The intelligent transport system (ITS) has become one of the most globally researched topics with a lot of investment and development resources being dedicated into it due to its foreseen impact on the economic growth of the transport sector. Currently there are two main vehicle-to-everything (V2X) technologies, whose primary application is focused on ITS, backed up by the key players of various automotive, telecommunication and transport industries: dedicated short-range communications (DSRC) and cellular vehicle-to-everything (C-V2X), respectively based on IEEE 802.11p and 3GPP LTE/5G NR. While DSRC already has deployments, C-V2X is expected to see larger scale trails and deployments in 2020. In this work, the authors provide insight and review into two main V2X technologies, DSRC and C-V2X, their core parameters, shortcomings and limitations, and explore the need for integration of IoT-based technologies into modern ITS solutions. A comprehensive overview and analysis of currently commercially available V2X products, their sub-blocks and features is provided.

The thyristor-controlled reactor (TCR) compensator for smooth asymmetric compensation of reactive power in a low-voltage utility grid is proposed in this work. Two different topologies of compensator were investigated: topology based on a single-cored three-phase reactor and topology with separate reactors for every phase. The investigation of the proposed TCR compensator was performed experimentally using a developed experimental test bench for 12 kVAr total reactive power. The obtained results show that employment of separate reactors for every phase allows us to control the reactive power in every phase independently, and that the TCR compensator with three single-phase reactors is suitable for smooth and asymmetric compensation of reactive power in a low-voltage utility grid.

This paper presents the design, simulation, and measurements of a low power, low phase noise 10.25–11.78 GHz LC digitally controlled oscillator (LC DCO) with extended true single phase clock (E-TSPC) frequency divider in 130 nm complementary metal–oxide–semiconductor (CMOS) technology for 5G intelligent transport systems. The main goal of this work was to design the LC DCO using a mature and low-cost 130 nm CMOS technology. The designed integrated circuit (IC) consisted of two parts: the LC DCO frequency generation and division circuit and an independent frequency divider testing circuit. The proposed LC DCO consisted of the following main blocks: the high Q-factor inductor, switched-capacitors block, cross-coupled transistors, and the current control block. Inductors with switched-capacitors block formed an LC tank. The designed E-TSPC frequency divider consisted of eight blocks connected in a series; each block increased the division ratio by a factor of two. The frequency of the input signal was divided in the region from two to 256 times using the designed divider. The main parameters of the designed E-TSPC divider and the LC DCO measurements were given as follows: LC DCO achieved a wide tuning range from 10.25 GHz to 11.78 GHz (1.53 GHz, 15.28% bandwidth); phase noise at 1 MHz offset frequency from LC DCO lowest carrier frequency was −113.42 dBc/Hz; phase noise at 1 MHz offset frequency from LC DCO highest carrier frequency was −110.51 dBc/Hz; The average power consumption of the designed LC DCO core and E-TSPC divider were 10.02 mW and 97.52 mW, respectively; the figure of merit (FOM) and the extended FOM_T values of the proposed LC DCO were −183.52 dBc/Hz and −187.20 dBc/Hz, respectively. These FOM and FOM_T results were achieved due to very low phase noise (−113.52 dBc/Hz) and a wide frequency tuning range (15.28%). The total layout area including the pads was 1.5 mm × 1.5 mm, with the largest part of the layout occupied by the proposed LC DCO (193 µm × 311 µm). The largest part of the LC DCO was occupied by the inductor 184 µm × 184 µm. The manufactured chip was packed into a quad flat no-leads (QFN) 20 pads package.

This article presents a wideband reconfigurable integrated low-pass filter (LPF) for 5G NR compatible software-defined radio (SDR) solutions. The filter uses Active-RC topology to achieve high linearity performance. Its bandwidth can be tuned from 2.5 MHz to 200 MHz, which corresponds to a tuning ratio of 92.8. The order of the filter can be changed between the 2nd, 4th, or 6th order; it has built-in process, voltage, and temperature (PVT) compensation with a tuning range of ±42%; and power management features for optimization of the filter performance across its entire range of bandwidth tuning. Across its entire order, bandwidth, and power configuration range, the filter achieves in-band input-referred third-order intercept point (IIP3) between 32.7 dBm and 45.8 dBm, spurious free dynamic range (SFDR) between 63.6 dB and 79.5 dB, 1 dB compression point (P_1dB) between 9.9 dBm and 14.1 dBm, total harmonic distortion (THD) between −85.6 dB and −64.5 dB, noise figure (NF) between 25.9 dB and 31.8 dB and power dissipation between 1.19 mW and 73.4 mW. The LPF was designed and verified using 65 nm CMOS process; it occupies a 0.429 mm² area of silicon and uses a 1.2 V supply.

The increasing prevalence of sedentary lifestyles poses significant global health challenges, including obesity, diabetes, musculoskeletal disorders, and cardiovascular issues. This paper presents the design and development of a universal smart chair system aimed at mitigating the adverse effects of prolonged sitting. The proposed solution integrates a pressure sensor, vibration motors, an LED strip, and Bluetooth Low-Energy (BLE) communication into a modular and adaptable design. Powered by an STM32WB55CGU6 microcontroller and a rechargeable lithium-ion battery system, the smart chair monitors sitting duration and the user’s posture, and provides alerts through tactile, visual, and auditory notifications. A complementary mobile application allows users to customize sitting time thresholds, monitor activity, and assess battery status. Designed for universal compatibility, the system can be adapted to various chair types. Technical and functional testing demonstrated reliable performance, with the chair operating for over eight workdays on a single charge. The smart chair offers an innovative, cost-effective approach to improving workplace ergonomics and health outcomes, with potential for further enhancements such as posture monitoring. A pilot study with 83 students at VILNIUS TECH showed that the smart chair detected correct posture with 94.78% accuracy, and 97.59% of users responded to alerts by adjusting their posture within an average of 3.27 s.