IoT devices are increasingly threatened by malware however, conventional electromagnetic (EM) side-channel detection methods have short effective range with increased complexity. This paper proposes a novel EM-based malware detection technique that addresses these limitations by focusing on the periodic behavior of the device’s clock frequency signal. The proposed approach monitors the processor’s clock emission for anomalous periodic patterns caused by malicious code, rather than scanning a broad spectrum of harmonics. This simplification enables real-time malware monitoring without additional hardware or intrusive instrumentation. The proposed method detects the presence of malware as well as identifies the malware type by analyzing the unique periodic signature it imprints on the clock signal. Experiments on an Arduino-based IoT device demonstrate that the technique achieves 100% detection accuracy across multiple malware variants and remains effective at distances up to 8 cm from the device, significantly outperforming prior EM analysis approaches in both range and practicality. These results suggest a lightweight and non-intrusive solution for enhancing IoT device security through clock frequency analysis.

In this paper, modified E-shaped antenna is proposed. To get the wideband and flat-top radiation pattern, the double air gap structure was used in upper and lower layer for the radiator. The proposed antenna has 15% impedance band and flat-top radiation performance about 60°. This antenna can be widely used for mobile communication service requiring equal power distribution within service coverage.

This paper is concerned with the design of the K-band multi-channel module for mobile satellite communications which is a key unit of the active phased array antenna system. This module is composed of 4 individual channels having same structure for receiving part. To electrically control the antenna beam direction and pattern shaping, 5-bit MMIC phase shifters and variable attenuators including other active and passive components are included in receiving channel. Using the proposed module structure, the size and the weight of the antenna system can be considerably minimized.

Conventional polarizers usually include complicated corrugations and lossy insertions such as an iris, septa and dielectric slab, causing performance degradation and fabrication difficulties. At high frequencies, such fabrication difficulties and lossy components are limiting factors to achieving low costs and high performance. In this paper, a novel waveguide-type polarizer with an oval shaped cross-section that is inclined at a ± 45° angle for right-handed and left-handed circular polarization is presented. Due to the oval cross-section, the polarizer can be easily fabricated by mechanical processing with considerable performance. The proposed polarizer structure is fabricated using a pyramidal horn with a square aperture. From measured results, it is confirmed that the horn antenna has a gain of 9.4 dBi at 30.5 GHz with 20 dB cross-polarization level. The return loss is below -15 dB from 28 GHz to 34 GHz, and the axial ratio bandwidth is about 18% at a 3-dB level. This horn antenna will be applied to a feeder design with electrical beam scanning for a reflector-based mobile satellite antenna terminal.