Multimode HMSIW-based bandpass filter with improved selectivity for fifth-generation (5G) RF front-ends

This article presents the detailed theoretical, simulation, and experimental analysis of a half-mode substrate integrated waveguide (HMSIW)-based multimode wideband filter. A third-order, semicircular HMSIW filter is developed in this paper. A semicircular HMSIW cavity resonator is adopted to achieve wide band characteristics. A U-shaped slot (acts as a lambda/4 stub) in the center of a semicircular HMSIW cavity resonator and L-shaped open-circuited stubs are used to improve the out-of-band response by generating multiple transmission zeros (TZs) in the stop-band region of the filter. The TZs on either side of the passband can be controlled by adjusting dimensions of a U-shaped slot and L-shaped open-circuited stubs. The proposed filter covers a wide fractional bandwidth, has a lower insertion loss value, and has multiple TZs (which improves the selectivity). The simulated response of filter agrees well with the measured data. The proposed HMSIW bandpass filter can be integrated with any planar wideband communication system circuit, thanks to its planar structure.This work is partially supported by RTI2018-095499-B-C31, funded by Ministerio de Ciencia, Innovacion y Universidades, Gobierno de Espana (MCIU/AEI/FEDER, UE)

RF Transceiver Design For 3G Cellular Communications

A Radio frequency (RF) transceiver is designed for UMTS Terrestrial Radio Access (UTRA) Frequency Division Duplexing (FDD) Wideband-Code Division Multiple Access (W-CDMA) user equipment (UE) and the respective performance analysis is presented in this thesis. The performance analysis is conducted through simulation and measurement towards the 3GPP specifications. This Rf front end mobile transceiver provides the function of modulation and demodulation of the 3G cellular communications digital signal in the air link. It is implemented with a commercial standard dual conversion transmitter operating at 1920MHz to 1980MHz and a heterodyne receiver operating at 2110MHz to 2170MHz. The Transceiver consists of power amplifier (PA), variable gain power amplifier driver, low noise amplifier (LNA), autimatic gain control (AGC) amplifier, mixers (up conversion and down conversion), modulator, demodulator and frequency synthesizer (with oscillator and phase lock loop) as the main building blocks. All these modules are commercially available in the market. The main RF parameters of the transceiver such as adjacent channel leakege ratio (ACLR), occupied bandwidth, output power, noise figure (NF), gain , third order input intercept point (IIP3) and selectivity are simulated and measured against the stringent requirements in the 3GPP specifications. Agilent Advanced Design System (ADS) Version 1.5 with 3GPP Design Library is used as an initial simulation tool. Based on the simulation results, suitable modules are acquired and cascaded into a laboratory prototype. The performance of the prototype developed is analysed through a series of measurements. The transceiver was found to be compliant to the 3GPP standard. the transmitter has a measured maximum output power of +23.6dBm, EVM of 6.45 percent ( when Pin= -20dBm), ACLR ( at 5MHz offset) of approximately -37dBc and an occupied bandwidth of 4.159 MHz when operating at 1950MHz. The receiver achieve a NF of 6.71dB and IIP3 of -14.9dBm at maximum gain of 92dB in the baseband I and Q output and could detect a signal level as low as -117.3 dBm with a bit error rate (BER) of less than 10-3 when operating at 2140Mhz. This transceiver is powered from a 3 cells NiMH battery pack at 3.6V ( 700mA

Design of RF amplifiers and down-conversion mixer for Ultra-Wideband transceiver

The Ultra-Wideband (UWB) system has emerged as a major solution for wireless communication due to its wide bandwidth and high data rate. As the deployment of UWB gathers pace, consumer electronic devices, PC peripherals and mobile devices manufacturers are striving to develop their first cost effective system-on-a-chip (SOC) transceiver. In this work, the design and implementation of the three main building blocks in a radio frequency (RF) transceiver, namely power amplifier (PA), low noise amplifier (LNA) and mixers that fully complies with the compulsory band for UWB MB-OFDM (3.168 to 4.752 GHz) specifications are presented. Employing 0.18 µm RF CMOS technology, the proposed LNA, PA and mixer are systematically analyzed, simulated, fabricated and measured. The proposed single-stage LNA is based on two transistors cascode topology. Source inductive degeneration and interstage inductor are employed to increase the overall broadband gain while maintaining a low noise figure. The proposed PA uses two-stage common source (CS) architecture, also with inductive degeneration. Finally, an inductorless mixer using the conventional single-balanced topology with active baluns is implemented, using low and high-side LO injections

Performance Evaluation of Enhanced EXPRULE Scheduler for LTE Multi Cell Network

Nowadays, the demand for high data rate in the Long Term Evolution (LTE) network is rapidly increasing. The vast deployment of real-time services in LTE network increases rapidly. To support such demand, beside the vast update from 3G to 4G, LTE network implements several techniques such as handover and scheduling techniques to support the Quality of Service (QoS) requirements for UEs. One of the challenges in LTE network is the UEs mobility management. The services to UEs shall remain stable while the UEs are moving from one cell to another. In this paper, we analyzed the performance of the proposed eEXPRULE scheduler for LTE network in multiple cell scenario while the UEs are randomly move from one cell to another with different speeds. Extensive simulations are carried out using LTE-Sim simulator. The proposed eEXPRULE improves the performance of video traffic. It improves the video throughput (16%), video PLR (50%), video delay, VoIP delay (62%), and spectrum efficiency over the existing schedulers

Dimmable WiFi-connected LED driver with android based remote control

A wireless controllable LED dimming system with an android remote control is proposed. The whole system consists of a constant current LED driver based on buck converter with LM3409HV buck controller, a microcontroller with wireless transceiver and Android smartphone as remote control. The wireless control signal from Android remote control is sent and microcontroller is used to decode the control signal and generate PWM dimming signal to LED driver, and thus, to control the LED's brightness. An android remote control application is developed and installed in an android smartphone. The experiment results show the energy efficiency of the proposed wireless controllable LED system

Design of IoT Health and Social Distancing Monitoring System

Since the outbreak of the COVID 19 pandemic, many companies have to deploy working from home. As the pandemic recovers, companies slowly start to adapt to the situation by making the workers work from the office. This is an effort to reduce the risks of spreading diseases in the workplace. This project aims to support that initiative and introduce a system that can control the risks of infection among workers. The proposed system monitors the health condition of the users and controls the social distancing at the workplace by using IoT technology and machine learning

0.18 mu m CMOS power amplifier for Ultra-wideband (UWB) system

This paper presents the design and implementation of a single-stage and double-stage power amplifier (PA) for UWB communication system. The proposed PAs are implemented in 0.18 mu m CMOS integrated circuit technology for a 3.1-4.8GRz UWB system. The single-stage PA achieves a simulated maximum power gain of +10.4dB at an input P1dB of -5.5dBm while consuming 23.0mW of DC dissipation at a DC supply of 1.0V. Two double-stage PAs have been designed based on the single-stage PA topology. Simulation results for both the double-stage PAs show a maximum power gain of +15.5dB and +24.1dB respectively with the power consumption of 35.5mW and 26.7mW separately. Results obtained from this study can be used as a reference design for future multi-stage UWB PAs implementation

A Hybrid Solar-RF Energy Harvesting System Based on an EM4325-Embedded RFID Tag

: This paper presents the deployment of a hybrid energy harvesting system that combines a wireless energy harvesting (EH) system and a 6 V, 170 mA monocrystalline solar energy derived from the Sun’s rays. The hybrid energy harvesting (HEH) system comprises the rectifier, the solar cell panel, the charging circuit, and the EM4325 embedded RFID tag. This study aims to design an efficient EH system capable of increasing the read range of an active RFID tag. The proposed approach integrates a meandered line radio frequency identification (RFID) tag with an EM4325 IC chip as the receiver antenna. A halfwave doubler RF rectifier circuit is connected to the antenna using a 50 Ω SMA connector to convert the captured RF waves into usable electrical power. A solar energy charging module equipped with a Maximum Power Point Tracking (MPPT) system, a rechargeable lithium-ion battery, and a DC-DC converter is configured to manage and store the harvested energy efficiently. The UHF tag antenna operates at 919 MHz, achieving a peak gain of 3.54 dB. The proposed rectenna achieves a maximum measured harvested power conversion efficiency (PCE) of 55.14% for an input power (Pin) of 15 dBm at a distance of 5.10 cm, while the solar cell panel realizes 3.92 W of power. Experimental results demonstrate the hybrid harvester system’s effectiveness, achieving a PCE of 86.49% at an output voltage (VDC) of 5.35 V. The main advantage of this approach is the creation of a compact hybrid RF and solar EH system by combining the solar cell panel with the antenna, thus enabling multi-functionality

SIW Cavity Backed Self-Quadruplexing Antenna For Compact RF Front-ends

A compact quarter-mode substrate integrated waveguide (QMSIW) based self-quadruplexing antenna is proposed for compact RF front-ends. The QMSIW based self-quadruplexing antenna has four unequal resonators resonating at the Industrial, Scientific and Medical (ISM) band (2.45 GHz), fifth-generation (5G) band (3.5 GHz), Wireless Local Area Network (WLAN) band (4.9 GHz) and Wireless Fidelity (WiFi) band (5.4 GHz). All four resonators radiate through the open-ended wall of the QMSIW resonator and the arc-shaped slot inside the cavity. By properly optimizing the locations and dimensions of the resonators, higher isolation ( > 29.9 dB) is gained. In fact, all four resonators operate on a common grounded substrate with negligible interference. A dummy rectangular device is used to keep the PCB and antenna in it to measure S-parameters and radiation properties. The proposed antenna has lower circuit size (0.23 λ2g ), reasonable gain ( > 3.85 dBi), high efficiency ( > 82.7 \%), and high isolation ( > 29.9 dB). Based on the above attributes, it is a good candidate for compact RF Front-ends