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Video multicast exploits the wireless broadcast nature to transmit a video stream to multiple clients with a minimum bandwidth requirement. Scalable video coding (AMC) and Adaptive Modulation and Coding (AMC) are two key techniques for video multicast in broadband wireless networks. They improve the system utility value by dividing the video steam into different layers and assigning appropriate modulation...
Radio resource management in multi-user LTE networks is considered in this paper. Subject to a transmission power constraint, genetic algorithm is firstly investigated to optimize the system transmission rate. However, result shows genetic algorithm has the flaws of slow convergence rate and cannot reach to the theoretical maximum transmission rate. Aiming at this point, ant colony algorithm (ACA)...
Subcarrier allocation scheme for Orthogonal Frequency Division Multiplexing(OFDM) based multiuser system is proposed. Most previous algorithms use greedy approach as a subcarrier allocation scheme until a conflict occurs or as an initial first round allocation with improvement steps carried out in next rounds. Our algorithm uses information obtained by the forced costs of a system that incur by a...
In this paper, we study the power allocation for multiband coded OFDM systems. With limited feedback, we propose an effective power allocation method across OFDM bands to maximize the throughput and achieve the quality of service target. To facilitate the proposed method, two optimization algorithms based on greedy and dynamic programming principles are discussed. The trade-off between performance...
Scalable video coding (SVC), together with adaptive modulation and coding (AMC), can improve wireless multicast streaming video by jointly performing radio resource allocation and modulation and coding scheme (MCS) selection. However, the existing schemes in the literature allocate radio resources for different video layers separately, which leads to a waste of radio resources. In this work, we introduce...
Unequal Error Protection (UEP) is the key to future multi-layer and scalable data and video transmission. This paper presents a novel bit-loading and channel adaptation technique to realize UEP properties in the physical transport using greedy and sub-optimal bit-loading algorithms. In this case, we exploited the power minimization approach developed by the greedy algorithm to allow for an arbitrary...
This paper presents a novel technique for cross-layer adaptive modulation and coding, suited for bit interleaved turbo-coded OFDM packet transmission, and aimed at maximizing the goodput (i.e., the number of data bits delivered without error per unit of time). The optimization problem is formalized through an accurate modeling on the link performance, and a greedy iterative solution is derived. Simulation...
Future 4G cellular networks are featured with high data rate and improved coverage, which will enable realtime video multicast and broadcast services. Scalable video coding is very appropriate for wireless multicast service because it allows to choose different modulation and coding schemes (MCSs) for different video layers and can provide good video quality to users in good channel conditions while...
In this paper, a new power allocation and bit loading policy is defined for those systems working with a preselected binary channel code and specific bit error rate (BER) requirements. It consists on the maximization of the spectral efficiency with a constraint on the average mutual information per coded bit (bit MI), exploiting the relationship of the bit MI with the BER and the code rate. An irregular...
In MIMO systems, spatial multiplexing is a powerful technique for increasing channel capacity by transmitting multiple data streams in the same channel simultaneously. Moreover, additional performance can be extracted in the presence of channel state information (CSI) at the transmitter. However, channel estimation error usually exists in practical systems and leads to imperfect CSI. As a result,...
IEEE 802.16e WiMAX is a promising new technology for broadband access networks. Amongst the class of applications that can be supported is real time video services (such as IPTV, broadcast of live events etc.). These applications are bandwidth hungry and have stringent delay constraints. Thus, scalable support for such applications is a challenging problem. To address this challenge, we consider a...
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