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This paper investigates the effect of the path loss exponent $a$ on the Ergodic Capacity (EC) of the cellular systems. Previous studies examined this effect with certain values of $a$ with the association of single and multiple Remote Radio Heads (RRHs). In this work, a closed-form expression for the ergodic capacity is derived for the association with two RRHs using arbitrary values of path loss exponent and an ergodic capacity analysis for Nearest_RRH (NR_RRH) is also considered. Results reveal the relation between the channel capacity and $a$ at different levels of transmitted power for the uplink using multiple antennas at each RRH.

The syntheses, structure-activity relationships (SARs), and biological activities of tetrahydroquinoline-based tricyclic amines as 5-HT2C receptor agonists are reported. An early lead containing a highly unique 6,6,7-ring system was optimized for both in vitro potency and selectivity at the related 5-HT2B receptor. Orally bioactive, potent, and selective 6,6,6-tricyclic 5-HT2C agonists were identified.

Radio spectrum for mobile operators is an expensive resource that should be wisely provisioned to meet users’ demands. In long term evolution-advanced, the number of physical resource blocks (PRBs) are used to gauge the users’ needs. Accordingly, there is a time in the network when it is beneficial to gain the advantages of consuming the unused PRBs in the transport block (TB) context to operate at a significantly lower power cost per PRB. The novelty of the letter is that the $3\text{rd}$ generation partnership project (3GPP) standard tables are used with multiple-input-multiple-output (MIMO) spatial multiplexing mode, to control the transport block size (TBS) index. This can be done by setting more PRBs and hence changing the modulation order that leads to reducing the transmitted power. In addition to that, MIMO layers, the prerequisite throughput, the intercell interference as well as the channel conditions of each user are considered as constraints to improve the downlink power efficiency. To describe the abovestated problem, an optimization problem is formulated as binary integer nonlinear program, which is very difficult to solve. Thus, a reformulation linearization technique based on a branch-and-bound framework is used to simplify the aforementioned BINLP.

The customer-installed femtocell is considered an efficient technique for solving the coverage and data rate problems inside buildings. In this letter, we introduce a component carrier (CC) group selection mechanism that helps the femtocells to find the optimal carrier aggregation (CA) for a long term evolution-advanced network, relies on the principle of distribution architecture. This mechanism is adopted from cellular manufacturing systems for the machine-part formation problem. By optimizing the CA selection, the proposed scheme can avoid the interference among femtocells and eNodeBs, maximize the system spectral efficiency, and enhance the coverage. A self-organization model for minimizing the variance between the CCs within the CA groups is introduced, where a novel interference threshold calculation is derived to bias the selection of the optimal group.

This work discusses a new time-of-use energy pricing structure based on grid frequency. Under the proposed pricing structure, energy cost depends on the time of frequency deviation and the period during which energy is used. This pricing mechanism is intended for use with multiple behind-the-meter home batteries as part of a frequency-controlled smart load strategy known as a battery buffered smart load. The load energy consumption from the grid and energy storage rates thus depend on the frequency deviation and hours of use, which means that the proposed pricing encourages battery-using customers to not only utilise energy arbitrage, shifting peak demand but also to contribute to demand-side primary frequency control. The second contribution of this paper is the presentation of an operation strategy for multiple buffered battery smart load units in which charge and discharge decisions are made according to off- and on-peak period information to ensure continuous provision of primary frequency control under the proposed time of frequency division pricing. A MATLAB simulation of the proposed pricing and operation modes of the BBSL was conducted with multiple battery-buffered smart load to assess feasibility.

The decode-and-forward (DF) relay based cellular network is considered an efficient technique for solving the coverage and improving system capacity of the current fourth-generation (4G) and the emerging fifth-generation (5G) mobile telecommunication technologies. In this analysis, we control the codeword's transmission parameters by achieving a good trade-off between setting more resources with changing the modulation order, hence reducing the relay's access link transmitted power. We first address the calculations of codeword's size in 3GPP specification, where an unhealthy component carrier selection mechanism is introduced for defining relay's transmission spectrum. Then, we present a novel 3GPP-compliant binary integer optimization model subject to several practical constraints, such as the requisite resources and throughput. Through system level simulations, the proposed approach is compared with the conventional relaying systems. It is shown that our approach has made several improvements to the conventional schemes.

The radio spectrum for mobile operators is a precious resource that should be wisely provisioned to meet the users' demands and enhance the network performance. Currently, the machine- type communication (MTC) technique is becoming an important part of the evolving cellular network. This paper proposes an effective approach for MTC resource allocation, where the number of resources is used to gauge the MTC devices (MTCDs) transmitted power. Conceptually, the MTCDs elaborate and exchange a lightweight data-traffic and demanding fewer resources. Therefore, in this analysis, we control the index of the transport block size by setting more radio resources, hence reducing the modulation order with respect to the MTCDs' positions and the prerequisite data rate. In addition, we introduce a novel 3GPP-compliant binary-integer optimization model for ensuring an efficient trade-off between the index of the transport block size and the required number of resources for the downlink assignment problem. A major design challenge is to deal with the required throughput, the interference from neighboring cells, as well as the current channel conditions of each MTCD as a set of constraints for operating at a significantly lower power cost per resource. A series of comprehensive simulations is conducted. It is shown that the proposed approach has made several improvements to the conventional schemes.

In this paper, we introduce a new approach to weaken the effect of inter-cell codeword interference caused by two adjacent cells, which leads to a reduction in the communication performance at the cell-edge users. The objective is to create a new transmission procedure exchanged by the proximate base stations to ensure an efficient communication in the context of multiple-input-multiple-output (MIMO) transmissions. One of the most important issues is how the cell-edge users detect and decode the outcomes observed from the individual multi-streams of multi-codewords transmitted by two neighboring base stations. To address this problem, this paper presents a novel framework based on the network assisted interference cancellation and suppression (NAICS) technique. Its application to the scenario with two adjacent base stations and cellular-edge users is guided by two schemes. First, two base stations explicitly define and exchange the transmission policy for each codeword regarding the modulation index, the number of streams, and the order of the transmitted codewords. Second, a new taxonomy scheme is proposed, where the Bayesian decision classifier theory is used for the cell-edge users to extract the judgment rules from the exchanged transmission policy and enable symbols estimation and recognition in terms of posterior probability statements, hence offering a decision for each codeword. We introduce an integer optimization model subject to several practical constraints, such as the channel conditions of the users, the number of subcarriers, and the required throughput. The numerical tests demonstrate how to satisfy these requirements while validating the benefits over conventional approaches.

The syntheses, structure-activity relationships (SARs), and biological activities of tetrahydroquinoline-based tricyclic amines as 5-HT

In this paper, we present a new approach that seeks the efficient power allocation in LTE-A based on ordering methodology of active UEs. The feature of non-contiguous CA is implemented with the SISO mode and the infinite buffer traffic type. The proposed approach consists of two aspects: (1) finding the optimal power allocation for each UE by selecting the proper subcarriers, with respect to the required throughput, the current channel condition for each UE, and the interference from neighboring eNodBs, (2) achieving the fairness among multiple UEs with respect to power distribution. We formulate an optimization model to achieve the proposed approach. A set of comprehensive simulations is conducted. It is shown that the new approach has made several improvements on the conventional schemes.

In this paper, we present a new approach that seeks reducing the downlink TBS-index by the LTE-A eNodeB. Our objective is to minimize the total transmitted power based on getting the benefit from available but unused PRBs, while considering the QoS for the UEs and mitigating the interference from adjecent eNodeBs. Most previous studies have not assigned the residual PRBs in the eNodeB to change the MCS order in the context of TB. Also, they have not considered the TBS-index as a constraint. In this paper, we formulate a new downlink assignment problem that takes the TBS-index into account, where the PRBs are selected for each TB based on the total available but unused PRPs and the CQI of each UE. Controlling the TBS-index while increasing the number of PRBs will have an effect on the MCS order, hence reducing the transmitted power with respect to the positions of UEs. The TB corresponding to using one MCS and one CC is implemented to enhance the throughput of a generic system with the SISO mode and the infinite buffer traffic type. The proposed approach consists of two aspects: (1) exploiting the residual PRBs among multiple UEs to reduce the TBS-index, (2) finding the optimal power allocation for each UE regarding the optimal MCS, relating to the required throughput, as well as the current channel state information of each UE. The proposed approach is implemented with a greedy algorithm. A set of comprehensive simulations is conducted. It is shown that our approach has made several improvements to the conventional approaches.