Please use this identifier to cite or link to this item:

`http://localhost/handle/Hannan/522334`

Title: | Joint Subchannel Assignment and Power Allocation for OFDMA Femtocell Networks |

Authors: | Sch. of Electr. Eng. & Comput. Sci., Univ. of Newcastle, Newcastle, NSW, Australia;Duy Trong Ngo ; Khakurel, Suman ; Tho Le-Ngoc |

subject: | OFDM modulation; approximation theory; convex programming; femtocellular radio; geometric programming; AGM approximation-based solution; DC approximation-based solutions; FUE; OFDM subchannels; OFDMA femtocell networks; SCA-based power optimization solutions; SINR; arithmetic-geometric mean approximation based solution; base stations; convex relaxation programs; femtocell user equipments; geometric programming; iterative approach; joint subchannel and power allocation algorithm; network capacity; nonconvex power allocation problem; orthogonal frequency-division multiple access mixed femtocell-macrocell network deployment; signal-to-interference-plus-noise ratio; subchannel assignment; successive convex approximation approach; Approximation methods; Interference; Joints; Macrocell networks; OFDM; Resource management; Signal to noise ratio; Convex optimization; femtocell; heterogeneous networks; iterative algorithm; macrocell QoS protection; power allocation; subchannel assignment; successive convex approximation; |

Year: | 2014 |

Publisher: | IEEE |

Abstract: | In this paper, we propose a joint subchannel and power allocation algorithm for the downlink of an orthogonal frequency-division multiple access (OFDMA) mixed femtocell/macrocell network deployment. Specifically, the total throughput of all femtocell user equipments (FUEs) is maximized while the network capacity of an existing macrocell is always protected. Towards this end, we employ an iterative approach in which OFDM subchannels and transmit powers of base stations (BS) are alternatively assigned and optimized at every step. For a fixed power allocation, we prove that the optimal policy in each cell is to give each subchannel to the user with the highest signal-to-interference-plus-noise ratio (SINR) on that subchannel. For a given subchannel assignment, we adopt the successive convex approximation (SCA) approach and transform the highly nonconvex power allocation problem into a sequence of convex subproblems. In the arithmetic-geometric mean (AGM) approximation, we apply geometric programming to find optimal solutions after condensing a posynomial into a monomial. On the other hand, logarithmic and underline{d}ifference-of-two-underline{c}oncave-functions (D.C.) approximations lead us to solving a series of convex relaxation programs. With the three proposed SCA-based power optimization solutions, we show that the overall joint subchannel and power allocation algorithm converges to some local maximum of the original design problem. While a central processing unit is required to implement the AGM approximation-based solution, each BS locally computes the optimal subchannel and power allocation for its own servicing cell in the logarithmic and D.C. approximation-based solutions. Numerical examples confirm the merits of the proposed algorithm. |

URI: | http://localhost/handle/Hannan/280935 http://localhost/handle/Hannan/522334 |

ISSN: | 1536-1276 |

volume: | 13 |

issue: | 1 |

Appears in Collections: | 2014 |

Files in This Item:

File | Size | Format | |
---|---|---|---|

6678362.pdf | 859.78 kB | Adobe PDF |

Title: | Joint Subchannel Assignment and Power Allocation for OFDMA Femtocell Networks |

Authors: | Sch. of Electr. Eng. & Comput. Sci., Univ. of Newcastle, Newcastle, NSW, Australia;Duy Trong Ngo ; Khakurel, Suman ; Tho Le-Ngoc |

subject: | OFDM modulation; approximation theory; convex programming; femtocellular radio; geometric programming; AGM approximation-based solution; DC approximation-based solutions; FUE; OFDM subchannels; OFDMA femtocell networks; SCA-based power optimization solutions; SINR; arithmetic-geometric mean approximation based solution; base stations; convex relaxation programs; femtocell user equipments; geometric programming; iterative approach; joint subchannel and power allocation algorithm; network capacity; nonconvex power allocation problem; orthogonal frequency-division multiple access mixed femtocell-macrocell network deployment; signal-to-interference-plus-noise ratio; subchannel assignment; successive convex approximation approach; Approximation methods; Interference; Joints; Macrocell networks; OFDM; Resource management; Signal to noise ratio; Convex optimization; femtocell; heterogeneous networks; iterative algorithm; macrocell QoS protection; power allocation; subchannel assignment; successive convex approximation; |

Year: | 2014 |

Publisher: | IEEE |

Abstract: | In this paper, we propose a joint subchannel and power allocation algorithm for the downlink of an orthogonal frequency-division multiple access (OFDMA) mixed femtocell/macrocell network deployment. Specifically, the total throughput of all femtocell user equipments (FUEs) is maximized while the network capacity of an existing macrocell is always protected. Towards this end, we employ an iterative approach in which OFDM subchannels and transmit powers of base stations (BS) are alternatively assigned and optimized at every step. For a fixed power allocation, we prove that the optimal policy in each cell is to give each subchannel to the user with the highest signal-to-interference-plus-noise ratio (SINR) on that subchannel. For a given subchannel assignment, we adopt the successive convex approximation (SCA) approach and transform the highly nonconvex power allocation problem into a sequence of convex subproblems. In the arithmetic-geometric mean (AGM) approximation, we apply geometric programming to find optimal solutions after condensing a posynomial into a monomial. On the other hand, logarithmic and underline{d}ifference-of-two-underline{c}oncave-functions (D.C.) approximations lead us to solving a series of convex relaxation programs. With the three proposed SCA-based power optimization solutions, we show that the overall joint subchannel and power allocation algorithm converges to some local maximum of the original design problem. While a central processing unit is required to implement the AGM approximation-based solution, each BS locally computes the optimal subchannel and power allocation for its own servicing cell in the logarithmic and D.C. approximation-based solutions. Numerical examples confirm the merits of the proposed algorithm. |

URI: | http://localhost/handle/Hannan/280935 http://localhost/handle/Hannan/522334 |

ISSN: | 1536-1276 |

volume: | 13 |

issue: | 1 |

Appears in Collections: | 2014 |

Files in This Item:

File | Size | Format | |
---|---|---|---|

6678362.pdf | 859.78 kB | Adobe PDF |

Title: | Joint Subchannel Assignment and Power Allocation for OFDMA Femtocell Networks |

Authors: | Sch. of Electr. Eng. & Comput. Sci., Univ. of Newcastle, Newcastle, NSW, Australia;Duy Trong Ngo ; Khakurel, Suman ; Tho Le-Ngoc |

subject: | OFDM modulation; approximation theory; convex programming; femtocellular radio; geometric programming; AGM approximation-based solution; DC approximation-based solutions; FUE; OFDM subchannels; OFDMA femtocell networks; SCA-based power optimization solutions; SINR; arithmetic-geometric mean approximation based solution; base stations; convex relaxation programs; femtocell user equipments; geometric programming; iterative approach; joint subchannel and power allocation algorithm; network capacity; nonconvex power allocation problem; orthogonal frequency-division multiple access mixed femtocell-macrocell network deployment; signal-to-interference-plus-noise ratio; subchannel assignment; successive convex approximation approach; Approximation methods; Interference; Joints; Macrocell networks; OFDM; Resource management; Signal to noise ratio; Convex optimization; femtocell; heterogeneous networks; iterative algorithm; macrocell QoS protection; power allocation; subchannel assignment; successive convex approximation; |

Year: | 2014 |

Publisher: | IEEE |

Abstract: | In this paper, we propose a joint subchannel and power allocation algorithm for the downlink of an orthogonal frequency-division multiple access (OFDMA) mixed femtocell/macrocell network deployment. Specifically, the total throughput of all femtocell user equipments (FUEs) is maximized while the network capacity of an existing macrocell is always protected. Towards this end, we employ an iterative approach in which OFDM subchannels and transmit powers of base stations (BS) are alternatively assigned and optimized at every step. For a fixed power allocation, we prove that the optimal policy in each cell is to give each subchannel to the user with the highest signal-to-interference-plus-noise ratio (SINR) on that subchannel. For a given subchannel assignment, we adopt the successive convex approximation (SCA) approach and transform the highly nonconvex power allocation problem into a sequence of convex subproblems. In the arithmetic-geometric mean (AGM) approximation, we apply geometric programming to find optimal solutions after condensing a posynomial into a monomial. On the other hand, logarithmic and underline{d}ifference-of-two-underline{c}oncave-functions (D.C.) approximations lead us to solving a series of convex relaxation programs. With the three proposed SCA-based power optimization solutions, we show that the overall joint subchannel and power allocation algorithm converges to some local maximum of the original design problem. While a central processing unit is required to implement the AGM approximation-based solution, each BS locally computes the optimal subchannel and power allocation for its own servicing cell in the logarithmic and D.C. approximation-based solutions. Numerical examples confirm the merits of the proposed algorithm. |

URI: | http://localhost/handle/Hannan/280935 http://localhost/handle/Hannan/522334 |

ISSN: | 1536-1276 |

volume: | 13 |

issue: | 1 |

Appears in Collections: | 2014 |

Files in This Item:

File | Size | Format | |
---|---|---|---|

6678362.pdf | 859.78 kB | Adobe PDF |