No abstract

A novel attempt is made by creating the stacked sequences of two different frequencies that provide the intended performance by suppressing the harmonic interferences between them. This electromagnetic interference (EMI) is suppressed in stacked system by incorporating the circular complementary split ring resonator (CCSRR) in the ground plane. The proposed system consists of two patch antennas operating at 2 GHz and 4 GHz with CCSRR for harmonic suppression. The lower rung antenna operates at 2 GHz fed by inset feeding and the top rung antenna operates at 4 GHz fed by coaxial feeding such that both radiators share a common ground plane. The lower rung antenna (2 GHz) has its first harmonic at 4.02 GHz with the magnitude of 11.5 dB that ensue an EMI to the other antenna operating at 4 GHz (top rung antenna in the stacked system). By introducing the CCSRR beneath the microstrip feed line (2 GHz), the EMI is suppressed. The simulated and measured results are in good agreement. Moreover, the proposed antenna finds its application in radar target scanning, narrow band channel selector, and low power narrow band wireless receivers.

This article presents a design of highpass filter (HPF) for millimeter-wave (mm-wave) applications using a square complementary split-ring resonator (SCSRR). A miniaturized size HPF filter is obtained by overlapping the Right-Hand (RH) and Left-Hand material. The arrangement of inter-digital parallel coupled capacitor and SCSRR offers low insertion loss, high selectivity with a sharp roll-off factor over a wide bandwidth of 15.9 GHz (from 34.1 to 50 GHz). Generally, SCSRR offers narrow passband/stopband however this prototype has a passband over a wide range of frequency. The proposed HPF has an appreciable agreement between simulated and fabricated results. Further, the filter is realized in the equivalent circuit model and their electrical elements functions are also discussed. This prototype has a cut-off frequency (fc) of 34.1 GHz with a maximum passband insertion loss of 1.45 dB. The fabricated area of the filter is 0.16λg × 0.09λg × λg and where λg is the guided wavelength at cutoff frequency fc.

This paper focuses on the trade-off between flexibility and efficiency in specialized computing. We observe that specialized units achieve most of their efficiency gains by tuning data storage and compute structures and their connectivity to the data-flow and data-locality patterns in the kernels. Hence, by identifying key data-flow patterns used in a domain, we can create efficient engines that can be programmed and reused across a wide range of applications. We present an example, the Convolution Engine (CE), specialized for the convolution-like data-flow that is common in computational photography, image processing, and video processing applications. CE achieves energy efficiency by capturing data reuse patterns, eliminating data transfer overheads, and enabling a large number of operations per memory access. We quantify the tradeoffs in efficiency and flexibility and demonstrate that CE is within a factor of 2-3x of the energy and area efficiency of custom units optimized for a single kernel. CE improves energy and area efficiency by 8-15x over a SIMD engine for most applications.