logo
    Dynamic Fractional Frequency Reuse (FFR) scheme for two-tier network in LTE
    5
    Citation
    16
    Reference
    10
    Related Paper
    Citation Trend
    Abstract:
    Femtocell networks are a promising solution to enhance the capacity of the LTE networks, especially for the indoor environments. However, unplanned deployment of the femtocells causes the co-tier interference and cross-tier interference. The interference limits the advantages of deploying the femtocell networks. The Fractional Frequency Reuse (FFR) concept is introduced to mitigate the effect of the interference on the system. In this work, Dynamic scheme is proposed to partition the spectrum efficiently. The objective of the proposed scheme is to increase the capacity of the femtocells, which enhances the performance of the system and benefits of fmetocells. The proposed scheme assign less resources for macrocell's part, which has more deployed femtocells in order to reuse as much as possible of the available resources. An experiment is conducted in order to evaluate the proposed scheme. The results indicates that the proposed scheme can increase the capacity of the system.
    Keywords:
    Macrocell
    Femtocell
    This paper proposes a coverage-oriented femtocell network deployment scheme, in which the femtocell base stations (BSs) can decide whether to be active or inactive depending on their distances from the macrocell BSs. Specifically, as the areas close to the macrocell BSs already have satisfactory cellular coverage, the femtocell BSs located inside such areas are kept to be inactive. Thus, all the active femtocells are located in the poor macrocell coverage areas. Based on a stochastic geometric framework, the coverage probability can be analyzed with tractable results. Surprisingly, the results show that the proposed scheme, although with a lower defacto femtocell density, can achieve better coverage performance than that keeping all femtocells in the entire network to be active. The analytical results further identify the achievable optimal performance of the new scheme, which provides mobile operators a guideline for femtocell deployment and operation.
    Femtocell
    Macrocell
    Stochastic geometry
    Coverage probability
    Femto-
    Citations (17)
    Deployment of femtocells (Home eNode Bs) along with existing macrocells has been drawn considerable attention of mobile industry because of its potential to reduce Operational Expenditure to the operators by offloading traffic from macrocell to femtocells. In this paper, we evaluate the energy efficiency of co-channel deployed macrocell-femtocell networks considering centralized control for HeNBs. We also show the impact of macro-cell power configuration on the energy efficiency. The results show that significant amount of improvement in energy efficiency can be achieved by centrally coordinating macrocell and femtocell networks, according to varying traffic load condition without affecting the Quality of Service requirements of macrocell and femtocell users.
    Femtocell
    Macrocell
    Femtocell network is a new technology that uses the advantage of an Internet backbone to enhance the cellular coverage in residential or small business areas. However, due to the expected random deployment of the femtocell access point (FAPs), there is a strong probability of interference among the femtocell nodes and between the femtocells and the macrocell nodes. In this chapter, an interference enhancement for multi-femtocells is developed and designed for two tiers macro-femtocell networks. An adaptive power control is calculated based on selecting the minimum interference channel with the optimized channel gain. In the simulation a number of the FAPs, the distance between the macrocell and the femtocell and the path loss between the macrocell node and the FAPs are used as design parameters. The results show a performance enhancement in the interference degradation ratio
    Femtocell
    Macrocell
    Femto-
    Citations (0)
    In this paper, we study the reverse link (RL) capacity of a co-channel macrocell-femtocell network, where the macrocell and femtocell networks share the same carrier. The analysis is done based on an outage probability criterion, and we use this analysis further to compare the capacities of different practical multi-carrier macrocell-femtocell deployment strategies.
    Macrocell
    Femtocell
    Femto-
    Citations (11)
    Femtocell base station (BS) is a low-power, low-price BS based on cellular communication technology. It is expected to become a cost-effective solution for improving the communication performance of indoor users, whose traffic demands are large in general. There are mainly three access strategies for femtocell, i.e., closed access, open access and hybrid access strategies. While it has been generally known that open/hybrid access femtocells contribute more to enhancing the system-wide performance than closed access femtocells, the operating parameters of both macro and femtocells should be carefully chosen according to the mobile operator's policy, consumer's requirements, and so on. We propose long-term parameter optimization schemes, which maximize the average throughput of macrocell users while guaranteeing some degree of benefits to femtocell owners. To achieve this goal, we jointly optimize the ratio of dedicated resources for femtocells as well as the femtocell service area in open access femtocell networks through the numerical analysis. It is proved that the optimal parameter selection of open access femtocell is a convex optimization problem in typical environments. Then, we extend our algorithm to hybrid access femtocells where some intra-femtocell resources are dedicated only for femtocell owners while remaining resources are shared with foreign macrocell users. Our evaluation results show that the proposed parameter optimization schemes significantly enhance the performance of macrocell users thanks to the large offloading gain. The benefits provided to femtocell users are also adaptively maintained according to the femtocell users' requirements. The results in this paper provide insights about the situations where femtocell deployment on dedicated channels is preferred to the co-channel deployment.
    Femtocell
    Macrocell
    Citations (13)
    This paper proposes a self-optimized coverage coordination scheme for two-tier femtocell networks, in which a femtocell base station adjusts the transmit power based on the statistics of the signal and the interference power that is measured at a femtocell downlink. Furthermore, an analytic expression is derived for the coverage leakage probability that a femtocell coverage area leaks into an outdoor macrocell. The coverage analysis is verified by simulation, which shows that the proposed scheme provides sufficient indoor femtocell coverage and that the femtocell coverage does not leak into an outdoor macrocell.
    Femtocell
    Macrocell
    Transmitter power output
    Access configuration of femtocell networks carries critical importance due to the resulting interference scenarios. Especially in closed-access femtocell networks, there might be significant interference between the femtocell and the macrocell users. In this paper, we evaluate the capacity of closed access femtocell networks employing various dynamic spectrum reuse techniques. When there is a macrocell user in the vicinity of a femtocell, the femtocell may dynamically decide not to reuse the spectrum of the macrocell user to avoid interference. We discuss and evaluate the following three decision criteria for this purpose: maximum sum capacity, minimum macrocell loss, and minimum effective interference. Computer simulations in realistic settings are provided to demonstrate possible gains with the proposed methods.
    Macrocell
    Femtocell
    Frequency allocation
    Citations (16)
    Femtocells (HeNB) are deployed within macrocell coverage area to increase performance of indoor user. In order to cover, all indoor users, HeNBs make a network, known as femtocell network. Since, HeNBs use same spectrum, they are causing interference on both MeNB users (MUE) and among HeNB users (HUE). The performance of the femtocell network depends on the SINR of HUEs of respective HeNBs, which eventually depends on the interference produced on it. In order to improve the performance, we need to minimize the interferences among themselves. In this paper, we first study the SINR performance of HUEs in the macrocell environment. We also analyze the outage probability in femtocell network. Finally, we consider the power consumption issue of femtocell network.
    Macrocell
    Femtocell
    Femto-
    The femtocell network is a new technology that uses the advantage of an Internet backbone to enhance the cellular coverage in residential or small business areas. However, due to the expected random deployment of the Femtocell Access Point (FAP), there is a strong probability of interference among the femtocell nodes and between the femtocells and the macrocell nodes. In this chapter, an interference enhancement for OFDMA systems is developed and designed for two tiered macro-femtocell networks. An adaptive power control is calculated based on selecting the minimum interference channel with the optimized channel gain. In the simulation a number of the FAPs, the distance between the macrocell and the femtocell, and the path loss between the macrocell node and the FAPs are used as design parameters. By using optimized power control performance enhancement the interference degradation ratio can be observed.
    Macrocell
    Femtocell
    Transmitter power output