This article presents a novel rectangular waveguide
bandpass filter with multiple TZs using capacitive planar
insert technology. A three-symmetrical rectangular shape
single split complementary split ring resonators (CSRRs) is
designed on a Roger RO4350 dielectric substrate and placed
in the transverse plane of a standard WR-90 rectangular
waveguide. The distance between these planar inserts is
optimized and placed at 9.654 mm to form a wideband
tri-pole bandpass filter. To introduce TZs below passband,
CSRRs with capacitive effects are introduced into the
planar insert. The numerical analysis is carried out using
CST Studio Suite. The numerical analysis shows the filter
operates at 10.35 GHz with a 3-dB bandwidth of 1.0037 GHz
and TZs at 9.42, 9.28 and 8.98GHz.

This article presents a miniaturized four-element MIMO
antenna for 5G mm-Wave communication. For optimum
performance, the antenna is designed on Rogers RT5880,
having a dielectric constant of 2.2, a loss tangent of
0.0009, and a substrate thickness of 0.508 mm. The antenna
element consists of a pentagon patch with double-ring slots
and a ground plane. The single antenna element is further
extended to design a two-element MIMO antenna and a
four-element MIMO antenna. In a four-element MIMO antenna
system, four symmetrical antennas are placed orthogonally,
and the inter-element separation is maintained at 0.2λ0 to
achieve an isolation of <-19dB at 28 and 38 GHz,
respectively. The proposed MIMO antenna covers 28/38GHz
bands with a gain of 3.92 dBi and 4.57 dBi at the resonant
frequencies, the diversity performance, such as envelope
correlation coefficient (ECC) are lower than 0.015, a
diversity gain (DG) exceeding 9.97 dB in both operating
bands. Additionally, the Mean Effective Gain (MEG) and
Total Active Reflection Coefficient (TARC) results further
confirm the suitability of the antenna for high-performance
MIMO applications. The numerical analysis is carried out
using CST Microwave Studio. These qualities highlight the
system’s applicability for 5G mm-Wave communication.

The design and analysis of a wearable antenna with a high
impedance surface (HIS) are presented in this study. On
denim fabric, a radiating patch is created by combining a
ring and a U-shaped resonator. The high impedance surface
(HIS) semifabric antenna uses a 3.5 GHz operating
frequency. When an antenna is placed on a human body, the
HIS is employed to shield it from back radiation. The
suggested antenna with HIS has dimensions of 66.8 x 66.8 x
4.84 mm. In addition to significantly lowering SAR value
and back radiation, HIS raises the standard wearable
antenna's gain from 2.06 dBi to 8.76 dBi. CST Studio is
used for the numerical analysis.

Abstract—We consider FMCW radar for vital sign detection
and monitoring using the spectral correlation function
(cyclostationary signal processing) for creating time
sliding 2D alpha-frequency map. The FMCW radar first
detects the peaks in the Range-Doppler (R-D) map, selects
detected targets and takes samples from the one of them
from the point in R-D. The extracted signal is nonlinear
frequency modulated with body movement, breath and hearth
rate. In general, the time domain signal taken from the
target in R-D map can be modeled as AM-FM modulated. The
body movement interferes with modulated components
generated by breathing and heart pulses. Cyclostationary
Features Detection (CFD) can separate useful signals form
the interference, because signal components modulated by
respiration and heart rate exhibit cyclostationarity. The
Spectral Correlation (SC) is applied for forming 2D
alpha-frequency maps that are sliding in time. The single
map can be processed by some of the AI methods or standard
classification. The results are presented for the ideal
baseband model represented by FM signal modulated by breath
and hearth rates. These results are compared with real
measurements taken from the mechanical device which
emulates breathing and heart biting. Finally, the
processing of the real measurements taken from the
deflected RF signal from humans is presented and analyzed.

This paper presents an analysis of H-plane waveguide
band-stop filters with resonators implemented on a
dielectric carrier inserted into the waveguide, focusing on
the influence of gap position and orientation of the
resonant elements on the scattering parameters. The
resonant elements are realized as rectangular metallic
structures with a capacitive gap. The frequency range of
interest is the X-band. Individual resonators are designed
and analyzed using full-wave electromagnetic simulations in
WIPL-D Pro CAD, while configurations with three resonators
inside the waveguide are evaluated using circuit-level
analysis in WIPL-D Microwave Pro. The main result of
interest is the influence of gap orientation on the
scattering parameters, complemented by a comparative
analysis of RLC equivalent circuit models and CAD-based
simulations.

Climate change is an ongoing and unavoidable process that
demands continuous monitoring and analysis. Anticipating
future environmental changes and mitigating associated
risks requires extensive observations and measurements
across diverse geographic locations. This growing need for
ubiquitous environmental monitoring is driving a shift from
expensive, specialized instrumentation toward low-cost,
integrated sensing solutions. In this context, this paper
evaluates the feasibility of using a commercially available
60 GHz Frequency-Modulated Continuous-Wave (FMCW)
millimeter-wave (mmWave) radar for environmental
characterization. This study focuses on analyzing the
radar’s capabilities and performance, as well as its
applicability in real-world scenarios that introduce
challenges not typically encountered in controlled
laboratory environments. The outcome of this work is the
identification of key limitations that require further
solutions, along with existing toolsets that are already
mature and can be directly leveraged for practical
deployment.

U ovom radu je prikazan sistem za analizu zauzetosti
prostora u marketima, realizovan na Rasbperry Pi uređaju.
Predloženi sistem koristi YOLO algoritam za detekciju
prisutnosti osobe i kameru postavljenu na Raspberry Pi koja
sistemu u realnom vremenu prenosi stanje svake zone
marketa. Sistem prati dnevnu zauzetost svake zone i na
kraju dana eksportuje prikupljene podatke. Podaci koje
projektovani sistem prikupi mogu poslužiti za dalju analizu
popularnosti i posećenosti određenih delova maloprodajnog
objekta u cilju poboljšanja poslovanja.