Power and Radio Resource Management in Femtocell Networks for Interference Mitigation

The growth of mobile traffic volume has been exploded because of the rapid improvement of mobile devices and their applications. Heterogeneous networks (HetNets) can be an attractive solution in order to adopt the exponential growth of wireless data. Femtocell networks are accommodated within the concept of HetNets. The implementation of femtocell networks has been considered as an innovative approach that can improve the network’s capacity. However, dense implementation and installation of femtocells would introduce interference, which reduces the network’s performance. Interference occurs when two adjacent femtocells are operated with the same radio resources. In this work, a scheme, which comprises two stages, is proposed. The first step is to distribute radio resources among femtocells, where each femtocell can identify the source of the interference. A constructed table is generated in order to measure the level of interference for each femtocell. Accordingly, the level of interference for each sub-channel can be recognized by all femtocells. The second stage includes a mechanism that helps femtocell base stations adjust their transmission power autonomously to alleviate the interference. It enforces a cost function, which should be realized by each femtocell. The cost function is calculated based on the production of undesirable interference impact, which is introduced by each femtocell. Hence, the transmission power is adjusted autonomously, where undesirable interference can be monitored and alleviated. The proposed scheme is evaluated through a MATLAB simulation and compared with other approaches. The simulation results show an improvement in the network’s capacity. Furthermore, the unfavorable impact of the interference can be managed and alleviated.

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Secondary Network Throughput Analysis Applying SFR in OFDMA-CR Networks

10.36227/techrxiv.13710112 ◽

2021 ◽

Author(s):

Joydev Ghosh

Keyword(s):

Power Level ◽

Access Point ◽

Frequency Reuse ◽

Network Throughput ◽

Base Stations ◽

Frame Structure ◽

Control Factor ◽

Wireless Data ◽

Femtocell Networks ◽

Secondary Network

<div>In OFDMA femtocell networks, the licensed spectrum of the macro users (MUs) are available to the femto users (FUs), on the condition that they do not spark off notable interference to the MUs. We contemplate wireless data for femto user (FU) / secondary user (SU) in cognitive radio (CR) networks where the frame structure split up into sensing and data transmission slots. Moreover, we consider soft frequency reuse (SFR) technique to improve secondary network throughput by increasing the macrocell edge user power control factor. SFR applies a frequency reuse factor (FRF) of 1 to the terminal located at the cell centre for that all base stations (BSs) share the total spectrum. But for the transmission on each sub-carrier the BSs are confined to a certain power level. However, more than 1 FRF uses for the terminals near to the macrocell edge area. In this context, we conceptualize the cognitive femtocell in the uplink in which the femtocell access point (FAP) initially perceive by sensing to find out the availability of MU after that FAP revamps its action correspondingly. Appropriately, when the MU is sensed to be non-existent, the FU transmits at maximum power. In other respect, the FAP make the best use of the transmit power of the FU to optimize the secondary network throughput concern to outage limitation of the MU. Finally, effectiveness of the scheme is verified by the extensive matlab simulation.</div>

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Uplink Resource Allocation for Interference Mitigation in Two-Tier Femtocell Networks

Mobile Information Systems ◽

10.1155/2018/9093139 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Sung-Yeop Pyun ◽

Woongsup Lee ◽

Ohyun Jo

Keyword(s):

Resource Allocation ◽

Interference Mitigation ◽

Mobile Station ◽

Base Stations ◽

System Level ◽

Optimization Scheme ◽

Femtocell Networks ◽

User Capacity ◽

Resource Allocation Schemes ◽

Capacity And Coverage

Two-tier femtocell networks, in which a large number of femto base stations (BSs) are deployed within a region overlapping with a macrocell, can provide an economical means of increasing user capacity and coverage. Given that femto BSs may be deployed with no cell planning, cross-tier interference generated from a number of macrocells and femtocells can cause severe problems. In particular, a macro mobile station (MS) that transmits uplink data may generate severe interference with adjacent femtocells, which causes performance degradation. In order to solve these problems, two novel resource allocation schemes, optimization and heuristic, are proposed, which efficiently reduce uplink interference in two-tier femtocell networks. Simulation results at the system level verify that both proposed schemes can improve the average capacity of the femtocells, but the heuristic scheme outperforms the optimization scheme in terms of computational complexity.

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Secondary Network Throughput Analysis Applying SFR in OFDMA-CR Networks

10.36227/techrxiv.13710112.v1 ◽

2021 ◽

Author(s):

Joydev Ghosh

Keyword(s):

Power Level ◽

Access Point ◽

Frequency Reuse ◽

Network Throughput ◽

Base Stations ◽

Frame Structure ◽

Control Factor ◽

Wireless Data ◽

Femtocell Networks ◽

Secondary Network

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Dynamic Set Planning for Coordinated Multi-Point in B4G/5G Networks

Sensors ◽

10.3390/s21051752 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1752

Author(s):

Jia-Ming Liang ◽

Ching-Kuo Hsu ◽

Jen-Jee Chen ◽

Po-Han Lin ◽

Po-Min Hsu ◽

...

Keyword(s):

Large Scale ◽

Base Stations ◽

System Throughput ◽

Transmission Power ◽

5G Networks ◽

Radio Resource ◽

Set Size ◽

Full Study ◽

Radio Resources ◽

Save Energy

Coordinated Multi-Point (CoMP) is an important technique in B4G/5G networks. With CoMP, multiple base stations can be clustered to compose a cooperating set to improve system throughput, especially for the users in cell edges. Existed studies have discussed how to mitigate overloading scenarios and enhance system throughput with CoMP statically. However, static cooperation fixes the set size and neglects the fast-changing of B4G/5G networks. Thus, this paper provides a full study of off-peak hours and overloading scenarios. During off-peak hours, we propose to reduce BSs’ transmission power and use the free radio resource to save energy while guaranteeing users’ QoS. In addition, if large-scale activities happen with crowds gathering or in peak hours, we dynamically compose the cooperating set based on instant traffic requests to adjust base stations’ BSs’ transmission power; thus, the system will efficiently offload the traffic to the member cells which have available radio resources in the cooperating set. Experimental results show that the proposed schemes enhance system throughput, radio resource utilization, and energy efficiency, compared to other existing schemes.

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Interference mitigation in point to point wireless sensor networks using LSP protocol and time division multiplexing approach

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189028 ◽

2020 ◽

Vol 39 (4) ◽

pp. 5449-5458

Author(s):

A. Arokiaraj Jovith ◽

S.V. Kasmir Raja ◽

A. Razia Sulthana

Keyword(s):

Energy Consumption ◽

Large Scale ◽

Control Parameter ◽

Interference Mitigation ◽

Wireless Sensor ◽

Point To Point ◽

A Minor ◽

Two Stages ◽

Time Division ◽

And Control

Interference in Wireless Sensor Network (WSN) predominantly affects the performance of the WSN. Energy consumption in WSN is one of the greatest concerns in the current generation. This work presents an approach for interference measurement and interference mitigation in point to point network. The nodes are distributed in the network and interference is measured by grouping the nodes in the region of a specific diameter. Hence this approach is scalable and isextended to large scale WSN. Interference is measured in two stages. In the first stage, interference is overcome by allocating time slots to the node stations in Time Division Multiple Access (TDMA) fashion. The node area is split into larger regions and smaller regions. The time slots are allocated to smaller regions in TDMA fashion. A TDMA based time slot allocation algorithm is proposed in this paper to enable reuse of timeslots with minimal interference between smaller regions. In the second stage, the network density and control parameter is introduced to reduce interference in a minor level within smaller node regions. The algorithm issimulated and the system is tested with varying control parameter. The node-level interference and the energy dissipation at nodes are captured by varying the node density of the network. The results indicate that the proposed approach measures the interference and mitigates with minimal energy consumption at nodes and with less overhead transmission.

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