Birefringence examination in a practical fiber-current-sensing system

The output of a fiber-current sensor with a nonideal input (either misaligned linear or elliptical polarization) and moderate output misalignment in the setup (the fiber end versus the Wollaston prism) has been considered. Based on this, a novel method that uses a statistical approach, including a set of scanning elliptical polarization inputs and the corresponding curve-fitting outputs for a given current, is used to determine the birefringence of the fiber-current-sensing system. The experimentally measured bend-induced birefringence agrees with the estimated value of the bend birefringence.     

Design of two-channel perfect-reconstruction linear-phase finite-duration impulse response filter banks for subband image coding by the genetic algorithm approach

In this paper, a powerful approach is proposed for the design of two-dimensional two-channel perfect-reconstruction finite-duration impulse response filter banks employing diamond-shaped linear-phase filters. When one of the analysis filter pair is properly designed, the condition of perfect reconstruction is formulated in a spatial-domain constraint equation for designing the other. The method is based on minimizing the integrated square error for the frequency response over the pass band and stop band while imposing the spatial-domain constraint. One numerical design example is given to demonstrate the perfect reconstruction for the proposed system.     

Channel Management for Multi-Service Traffic in Cellular Wireless Networks

Channel management aims to provide quality of service guarantees for mobile users while efficiently utilize limited radio spectrum. With the increasing demand for diverse services in wireless networks, channel management for multi-service traffic in wireless networks is important. To provide diverse broadband services in limited radio spectrum, previous literature has presented adaptive services which provide mobile users with good quality of services. This study considers channel management for multi-service traffic in wireless networks with adaptive services. A channel management scheme, namely, restricted sharing, is devised to provide multi-class traffic with quality of service guarantees while increase channel utilization as much as possible. An analysis is used to study the performance of the restricted sharing scheme. Three classes are considered in numerical results. Numerical results show that the restricted sharing scheme guarantees quality of service and achieves high channel utilization.     

Diagnosis by Image Recovery: Finding Mixed Multiple Timing Faults in a Scan Chain

In this brief, we present a robust new paradigm for diagnosing a scan chain with multiple faults that could have different fault types. As compared to previous methods, the major advantage of ours is the ability to not only target mixed multiple types of timing faults in the same scan chain but also tolerate non-ideal conditions, e.g., when these faults only manifest themselves intermittently. Unlike the previous matching-based algorithms, we formulate the diagnosis problem as an image recovery process featuring a dynamic windowing technique and a running sequence handling technique. Experimental results on a number of real designs show that this paradigm can successfully deal with some situations beyond existing methods.     

Theoretical Analysis of Novel Multi-Order LC Oscillators

A conventional differential pair LC oscillator is capable of generating only a single fundamental oscillation frequency. This brief presents the theoretical study of a novel oscillator that incorporates higher order LC filters to produce multiple oscillation frequencies that may be several octaves apart. These multiple oscillation frequencies are obtained from a single oscillator, thereby reducing the area of the circuit when being used for multistandard wireless applications. Moreover, a multi-order oscillator does not suffer from large parasitic capacitances from switches, which is a common drawback in switched-inductor tuned oscillators. A detailed analysis is carried out, and useful design insights are provided     

A new convertible authenticated encryption scheme with message linkages

In this article, we present an authenticated encryption scheme with message linkages used to deliver a large message. To protect the receiver’s benefit, the receiver can easily convert the signature into an ordinary one that can be verified by anyone. Several feasible attacks will be discussed, and the security analysis will prove that none of them can successfully break the proposed scheme.     

Vendor selection by integrated fuzzy MCDM techniques with independent and interdependent relationships

Vendor selection is an evaluation process that is based on many criteria that uses inaccurate or uncertain data. But while the criteria are often numerous and the relationships between higher-level criteria and lower-level sub-criteria are complex, most conventional decision models cannot help us clarify the interrelationships among the sub-criteria. Our proposed integrated fuzzy multiple criteria decision making (MCDM) method addresses this issue within the context of the vendor selection problem. First, we use triangular fuzzy numbers to express the subjective preferences of evaluators. Second, we use interpretive structural modeling (ISM) to map out the relationships among the sub-criteria. Third, we use the fuzzy analytical hierarchy process (AHP) method to compute the relative weights for each criterion, and we use non-additive fuzzy integral to obtain the fuzzy synthetic performance of each common criterion. Fourth, the best vendor is determined according to the overall aggregating score of each vendor using the fuzzy weights with fuzzy synthetic utilities. Fifth, we use an empirical example to show that our proposed method is preferred to the traditional method, especially when the sub-criteria are interdependent. Finally, our results provide valuable suggestions to vendors on how to improve each sub-criterion so that they can bridge the gap between actual and aspired performance values in the future.     

Full-duplex radio-on-fiber transport systems based on main and multiple side modes injection-locked DFB laser diode

A full duplex radio-on-fiber (ROF) transport system based on main and multiple side modes injection-locked distributed feedback laser diode (DFB LD) is proposed and experimentally investigated. DFB LD is successfully injection-locked not only in the main mode but also in other side modes. A data signal of 70 Mbps/10 GHz (WiMAX) signal is transmitted over long-haul single-mode fiber (SMF) transmission. Good bit error rate (BER) performances were achieved for both down-link and up-link transmissions in our proposed full-duplex ROF transport systems.     

A self-stabilizing algorithm for the maximum planarization problem in complete bipartite networks

The maximum planarization problem is to find a spanning planar subgraph having the largest number of edges for a given graph. In this paper, we propose a self-stabilizing algorithm to solve this problem for complete bipartite networks. The proposed algorithm finds the maximum planar subgraph of 2n−4 edges in O(n) rounds, where n is the number of nodes.