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Abstract-We applied a useful uncertainty model, ignored in most metamaterials retrieval studies, to monitor the accuracy of retrieved electromagnetic properties of bianisotropic metamaterial (MM) slabs composed of split-ring resonators and cut wires. Two different MM slab structures are considered to make the analysis complete. As uncertainty-making factors, we took into consideration of uncertainties in scattering (S-) parameters of bianisotropic MM slabs as well as the length of these slabs. The applied uncertainty model is based upon considering the effect of minute change (differential) in uncertainty factors on the retrieved electromagnetic properties of bianisotropic MM slabs. The significant results concluded from the analysis are: 1) any abrupt changes in the phase of S-parameters of bianisotropic MM slabs remarkably influence the retrieved electromagnetic properties; 2) any small-scale loss (i.e., the loss of the substrate) in the bianisotropic MM slabs improves the accuracy of the retrieved electromagnetic properties of these slabs; and 3) precise knowledge of bianisotropic MM slab lengths are required for correct analysis of exotic properties of these slabs. The presented uncertainty analysis can be utilized as a metric tool for evaluating various retrieval methods of MM slabs in the literature.

This study presents a modeling of a new reconfigurable patch antenna with equivalent lumped circuit. Instead of intuitive approaches, including structural changes used in the literature, the proposed reconfigurable antenna design is based on minimum tuning effort using only capacitance adjustments. The proposed design resolves impedance mismatch problem, which occurs due to the nature of using several frequencies by only capacitance adjustments rather than physical structure adjustments. Reconfigurable patch antenna for 2.45 GHz (Wi‐Fi), 3.6 GHz (Wi‐max and 5G), 5.4 GHz (WLAN and 5G) was considered for novel design strategy. A complete equivalent circuit model is configured and validated through AWR software. Full wave analysis of the proposed antenna is performed using CST software. A prototype of the proposed antenna is also fabricated on a FR4 substrate with the dimensions of 48.19 x 38.36 x 1.53 mm3 and measured to validate the full wave analysis and circuit theory solution results. It is shown that the equivalent circuit model, full wave analysis, and measurement results are in good agreement.

In this paper, the problems of redundancy allocation for providing effective error-resilience and service class distribution for enhanced quality of service (QoS) in real-time MPEG-2 video transport are addressed. A real-time low-complexity content-based adaptive error-resilient approach is proposed for the transport of MPEG-2 video streams, encapsulated using real-time transport protocol (RTP) and delivered over heterogeneous networks. An algorithm is derived using spatial and temporal properties of MPEG-2 video for assigning weights to each packet based on the estimated perceptual error. These weights, which indicate the relative importance of RTP packets, together with the communication channel characteristics are used to determine the allocation of resources for providing improved error-resilience and for assigning data packets to various classes of service in order to enhance the quality of transmission. Parameters extracted from the RTP header are used to determine the weights, so that the proposed algorithm can be implemented in real-time. This algorithm is used for adaptively allocating redundant forward error correction packets as well as for marking and forwarding of RTP packets in differentiated services (DiffServ). Simulation results are presented to show the significant improvement in performance based on our proposed approach to video transport.