Radio Receiver Research Articles

Методика обучения основам моделирования и практической реализации блоков многоканального приемного устройства

The paper presents methods of synthesis and research of the principles of functioning the radio-technical multichannel receivers in a case of a TMS320C5510 digital signal processor. The method of synthesizing a model 
 of an object of professional activity – a multichannel receiver - includes the following stages: theoretical study of the structure and principles of functioning of a digital multichannel receiver of a radio communication channel; computer modeling of the main processes in the receiving radio equipment in the Matlab environment; a laboratory experiment on developing and studying a model of a digital multichannel receiver on a laboratory stand DSK-5510. Conducting the research and the practical work on studying and synthesizing the object of professional activity in case of a model of a heterodyne radio receiver allows students, within the framework of one task, to gain theoretical knowledge about the structure and functioning of complex radio engineering systems, to master methods of radio measurements in digital equipment, to gain skills in technical diagnostics of hardware and software systems, to learn how to choose the measured technical parameters and control points. Introducing the research methods, which include both the theoretical study and computer modeling the processes in complex radio engineering systems, and practical implementing these systems on modern digital equipment in the educational process will increase the quality and efficiency of developing the professional competencies of the future graduates of the specialty “Technical Operation 
 of Transport Radio Equipment” and raise their competitiveness in the labor market.

Thermal Analysis of Coupled Resonant Coils for an Electric Vehicle Wireless Charging System

Electric vehicles use wireless energy transmission to obtain energy, which can effectively avoid the shortcomings of traditional methods. As the carrier of radio energy transmission and reception, the high temperature of the coil triggers the degradation of wireless transmission performance and the aging of the coil, which may cause fire and other safety problems in serious cases. This paper studied the temperature distribution of the magnetically coupled coil model for electric vehicles. Based on the study of the basic law of heat transfer, the coil model was established using ANSYS software, and the boundary conditions and relevant parameters were set. After many simulation experiments and comparisons, it was finally determined that the transmitting coil and the receiving coil were the same sizes, the inner diameter of the coil was 100 mm, the outer diameter of the coil was 181 mm, and the coupling distance between the transmitting coil and the receiving coil was set to 60 mm. Coil models were simulated and analyzed using different materials. The simulation results show that after 30 min of system operation, the material chosen from the temperature range may have been gold, silver, copper, or aluminum, but from the comprehensive consideration of cost and performance, the material of the coil in the model was finally set to copper. Copper was the best material; its temperature maximum was 74.952 °C and lower than the safety value of 80 °C. It is hoped that this study will provide a reference for wireless charging coil design.

Finding gadgets in incremental code updates for return-oriented programming attacks on resource-constrained devices

Code-reuse attacks pose a threat to embedded devices since they are able to defeat common security defences such as non-executable stacks. To succeed in his code-reuse attack, the attacker has to gain knowledge of some or all of the instructions of the target firmware/software. In case of a bare metal firmware that is protected from being dumped out of a device, it is hard to know the running instructions of the target firmware. This consequently makes code-reuse attacks more difficult to achieve. This paper presents a novel approach how an attacker can gain knowledge of some of these instructions by sniffing unencrypted incremental updates. These updates exist to reduce the radio reception power for resource-constrained devices. It will be demonstrated how a return-oriented programming (ROP) attack can be accomplished on a MSP430 MCU using only the passively sniffed incremental updates. The generated updates of the R3diff and Delta Generator (DG) differencing algorithms will be under assessment. The evaluation reveals that both of them can be exploited by the attacker and how an attacker can maximize his information gain when dealing with more than one update. It also shows that the DG generated updates leak more information than the R3diff generated updates. This stresses the fact that even delta updates need to be protected with encryption. To defend against this attack, different countermeasures that consider different power consumption scenarios are proposed, but yet to be evaluated.

Моделирование тонкопленочной печатной катушки индуктивности для УКВ радиоприемника

When designing and modeling inductors, the only practical options are wire connections and flat geometric shapes, although, wire connections allow to achieve a high-quality factor, their inductance values are limited and can be quite sensitive to variations, flat spiral inductors have limited values, but have inductance, which is well defined in a wide range of process variations. The application of the program Ansoft Maxwell in the simulation of a thin-film printed coil for VHF radio receiver in the perspective of use on a stationary research platform located in the coastal zone of the Black Sea in the Blue Bay at a distance of ~ 450 m from the shore. Work in the future is aimed at using the software product for the full cycle of modeling the minimized element base of the receiving and transmitting equipment.

Elite-CAM: An Elite Channel Allocation and Mapping for Policy Engine over Cognitive Radio Technology in 5G.

The spectrum allocation in any auctioned wireless service primarily depends upon the necessity and the usage of licensed primary users (PUs) of a certain band of frequencies. These frequencies are utilized by the PUs as per their needs and requirements. When the allocated spectrum is not being utilized in the full efficient manner, the unused spectrum is treated by the PUs as white space without believing much in the concept of spectrum scarcity. There are techniques invented and incorporated by many researchers, such as cognitive radio technology, which involves software-defined radio with reconfigurable antennas tuned to particular frequencies at different times. Cognitive radio (CR) technology realizes the logic of the utility factor of the PUs and the requirements of the secondary users (SU) who are in queue to utilize the unused spectrum, which is the white space. The CR technology is enriched with different frequency allocation engines and with different strategies in different parts of the world, complying with the regulatory standards of the FCC and ITU. Based on the frequency allocation made globally, the existing CR technology understands the nuances of static and dynamic spectrum allocation and also embraces the intelligence in time allocation by scheduling the SUs whenever the PUs are not using the spectrum, and when the PUs pitch in the SUs have to leave the band without time. This paper identifies a few of the research gaps existing in the earlier literature. The behavioral aspects of the PUs and SUs have been analyzed for a period of 90 days with some specific spectrum ranges of usage in India. The communal habits of utilizing the spectrum, not utilizing the spectrum as white space, different time zones, the requisites of the SUs, the necessity of the applications, and the improvement of the utility factor of the entire spectrum have been considered along with static and dynamic spectrum usage, the development of the spectrum policy engine aligned with cooperative and opportunistic spectrum sensing, and access techniques indulging in artificial intelligence (AI). This will lead to fine-tuning the PU and SU channel mapping without being hindered by predefined policies. We identify the cognitive radio transmitter and receiver parameters, and resort to the same in a proposed channel adaption algorithm. We also analyze the white spaces offered by spectrum ranges of VHF, GSM-900, and GSM-1800 by a real-time survey with a spectrum analyzer. The identified parameters and white spaces are mapped with the help of a swotting algorithm. A sample policy has been stated for ISM band 2.4 GHz where such policies can be excited in a policy server. The policy engine is suggested to be configured over the 5G CORE spectrum management function.

Taking Time to Unwind

AbstractSummer has arrived, and the busy season of Display Week is in the rearview mirror. I'm writing this at a picnic table from our summer camp in the Berkshire mountains, where (for a little while) I can escape the demands and sounds of civilization. We have marginal internet and some radio reception, but mostly the background soundtrack is birds and breezes in the trees.

Use of Traffic Signal Lights in Vehicle– to– Vehicle Communication on Underground Mine Ramps

To minimise collisions and road accidents, road safety systems require Vehicle– to– Vehicle (V2V) and Vehicle– to– Road (V2R) communication infrastructure. Two-way traffic flow dynamics in single-lane underground mine haulage ramps do affect productivity of ramp in times of ore transportation to the surface for processing. Optical wireless communication offers no health hazard, low power consumption, non-licensed channels and high bandwidth. In this research, V2V communication on an underground mine ramp has been actualised making use of traffic signal lights, Radio Frequency (RF) Transmitters (Tx) and Receivers (Rx), and a traffic signal lights module. Simulation outcomes confirm orderly movement of two heavy vehicles on the haulage ramp. This development stands to minimise the incidents occurrence rate in mine ramp haulage systems.

Математическая модель идентификации космических аппаратов

Proposed below is a mathematical model for reception and processing of spurious (“uncontrolled” radiation) from constantly operating units of the special complex installed onboard a spacecraft. This model makes it possible to implement a new technique for identification of such radiation thus improving the capabilities of the space monitoring. At the same time creation of stand-alone radio systems solely for identification of the spacecrafts based on the proposed mathematic model would require significant expenses therefore it is worthwhile to add new identification hardware to the existing ground-based radio systems used for space flight control. Identifying features in the proposed mathematical model are the parameters of signals of the uncontrolled radiation from constantly operating units installed onboard spacecrafts that “leak” through antenna systems (master generators, heterodyne oscillators in the spacecraft radio receivers). Identification of spacecrafts by uncontrolled radiation from the receiving master generators and heterodyne oscillators involves keeping track of the behavior of oscillation parameters as well as identifying signs that distinguish the oscillations of one generator from another. Since the uncontrolled radiation from heterodyne oscillators is a harmonic oscillation, it features such parameters as amplitude, frequency and initial phase. It is impossible to use the amplitude and initial phase of the signal for identification purposes because the propagation medium strongly affects these parameters. The most informative for identification purposes is the frequency of oscillations, or rather, the behavior of the frequency changes over time. These changes are due to the frequency instability of the onboard master generators. The behavior of the frequency change depends on the characteristics of each onboard generator, which serves as a basis for identification. It should be noted that the identification process can be conditionally divided into two stages: the first stage includes validation of models and processing (evaluation) algorithms while the second stage involves classification of the results of processing (evaluation).

Analysis and Modeling of a Directional Microwave Coupler as SMD Component

The article describes the calculation, modeling and layout of the directional coupler. In the course of the work the market analysis was carried out, the model of directional coupler in the frequency range of 2.9—4.5 GHz, the layout of the device and measuring equipment were developed. Directional couplers with different transient attenuation are widely used in the distribution circuits of antenna arrays, as well as to control the power of the radio signal propagating in the transmission line, in power meters, automatic gain control systems, radio receivers, etc. The choice of circuit solutions used for the construction of directional couplers is carried out depending on the specific technical requirements for electrical parameters, the range of operating frequencies and the capabilities of the technological base. Practically all variety of structures of directional couplers realized on elements is a result of modification of the simplest structures. The main types of directional taps include stub, single-stage and tandem-based. During the simulation, it turned out that the directional coupler based on a tandem connection of two connected transmissions with the location of the transmission lines on different layers of the multilayer printed section was suitable for this work. This is due to the fact that when modeling the directional coupler with transmission lines on one printed circuit board, The gap between these lines is too small (&10 nm), which is extremely difficult to perform on a microstrip structure.

An accurate and reliable positioning methodology for land vehicles in tunnels based on UWB/INS integration

At present, the global navigation satellite system (GNSS) is the most widely used technology in the field of vehicle navigation and positioning. However, due to satellite signal blocking, it can be challenging to obtain precise and reliable vehicle positions in completely GNSS-denied environments. In this paper, a positioning strategy utilizing ultra-wide band (UWB) and a low-cost MEMS inertial navigation system (INS) is proposed, aimed at tracking vehicles in typical GNSS-denied scenarios. UWB tech has potential for high-precision ranging due to its strong penetration ability. However, non-line-of-sight (NLOS) propagation still has a high occurrence in typical traffic scenarios due to the fact that the direct path between the radio transmitter and the radio receiver is obstructed. Therefore, a two-step NLOS error mitigation method is proposed to deal with the abnormal measurements of UWB in tunnels. First, a state-of-the-art probabilistic factor graph model is proposed to estimate the vehicle’s position information based on UWB range measurements instead of excluding the NLOS reception. Then, a residual weighting algorithm is employed during UWB/INS loosely coupled integration to further mitigate the NLOS error. Finally, the performance of the proposed methodology is evaluated through experiments. Experiments conducted in the typical NLOS environment of Nanjing show that the proposed method can achieve higher positioning accuracy when compared with the conventional UWB/INS integration.

ULTRA-WIDEBAND RADIO RECEIVER OF THE MEASURING SYSTEM OF THE MICROWAVE RANGE

The purpose of the article is to substantiate the method and circuit design option for constructing an ultra-wideband radio receiver of the measuring system, mathematical modeling of the main parameters of the receiving path. It is shown the block diagram and general characteristics of the receiver. Including the dynamic range of received signals 111 dB, operating frequency range from 1 to 18 GHz. The article discusses the components of the receiver, such as: an automatic power control unit with a dynamic range of 50 dB and a tuning step of 1 dB, a preselector with six bandwidths 1–2,5; 2,5–4; 4–6; 6–11; 11–15; 15–18 GHz and a frequency conversion unit with three conversion steps. The structure is substantiated and the parameters of each of the blocks are given. A frequency conversion scheme with a final intermediate frequency of 0.75 GHz and a bandwidth of 500 MHz is considered in detail. Modeling of the noise figure, the distribution of the signal level along the receiver path from the input signal level and the results of modeling the output signal of the IF receiver.

CMOS-MEMS Vibro-Impact Devices and Applications

CMOS-MEMS-based vibro-impact devices that utilize impact-induced nonlinear dynamics have been shown to yield unique and unprecedented functionalities with on-chip integration capability. For example, a 0.35-µm CMOS-based capacitively transduced comb-driven folded-beam resonant switch has been integrated with backend circuits to demonstrate a zero-quiescent power wireless receiver operating at the low-frequency (LF) band. In addition, CMOS-MEMS vibro-impact resonators have been used as AFM-alike surface condition monitoring for detecting chemical coating on structural sidewalls and clock generators with controllable duty cycles by manipulating the actuation conditions. This article will review these achievements and discuss the limitations and challenges in developing the vibro-impact devices using the CMOS-MEMS technology.

Consolidated Amateur Radio Signal Reports as Indicators of Intense Sporadic E Layers

A case study is presented which demonstrates the value and validity of a novel approach to the use of consolidated amateur (‘ham’) radio reception reports as indicators of the presence of intense ionospheric sporadic E (Es). It is shown that the use of amateur data can provide an important supplement to other techniques, allowing the detection and tracking of Es where no suitable ionosonde or other measurements are available. The effectiveness of the approach is demonstrated by reference to ionosonde data, and the advantages and limitations of the technique are discussed.

Wideband Continuous-Time MASH Delta-Sigma Modulators: A Tutorial Review

The maximum sampling frequency of oversampled continuous-time (CT) delta-sigma modulators (DSM) has increased considerably over the past decade. Plus, with its implicit anti-aliasing filtering and resistive input impedance, it results in a substitution of discrete-time pipeline ADCs in wireless receivers. For CT DSMs, multi-stage noise-shaping (MASH) topology features a cascade of low-order loops, thus allowing the exploration of larger sampling rate when compared with a single-loop topology. However, the inherent quantization noise (QN) leakage constrains the achievable resolution of the MASH DSM. Besides, the QN extraction of preceding stages is problematic in CT MASH with very fast sampling rates. This brief review the fundamentals and design considerations of CT MASHs. It highlights recent state-of-the-art CT MASH addressing the above design challenges, including architectural advances, circuitry innovation and digital calibration. This brief intends to serve as a starting point in the forthcoming development of a wideband low-power CT MASH DSM.

Realization of multiband communications using different Rydberg final states

Rydberg atoms can serve as an atomic radio frequency receiver for digital and analog information transmission. In this paper, a ladder-type electromagnetically induced transparency system is prepared in a room temperature cesium atomic vapor cell. Microwave electric fields in the Ku band at a frequency of 12.52 GHz and the Ka band at a frequency of 39.80 GHz are used as two-channel communication carriers to demonstrate concurrent information transmission. Analog and digital communications are demonstrated by performing audio and pseudo-random binary sequence signal transmission, respectively. The dynamic range of the proposed system is ∼50 dB, and the communication bandwidth is more than 10 MHz. The obtained results demonstrate the fundamental principles of two- or multi-band communication systems based on different Rydberg final states.

A Deep Learning-Based Intelligent Receiver for Improving the Reliability of the MIMO Wireless Communication System

Multiple-input–multiple-output (MIMO) technology is one of the most widely used communication technologies. However, with the increasing number of antennas, the complexity of the MIMO wireless communication receiver becomes higher and higher. On the other hand, the complex communication channels also raise up a great challenge to the reliability of the communication receiver system. With the rapid development and wide application of deep learning, it has been applied in the field of communication to solve some problems that are difficult to solve by the traditional methods, and thereby, improves the reliability of communication systems. Inspired by this idea, this article reviewed the signal processing process of the MIMO receiver system from the perspective of system reliability. Based on deep learning, the signal processing modules of the receiver system are jointly optimized, which changes the information recovery process of the traditional receiver and proposes the intelligent receiver for MIMO communication. In order to verify the system reliability of the intelligent receiver, this article analyzes it from the aspects of antenna numbers and channel conditions. The influence of different implementation methods of the intelligent receiver on the system reliability is also analyzed. Simulation results show that the proposed intelligent receiver for the MIMO wireless communication can recover information with a lower bit error rate and higher reliability compared with the traditional receiver under different conditions and antenna configurations.

An Enhanced Pedestrian Dead Reckoning Aided With DTMB Signals

Pedestrian Dead Reckoning (PDR) is a good alternative positioning method in Global Navigation Satellite Systems (GNSS)-challenged environments. It has the advantage in terms of infrastructure-independent, while the disadvantage is that, the estimated errors grow rapidly with time. The Digital Terrestrial Multimedia Broadcasting (DTMB) signals have strong transmission power, which contributes to better urban propagation and building penetration than GNSS signals. So, in this paper, an enhanced PDR algorithm aided with DTMB signals is proposed. In the study, a complete software-defined radio receiver is developed to estimate the Doppler speed and range information from DTMB signals. To reduce the accumulated errors of the PDR, the Extended Kalman Filter (EKF) algorithm is carried out to fuse the information of Doppler speed and ranging from the DTMB signals, as well as the information of walking speed and heading from the PDR. The results of the field tests showed that the 95% positioning error of the proposed algorithm is less than 3.94 m, while the PDR only is less than 9.19 m, which suggests the effectiveness of the proposed method to provide continuous positioning by fusing DTMB signals with PDR.

Is LEO-Based Positioning with Mega-Constellations the Answer for Future Equal Access Localization?

Capital expenditures and indoor challenges are two of the main obstacles toward equal access positioning services worldwide. Global Navigation Satellite Systems (GNSS) do not function well indoors and in some challenging outdoor scenarios, such as dense forest canopies or hilly terrains rich in vegetation due, for example, to multipaths and low carrier-to-noise ratios. Terrestrial solutions nowadays can be used to complement GNSS, but they are typically costly to deploy with high coverage and do not offer equal access, for example in some low-revenue countries, in regions forbidding wireless 5G access due to health concerns, or in areas hard to reach with terrestrial infrastructure, such as deep jungle, desert areas with sandy dunes, and deep valleys/deep canyons. As many low Earth orbit (LEO) mega-constellations are emerging and their satellites are significantly closer to Earth than GNSS satellites, solutions based on LEO could complement GNSS. LEO-based communications are expected to be widespread in the next decade, and they will offer a global and easy-to-access infrastructure, with the main costs to the end user coming from the receiver equipment. It is our assumption that future wireless receivers will support the integration of terrestrial and satellite infrastructure, and thus, the LEO-based positioning tasks could be mainly implemented as software add-ons on existing future receivers. Nevertheless, closer proximity to Earth does not automatically mean stronger received signals or acceptable positioning accuracy, especially when the carrier frequencies of the new LEO signals are higher than those in GNSS. Here, we present a feasibility study of LEO-based equal access localization by looking at the current opportunities, benefits, and challenges of LEO megaconstellations used as signals of opportunities. We show that there is an unharnessed potential of future LEO megaconstellations for equal access localization, although several challenges are still to be overcome.

Conductor less Bus Ticketing System Using RFID Technology

Abstract: The main objective of this paper is to generate passenger tickets using RFID technology for the fare of a particular destination. The appropriate amount is deducted from the RFID card. In addition to that, in proposal system RFID has proven to be one of the most promising technologies in recent years and can be effectively employed in various applications since it is economical and widely used tool for tracking and locating purposes. Radio-frequency identification (RFID) is a technology that uses electromagnetic fields to automatically identify and track tags attached to objects .A small radio transponder, a radio receiver, and a radio transmitter make up an RFID system The RFID application, on the other hand, has become a popular tool for both tracking transit vehicles and the public ticketing system.

Acousto-optic frequency shifter-based microwave photonic channelized receiver using a single optical frequency comb.

A microwave photonic channelization receiver is a promising technology for broadband radio frequency (RF) signal monitoring and reception. In this Letter, by exploiting acousto-optic frequency shifters (AOFSs), a microwave photonic channelization receiver is proposed. The proposed microwave photonic channelized receiver can reduce dual coherent optical frequency comb (OFC) generators with detuning frequency spacing into a single OFC generator. To verify the feasibility of the proposed channelization scheme, a broadband RF signal with 3.2 GHz bandwidth is channelized into eight narrowband RF signals with 0.4 GHz bandwidth. Moreover, we investigate the effect of the tuning error imposed by AOFSs, where the error vector magnitude (EVM) of subchannels is obtained by channelizing the four 16-quadrature amplitude modulation (16-QAM) signals into four subchannels.