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Equilibrium and Disequilibrium Pricing for Spectrum Trading in Cognitive Radio: A Control-Theoretic Approach. Advisor : Wei-Yeh Chen Student :楊 于 世 Reference
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Equilibrium and Disequilibrium Pricing forSpectrum Trading in Cognitive Radio: AControl-Theoretic Approach Advisor :Wei-Yeh Chen Student:楊 于 世 • Reference • D. Niyato , E. Hossain, “Equilibrium and Disequilibrium Pricing for Spectrum Trading in Cognitive Radio: A Control- Theoretic Approach,” in GLOBECOM Washington DC, pp. 4852 - 4856 , Nov. 2007 .
Outline • Introduction • System model • Spectrum supply and demand functions • Pricing for spectrum trading • Performance diagram • Conclusion
Introduction(1/2) • Spectrum trading is a concept used to describe the economics of dynamic spectrum sharing in cognitive radio networks. • In this paper, we model and analyze spectrum trading in a cognitive radio environment, where the primary service (i.e., spectrum owner) shares the spectrum with the secondary services (i.e., spectrum buyers).
Introduction(2/2) • In spectrum trading, an equilibrium price is required to satisfy all of the entities in the market. • We consider the disequilibrium case where the spectrum price does not conform(遵守) to the market equilibrium.
System model • Primary and Secondary Services • Spectrum Trading Model
Primary and Secondary Services • We consider a wireless system with a single primary service operating on multiple frequency spectrum. • The primary service serves NP,i local connections using the frequency spectrum Fi which is of size Wi.
Spectrum Trading Model • The price of spectrum in each market depends on the spectrum supply from the primary service and the demand from the secondary service. • The primary service/user may not be fully utilized, and the primary service may want to exploit(利用) this spectrum underutilization(未充分使用) and sell the spectrum opportunities to secondary service(s).
Spectrum supply and demand functions • Primary Service: Profit and Spectrum Supply • Secondary Service:Utility and Spectrum Demand
Pricing for spectrum trading • Equilibrium Pricing • Disequilibrium Pricing
Equilibrium Pricing • In this model, the price is used to determine spectrum supply and demand for the primary and the secondary services, respectively. • The difference between spectrum demand and supply is then fed back to adjust the price. • The price of one frequency band affects the demand for another frequency band.
P:Price S:Supply D:Demand λ:Control parameter Block diagram of the equilibrium pricing control system.
Disequilibrium Pricing • The price of spectrum F2 is set to a value which does not conform to the equilibrium. • In this case, the excess demand for F2 is aggregated(聚集) with that of spectrum F1.
Step response of equilibrium prices under disequilibrium condition.
Conclusion • 頻譜交易中,平衡與非平衡的概念,在這些機制中,加入控制參數後,去調整價格,讓市場能達到平衡,使主要頻譜的擁有者能得到最佳的利益,次要使用者得到最佳的頻譜服務品質。