Spectrum sensing apparatus and method for cooperative cognitive radio network in non-gaussian noise environment, and fusion center apparatus and cooperative cognitive radio system using the same

Patent metadata

Field	Value
Publication number	US-9628996-B2
Application number	US-201414518181-A
Country	US
Kind code	B2
Filing date	Oct 20, 2014
Priority date	Oct 18, 2013
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

Disclosed herein are a spectrum sensing apparatus and method for a cognitive radio (CCR) network in a non-Gaussian noise environment and an FC apparatus and CCR system using the same. The cooperative cognitive radio (CCR) system includes M cognitive radios (CRs), and a fusion center (FC). Each of the M CRs samples a baseband signal obtained by down-converting a radio signal detected in the corresponding frequency spectrum, and generates spectrum sensing information (SSI) indicating that a PU signal has been detected based on the results of the sampling. The FC determines a joint threshold λ FC that can maximize an expected average throughput of a secondary user (SU) signal in a given communication environment including a maximum interference condition, calculates a joint test statistic from received M pieces of SSI, and determines whether the PU signal is present by comparing the calculated joint test statistic with the joint threshold.

First claim

What is claimed is:

1. A cooperative cognitive radio (CCR) apparatus, comprising:
M cognitive radios (CRs), each CR configured to sample a baseband signal and to determine whether a primary user (PU) is currently occupying a frequency spectrum band assigned to the PU, and to generate spectrum sensing information (SSI) indicating that a PU signal has been detected based on the sampling;
a fusion center (FC) configured to determine a joint threshold λ FC that can maximize an expected average throughput of a secondary user (SU) signal in a given communication environment including a maximum interference condition, to calculate a joint test statistic from M pieces of SSI received from the respective M CRs when receiving the M pieces of SSI from the respective M CRs, and to determine whether the PU signal is present by comparing the calculated joint test statistic with the joint threshold λ FC ;
a PU signal determiner configured to receive the M pieces of SSI from the respective M CRs, and to determine whether the PU signal is present based on the joint test statistic; and
a threshold optimizer configured to:
determine the joint threshold λ FC that can maximize an expected average throughput of the SU signal based on a given communication environment including a maximum interference condition; and
determine the joint threshold λ FC to be 1 and a corresponding counting rule to be an OR rule, or to determine the joint threshold λ FC to be M and a corresponding counting rules to be an AND rule, based on the given maximum interference condition.

2. The CCR apparatus of claim 1 , wherein the threshold optimizer is further configured to determine the joint threshold λ FC to be a value that can maximize the expected average throughput of the SU signal based on a given maximum interference condition, the number of CRs, a false alarm probability, a detection probability, the designed throughput of the SU signal, and the magnitude of interference imposed on a PU signal by the SU signal.

3. The CCR apparatus of claim 2 , wherein the threshold optimizer is further configured to determine the joint threshold λ FC to be a value that satisfies the following equation:

max
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where p fa is a false alarm probability of any one CR, p d is a detection probability of the CR, R is the designed throughput of the SU signal, x is the number of CRs that belong to the M CRs and also detect the PU signal, M C M-x is a combination indicative of the number of cases where M-x CRs are selected from among the M CRs, C is the magnitude of interference that the SU signal imposes upon the PU signal, and ε is a given maximum interference magnitude condition.

4. The CCR apparatus of claim 1 , wherein the FC further comprises:
a dynamic band manager configured to continuously manage information about a band in which a PU signal is present and an empty band throughout overall spectrum, and to perform control depending on a band use request from an SU and a determination of whether the PU signal is present so that the empty band is assigned to the SU or a band that is being use by the SU is withdrawn or changed.

5. The CCR apparatus of claim 1 , wherein the CR comprises a spectrum sensor configured to generate the SSI indicating that the PU signal has been detected based on results of the sampling; and
wherein the spectrum sensor further comprises:
a sampler configured to sample the received baseband signal, and to generate an observation vector y m =(y m (1), y m (2), . . . , y m (N)) (m is an integer that satisfies 1≦m≦M) composed of N sampled observations;
an observatio

Assignees

• Univ Sungkyunkwan Res & Bus

Inventors

• Chae Keun Hong
• Yoon Seok Ho

Classifications

• H04W16/14 Primary

  Spectrum sharing arrangements {between different networks} · CPC title

• H04W72/00 Primary

  Local resource management · CPC title