Auction Based Spectrum Management
of Cognitive Radio Networks
Advisor ：Wei-Yeh Chen
Student ：楊
于
世

Reference

H. B. Chang, K. C. Chen, N. R. Prasad and C. W. Su, “Auction
Based Spectrum Management of Cognitive Radio Networks,”
in Proc. IEEE VTC, Barcelona, Spain, pp. 1-5, April 2009.
1
Outline

Introduction

Four parties

Vickrey auction

System Model

Management Policy

Simulation Result

Conclusion
2
Introduction

Due to the increasing demand for spectrum dramatically(引人
注意的) and underutilization of spectrum, dynamic spectrum
access (DSA) for cognitive radios (CRs) is proposed to resolve
the challenge of insufficient(未充分) spectrum usage.

To facilitate(促進) dynamic spectrum sharing, spectrum
management with appropriate(適當的) economic model would
be required for four involved parties in this scenario.
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Four parties (characters)

The spectrum regulator：general public interests.

The service provider (PS-BS)：operator.

PRN users (PS-MSs)：license users or primary users.

CR-MSs：secondary users.
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Parties expect

The spectrum regulator wishes to fully utilize spectrum bands.

The service provider wishes to increase his profit (by
increasing revenue) with limited spectrum bands by allowing
CRs to access the spectrum bands.

The PRN users wishes to share the increasing profit of the
service provider.

CR-MSs wish to increase opportunity of accessing spectrum
bands with surely less pay to utilize spectrum.
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Vickrey auction

The Vickrey auction can also allocate unused spectrum bands
to CR-MSs faster, more efficient than traditional English
auction in a limited time and meet economic efficiency.

Thus we adopt the Vickrey auction for CR-MSs in our
spectrum management policy study.
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System Model

Network Topology

Traffic Model

Pricing Model

Compensating Mechanism Model
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Network Topology
The network topology of the CRN
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Traffic Model(1/2)
A super frame
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Traffic Model(2/2)

PR-MSs：If any spectrum band is free, PS-MSs can access
them in any control or data frame.

CR-MSs：We only allow CR-MSs to compete in spectrum
bands at the first time slot of one control frame and can utilize
the spectrum bands with a superframe time without any
spectrum handoff.
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Pricing Model

In our network topology, we have two kinds of users which are
PS-MSs and CR-MSs.

The service provider charges the price of PS-MSs and CRMSs at a rate QP and QCR per control or data frame time
respectively.
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Compensating Mechanism Model

In our system model, the only interference which CR-MSs
may make to PS-MS is blocking.

We measure the interference by using the number of
blocking data frames (denoted as B) due to the occupation
of the CR-MSs.
Pro = RP(QP)＋RC(QCR)－QC(B)
Pro： The profit of the service provider
QC(B)：The PR-MSs as compensation per control or data frame
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Management Policy(1/3)

(1) At the beginning of the control frame, there are Np(D) PSMSs which come from the period of the Dth data frame and
attempt to utilize the spectrum bands.
 (a) If Np(D) > K , K spectrum bands are first allocated to
the K of Np(D) PS-MSs and the number of the remaining
unused spectrum bands (denote it as M) is zero (i.e., M = 0).

(b) Otherwise, Np(D) spectrum bands are first allocated to
the PS-MSs and M = Np(D) − K .
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Management Policy(2/3)

If M ≠ 0 , the PS-BS announces(宣佈) an auction process.
Otherwise, the PS-BS would not broadcast any information to
the CR-MSs.

We reasonably assume that the auction process can be finished
in one control frame. The auction process consists of three
processes: Announcing, Bidding, and Permitting.
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Management Policy(3/3)

CR-MSs with higher submitted(屈服) bids D data frames to
utilize without any spectrum handoff.

The CR-MSs which utilize the M spectrum bands would
not interfere with PS-MSs.

Otherwise, the CR-MSs would interfere with PS-MSs. The
service provider compensates the operating interference
from CR-MSs to the PS-MSs.
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Simulation Result

In our proposed compensation mechanism, if the PS-MSs are
interfered with one data frame by CR-MSs.

PS-MSs can be free to utilize one data frame and the PS-MSs
have higher priority to utilize the spectrum bands in the next
data frame.

Consequently, we obtain the mean of the profit for service
provider per super frame time in our example.
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Mean profit per super frame time
17
The incremental profit by CR-MSs
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Spectrum utilization with CR-MSs
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Conclusion

本篇論文主要提出四個群體，來探討每個群體之間的利益
關係，並提出拍賣的流程及補償機制，對未來要研究拍賣
的議題有實質上的幫助。
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