Md. Selim Al Mamun

Quantum Cost Optimization for Reversible Sequential Circuit

Reversible sequential circuits are going to be the significant memory blocks for the forthcoming computing devices for their ultra low power consumption. Therefore design of various types of latches has been considered a major objective for the researchers quite a long time. In this paper we proposed efficient design of reversible sequential circuits that are optimized in terms of quantum cost, delay and garbage outputs. For this we proposed a new 3*3 reversible gate called SAM gate and we then design efficient sequential circuits using SAM gate along with some of the basic reversible logic gates.

Design of Reversible Counter

This article presents a research work on the design and synthesis of sequential circuits and flip-flops that are available in digital arena; and describes a new synthesis design of reversible counter that is optimized in terms of quantum cost, delay and garbage outputs compared to the existing designs. We proposed a new model of reversible T flip-flop in designing reversible counter. Keywords—Flip-flop; Counter; Garbage Output; Reversible Logic; Quantum Cost

Efficient Design of Reversible Sequential Circuit

Reversible logic has come to the forefront of theoretical and applied research today. Although many researchers are investigating techniques to synthesize reversible combinational logic, there is little work in the area of sequential reversible logic. Latches and flip-flops are the most significant memory elements for the forthcoming sequential memory elements. In this paper, we proposed two new reversible logic gates MG-1 and MG-2. We then proposed new design techniques for latches and flip-flops with the help of the new proposed gates. The proposed designs are better than the existing ones in terms of number of gates, garbage outputs and delay.

Active Access-Point Configuration Algorithm with Dynamic Mobile Router Placement for Elastic WLAN System

Recently, a variety of wireless access points (APs) have been deployed by many organizations to meet different traffic demands. Previously, we proposed an active AP configuration algorithm that activates or deactivates heterogeneous AP devices depending on the traffic demand and network topology, in order to realize the elastic Wireless Local-Area Network (WLAN) system. Unfortunately, in this algorithm, the locations of the mobile routers have been fixed as the algorithm input, although they can be placed flexibly as portable APs using cellular networks. In this paper, we consider the elastic WLAN system with mobile routers which can be placed flexibly. The dynamic mobile router placement is proposed for the active AP configuration algorithm to meet stringent traffic requirements. Specifically, if some hosts fail to meet the throughput requirements, the locations of additional mobile routers are dynamically determined by applying the K-means algorithm to maximize the number of those failed hosts in its coverage. The effectiveness of this location determination is demonstrated by numerical examples with three network scenarios.

A Minimax Approach for Access-Point Setup Optimization Using Throughput Measurements in IEEE802.11n Wireless Networks

Recently, an IEEE802.11n access point (AP) has become common in the wireless local-area network (WLAN) due to the high-speed data transmission using the multiple input multiple output (MIMO) technology. However, the signal propagation from the 802.11n AP may not be uniform in the circumferential direction because of multiple antennas in MIMO, in addition to the height direction. As a result, the data transmission speed between the AP and a host can be significantly affected by their relative setup conditions. In this paper, we propose a minimax approach for optimizing the 802.11n AP setup condition in terms of the height and the angles in an indoor environment using throughput measurements. First, we detect a bottleneck host that receives the weakest signal from the AP in the field using the throughput estimation model. Then, we optimize the AP setup by changing the height and directions while measuring throughputs. For evaluations, we confirm the accuracy of the model using measurement results and the throughput improvements at most hosts including the bottleneck one in the field by our approach.

Cross-layer selective routing for cost and delay minimization in IEEE 802.11ac wireless mesh network

A Wireless Internet-access Mesh NETwork (WIMNET) provides scalable and reliable internet access through the deployment of multiple access points (APs) and gateways (GWs). In this work, we propose a selective routing algorithm aiming at a hierarchical minimization of the operational cost and the maximal end-to-end delay. In particular, by deploying redundant APs/GWs in the network field, the WIMNET becomes robust to the link or AP/GW failure. However, these redundant APs/GWs increase the operational cost like the power consumption. By using Dijkstra algorithm and 2-opt algorithm, the proposed algorithm iteratively deactivates the deployed APs/GWs and performs the routing that reduces the maximal end-to-end delay based on the APs/GWs remaining active. The generated route meets the real-world constraints like fairness criterion. We further propose a cross-layer design to enhance the routing performance by exploiting the MAC-layer frame aggregation technique. The selective routing algorithm is then implemented in the WIMNET simulator proposed by our group. The numerical experiments demonstrate that in both indoor and open space environments, the proposed selective routing greatly reduces the operational cost, i.e., up to

Pseudo random binary sequence: A new approach over finite field and its properties

80\%

On the autocorrelation and cross-correlation of ternary möbius sequence over finite field

80% APs/GWs can be deactivated.