16326025
Research on Positioning Technology of Xinjiang Mobile GIS
In this paper, the characteristics of Xinjiang mobile communication network are analyzed, the results show that for a reliable mobile communication network, BS (base station) and base station control BSC (base station controller) monitoring system, cable and fiber optic cable monitoring system and mobile communications troubleshooting and dispatching system should be built. Combined with GIS, GPS, GSM and geographic database technology, positioning technology for different targets and detection on fault point are studied, the results indicate that precise positioning of static target can accurately locate the failure telecom equipment in the electronic map and provide data source for the realization of real-time monitoring and management system for telecom equipment based on GIS & wireless sensor network technology. GSM-based wireless messaging communications and real-time fast positioning of dynamic target is the key to the emergency repair vehicles monitoring and dispatch system. The proposed fault determination and fault point location method can provide fast accurately fault devices location with detailed geography information and prompt the efficiency of fault management and improve the reliability of telecom network services. The above research results are important basis on the design and implementation of the system.
43405539
An Improved Method of Traffic Forecasting Based on Tariff-SASVR
Traffic forecasting is critical for mobile operators to grasp market trends and control network capacity. Therefore, an improved method of forecasting for mobile traffic is presented in this paper. The traffic is divided into the general trend part and seasonal part to forecast them respectively. The general trend is predicted by fitting the curve of general trend on tariff level; and the remaining seasonal part is predicted by simulated annealing-support vector regression machine (SASVR) which uses simulated annealing (SA) to select the super-parameters of SVR. The experimental results show that not only this method improves the prediction accuracy but it provides mobile operators with a visual expression of the relationship between traffic and the tariff level.
5494803
Wireless Network Dynamic Topology Routing Protocol Based on Aggregation Tree Model
As the scale of the network increases, especially wireless and mobile networks comes into fashion, the problem of network dynamic topology management turns into a focus topic in the network world. When network information changes, frequent route computing and network state updates can cause computing and traffic overhead, respectively. Therefore, minimum of influence to network structure has been identified as one of the key issues in designing dynamic network routing protocols. A novel protocol, which is based on Aggregation Tree Routing Model (ATRM) as well as an effective ball-and-string algorithm, is introduced in this paper which aims to minimize the alteration of network topology and to speed up the minimum cost route computation. This routing protocol is applicable to all kinds of networks, including Internet, ad hoc and wireless sensor networks. The simulations show that our protocol not only results in significantly lower overhead, but also gives high levels of dynamic network topology management performance while keeping practical.
3369144
Adaptive Multi-Channel MAC Protocol for Dense VANET with Directional Antennas
Directional antennas can increase the spatial reuse of the wireless channels and reach a higher antenna gain. This paper presents the design, implementation and simulation results of a multi-channel medium access control protocols for high density vehicular ad hoc networks using directional antennas with local beam tables. Simulation shows that our protocol has a higher throughput than the existing multi-channel protocols.
6929789
WSN02-2: Adaptive Network Resource Management in IEEE 802.11 Wireless Random Access MAC
Effective and efficient management of wireless network resources is attracting more and more research attention, due to the rapid growing deployment of wireless mesh and ad hoc networks and to the increasing demand for Quality of Service (QoS) support in these networks. This paper proposes an adaptive network resource management scheme in the popular IEEE 802.11 random access MAC by adaptively adjusting the minimum contention window sizes of traffic flows. First, a novel generalized processor sharing (GPS) model is presented for the IEEE 802.11 random access MAC revealing the relationship between the minimum contention window size of a traffic flow and the amount of network resource this flow can receive. Using this GPS MAC model, a feedback control system model for the proposed adaptive network resource management system is developed, by directly extending our previous work in wireline GPS networks. Based on the feedback control system model, adaptive P and adaptive PI controllers are designed, and their performances are studied in simulations. Simulation results show that by using the designed controllers, the proposed adaptive network resource management approach is able to provide guaranteed distinct QoS support to traffic flows.
8390786
A modular NFA architecture for regular expression matching
We propose a non-deterministic finite automata (NFA) based architecture for regexp scanners on FPGA, called CES: the Character Class with Constraint Repetition (CCR) based regExp Scanner. CES is designed to realize a new MIN-MAX counting algorithm, which can solve both the character class ambiguity problem and the overlapped matching problem. CES also supports non-regular Perl grammars such as zero-width pattern and back-reference. We propose a CCR-syntax tree and its parsing scheme to map a Perl or POSIX regexp rule to a CES topology. The interconnection patterns, and operational parameters of CCR modules (CCRM), which are the building blocks of CES, can be easily configured by regular memory writes when regexp rules change, without re-synthesis of low-level logic.
 For implementation, character classes of CCRs are stored in Block RAMs. The MIN-MAX algorithm uses two counters MIN and MAX to resolve the character class ambiguity problem. Two checkpoint counters are employed to implement overlapped matching detection. CES topologies optimized for different types of rules can run in different Partial Reconfigurable Regions (PRR), and can be swapped on the fly by a PRR controller. We developed a tool chain to automate the CES implementation to a Virtex 5 LX110T device. This device can host up to 3000 CCRMs, and run at an estimated throughput of 1.996 Gbps in simulation, and 863 Mbps between a PC and the Virtex 5 board in real tests. The Snort and SpamAssassin rule sets can be parsed and mapped in milliseconds. Once a base CES architecture is synthesized, the physical reconfiguration of a CES on the Virtex 5 LX110T chip can be done in less than a second.
11024065
An algorithm for optimal comma free codes with isomorphism rejection
A general algorithm for finding optimal comma-free codes and deriving upper bounds on the minimum redundancy of comma-free codes that implements the idea of isomorphism rejection is presented, together with tables with bounds on the minimum redundancy computed by using this algorithm.