any framework for managing harmful interference is the mechanism for enforcement of those rights. Since the rights to use spectrum and to protection from harmful interference vary by band (licensed/unlicensed, legacy/newly reformed) and type of use/users (primary/secondary, overlay/underlay), it is reasonable to expect that the enforcement mechanisms may need to vary as well.\ud \ud In this paper, we present a taxonomy for evaluating alternative mechanisms for enforcing interference protection for spectrum usage rights, with special attention to the potential changes that may be expected from wider deployment of Dynamic Spectrum Access (DSA) systems. Our exploration of how the design of the enforcement regime interacts with and influences the incentives of radio operators under different rights regimes and market scenarios is intended to assist in refining thinking about appropriate access rights regimes and how best to incentivize investment and growth in more efficient and valuable uses of the radio frequency spectrum

Valuing Spectrum Allocations

Observing trends in which Wi-Fi and Bluetooth have become widely popular, some argue that unlicensed allocations hosting such wireless technologies are increasingly valuable and that administrative spectrum allocations should shift accordingly. We challenge that policy conclusion. A core issue is that the social value of a given spectrum allocation is widely assumed to equal the gains of the applications it is likely to host. This thinking is faulty, as vividly seen in what we deem the Broadcast TV Spectrum Valuation Fallacy – the idea that because wireless video, or broadcast network programs are popular, TV channels are efficiently defined. This approach has been appropriately rejected, in key instances, by spectrum regulators, but is similarly applied in other instances regarding unlicensed allocations. While traditional allocations have garnered widespread criticism for imposing rigid barriers tending to block innovation, and flexible-use spectrum access rights have gained favor, the regulatory methods used to allocate (or reallocate) bandwidth remain embedded in a “command and control” process. Reconfiguring spectrum usage to enable emerging wireless markets often requires lengthy, costly rule makings. The expense of this administrative overhead is generally omitted from spectrum allocation policy analysis. Yet, it constitutes an essential component of the consumer welfare analysis. We propose a more fulsome policy approach, one that includes not only the appropriate measures of marginal value and opportunity cost for rival allocations, but incorporates transaction costs. Instead of regulators attempting to guess how much bandwidth should be allocated to various types of licensed and unlicensed services – and imposing different rules within and across these allocations – a more generic approach is called for. By better enabling spontaneous adjustments to changing consumer demands and technological innovation, spectrum allocations can be more efficiently brought into their most valuable employments

Review on Radio Resource Allocation Optimization in LTE/LTE-Advanced using Game Theory

Recently, there has been a growing trend toward ap-plying game theory (GT) to various engineering fields in order to solve optimization problems with different competing entities/con-tributors/players. Researches in the fourth generation (4G) wireless network field also exploited this advanced theory to overcome long term evolution (LTE) challenges such as resource allocation, which is one of the most important research topics. In fact, an efficient de-sign of resource allocation schemes is the key to higher performance. However, the standard does not specify the optimization approach to execute the radio resource management and therefore it was left open for studies. This paper presents a survey of the existing game theory based solution for 4G-LTE radio resource allocation problem and its optimization

Combining Spot and Futures Markets: A Hybrid Market Approach to Dynamic Spectrum Access

Dynamic spectrum access is a new paradigm of secondary spectrum utilization and sharing. It allows unlicensed secondary users (SUs) to exploit opportunistically the under-utilized licensed spectrum. Market mechanism is a widely-used promising means to regulate the consuming behaviours of users and, hence, achieves the efficient allocation and consumption of limited resources. In this paper, we propose and study a hybrid secondary spectrum market consisting of both the futures market and the spot market, in which SUs (buyers) purchase under-utilized licensed spectrum from a spectrum regulator, either through predefined contracts via the futures market, or through spot transactions via the spot market. We focus on the optimal spectrum allocation among SUs in an exogenous hybrid market that maximizes the secondary spectrum utilization efficiency. The problem is challenging due to the stochasticity and asymmetry of network information. To solve this problem, we first derive an off-line optimal allocation policy that maximizes the ex-ante expected spectrum utilization efficiency based on the stochastic distribution of network information. We then propose an on-line VickreyCClarkeCGroves (VCG) auction that determines the real-time allocation and pricing of every spectrum based on the realized network information and the pre-derived off-line policy. We further show that with the spatial frequency reuse, the proposed VCG auction is NP-hard; hence, it is not suitable for on-line implementation, especially in a large-scale market. To this end, we propose a heuristics approach based on an on-line VCG-like mechanism with polynomial-time complexity, and further characterize the corresponding performance loss bound analytically. We finally provide extensive numerical results to evaluate the performance of the proposed solutions.Comment: This manuscript is the complete technical report for the journal version published in INFORMS Operations Researc

Iris: Deep Reinforcement Learning Driven Shared Spectrum Access Architecture for Indoor Neutral-Host Small Cells

We consider indoor mobile access, a vital use case for current and future mobile networks. For this key use case, we outline a vision that combines a neutral-host based shared small-cell infrastructure with a common pool of spectrum for dynamic sharing as a way forward to proliferate indoor small-cell deployments and open up the mobile operator ecosystem. Towards this vision, we focus on the challenges pertaining to managing access to shared spectrum (e.g., 3.5GHz US CBRS spectrum). We propose Iris, a practical shared spectrum access architecture for indoor neutral-host small-cells. At the core of Iris is a deep reinforcement learning based dynamic pricing mechanism that efficiently mediates access to shared spectrum for diverse operators in a way that provides incentives for operators and the neutral-host alike. We then present the Iris system architecture that embeds this dynamic pricing mechanism alongside cloud-RAN and RAN slicing design principles in a practical neutral-host design tailored for the indoor small-cell environment. Using a prototype implementation of the Iris system, we present extensive experimental evaluation results that not only offer insight into the Iris dynamic pricing process and its superiority over alternative approaches but also demonstrate its deployment feasibility

Applications of Repeated Games in Wireless Networks: A Survey

A repeated game is an effective tool to model interactions and conflicts for players aiming to achieve their objectives in a long-term basis. Contrary to static noncooperative games that model an interaction among players in only one period, in repeated games, interactions of players repeat for multiple periods; and thus the players become aware of other players' past behaviors and their future benefits, and will adapt their behavior accordingly. In wireless networks, conflicts among wireless nodes can lead to selfish behaviors, resulting in poor network performances and detrimental individual payoffs. In this paper, we survey the applications of repeated games in different wireless networks. The main goal is to demonstrate the use of repeated games to encourage wireless nodes to cooperate, thereby improving network performances and avoiding network disruption due to selfish behaviors. Furthermore, various problems in wireless networks and variations of repeated game models together with the corresponding solutions are discussed in this survey. Finally, we outline some open issues and future research directions.Comment: 32 pages, 15 figures, 5 tables, 168 reference