Low-Cost Mini Radar: Design Prototyping and Tests

Radar systems are largely employed for surveillance of wide and remote areas; the recent advent of drones gives the opportunity to exploit radar sensors on board of unmanned aerial platforms. Nevertheless, whereas drone radars are currently available for military applications, their employment in the civilian domain is still limited. The present research focuses on design, prototyping, and testing of an agile, low-cost, mini radar system, to be carried on board of Remotely Piloted Aircraft (RPAs) or tethered aerostats. In particular, the paper faces the challenge to integrate the in-house developed radar sensor with a low-cost navigation board, which is used to estimate attitude and positioning data. In fact, a suitable synchronization between radar and navigation data is essential to properly reconstruct the radar picture whenever the platform is moving or the radar is scanning different azimuthal sectors. Preliminary results, relative to tests conducted in preoperational conditions, are provided and exploited to assert the suitable consistency of the obtained radar pictures. From the results, there is a high consistency between the radar images and the picture of the current environment emerges; finally, the comparison of radar images obtained in different scans shows the stability of the platform.

Download Full-text

Diffuse reflectance spectroscopic analysis of barium sulfate as a reflection standard within 173–2500 nm: From pure to sintered form

Journal of Near Infrared Spectroscopy ◽

10.1177/0967033519868241 ◽

2019 ◽

Vol 27 (6) ◽

pp. 393-401

Author(s):

Abdul Halim Poh ◽

Mohd Fadzil Jamaludin ◽

Iman Aris Fadzallah ◽

Nik Muhd Jazli Nik Ibrahim ◽

Farazila Yusof ◽

...

Keyword(s):

Barium Sulfate ◽

Diffuse Reflectance ◽

Spectroscopic Analysis ◽

Low Cost ◽

Salt Form ◽

Pure Salt ◽

The Stability ◽

High Consistency ◽

High Reflection

The use of barium sulfate (BaSO4) as a low-cost reflectance standard has been documented for some time. In its pure salt form, the optical characteristics do have advantages compared to laboratory-grade sintered polytetrafluoroethylene (PTFE). However, its practical use has little advantage against the stability of PTFE. In this paper, a process of producing pelletized BaSO4, and characterization of its optical reflectance properties is reported. In its sintered form, data-driven analysis shows that BaSO4 is a commendable low-cost, high-reflection and a high-consistency material. The current sintered forms, though crude, registers a relatively stable texture to withstand minor mechanical stress, while having up to an average 92% reflectivity across the UV-VIS-NIR range (173–2500 nm) compared to a PTFE reflection standard.

Download Full-text

Low-cost eWLB packaging for automotive radar MMICs in the 76–81 GHz range

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078712000621 ◽

2013 ◽

Vol 5 (1) ◽

pp. 25-34 ◽

Cited By ~ 5

Author(s):

J. Böck ◽

M. Wojnowski ◽

C. Wagner ◽

H. Knapp ◽

W. Hartner ◽

...

Keyword(s):

System Integration ◽

Low Cost ◽

Wafer Level ◽

Automotive Radar ◽

Package Design ◽

Radar Sensors ◽

Radar Systems ◽

Plastic Package ◽

Rf Performance ◽

Near Future

Embedded wafer-level ball grid array (eWLB) is investigated as a low-cost plastic package for automotive radar applications in the 76–81 GHz range. Low transmission losses from chip to package and board are achieved by appropriate circuit and package design. Special measures are taken to effectively remove the heat from the package and to optimize the package process to achieve automotive quality targets. A 77 GHz radar chip set in eWLB package is developed, which can be applied on the system board using standard solder reflow assembly. These radar MMICs provide excellent radio frequency (RF) performance for the next generation automotive radar sensors. The potential for even higher system integration is shown by a radar transceiver with antennas integrated in the eWLB package. These results demonstrate that eWLB technology is an attractive candidate to realize low-cost radar systems and to enable radar safety affordable for everyone in the near future.

Download Full-text

Radar target simulator with complex-valued delay line modeling based on standard radar components

Advances in Radio Science ◽

10.5194/ars-16-203-2018 ◽

2018 ◽

Vol 16 ◽

pp. 203-213 ◽

Cited By ~ 5

Author(s):

Andreas R. Diewald ◽

Manuel Steins ◽

Simon Müller

Keyword(s):

Delay Line ◽

Low Cost ◽

Radar Target ◽

Ism Band ◽

Radar Sensors ◽

Radar Systems ◽

Complex Valued ◽

Theoretical Foundations ◽

24 Ghz ◽

Filtering Approach

Abstract. With increasing radar activities in the automotive, industrial and private sector, there is a need to test radar sensors in their environment. A radar target simulator can help testing radar systems repeatably. In this paper, the authors present a concept of low-cost hardware for radar target simulation. The theoretical foundations are derived and analyzed. An implementation of a demonstrator operating in the 24 GHz ISM band is shown for which the dynamical range simulation was implemented in a FPGA with fast sampling ADCs and DACs. By using a FIR filtering approach a fine discretization of the range could be reached which will furthermore allow an inherent and automatic Doppler simulation by moving the target.

Download Full-text

Multi-frequency sensor for remote measurement of breath and heartbeat

Advances in Radio Science ◽

10.5194/ars-4-79-2006 ◽

2006 ◽

Vol 4 ◽

pp. 79-83 ◽

Cited By ~ 14

Author(s):

M. Jelen ◽

E. M. Biebl

Keyword(s):

Doppler Radar ◽

Low Cost ◽

Remote Measurement ◽

Range Resolution ◽

Radar Sensors ◽

Pulse Radar ◽

Radar Systems ◽

Frequency Sensor ◽

24 Ghz

Abstract. Remote measurement of breath and heartbeat is desirable in many situations. It avoids the discomfort resulting from electrodes applied on the skin for long-term patients or during sports acvtivities. Also, surveillance of high security areas or finding survivors of disasters are interesting applications. Common methods identify the movement of heart and thorax by using the range resolution provided by UWB pulse radar systems. In this paper a low-cost approach is presented, that is based on detection of movement by means of Doppler radar sensors. Combining three sensors working in the ISM bands at 433 MHz, 2.4 GHz and 24 GHz, the presence of persons was reliably detected and the frequency of breath and heartbeat was measured.

Download Full-text

Portable Microwave Radar Systems for Short-Range Localization and Life Tracking: A Review

Sensors ◽

10.3390/s19051136 ◽

2019 ◽

Vol 19 (5) ◽

pp. 1136 ◽

Cited By ~ 13

Author(s):

Zhengyu Peng ◽

Changzhi Li

Keyword(s):

System Integration ◽

Short Range ◽

Continuous Wave ◽

Low Cost ◽

Consumer Electronics ◽

Radar Sensors ◽

Microwave Radar ◽

Radar Systems ◽

Driving Assistance ◽

Cw Radar

Short-range localization and life tracking have been hot research topics in the fields of medical care, consumer electronics, driving assistance, and indoor robots/drones navigation. Among various sensors, microwave and mm-wave continuous-wave (CW) radar sensors are gaining more popularity in their intrinsic advantages such as simple architecture, easy system integration, high accuracy, relatively low cost, and penetration capability. This paper reviews the recent advances in CW radar systems for short-range localization and life tracking applications, including system improvement, signal processing, as well as the emerging applications integrated with machine learning.

Download Full-text

Estimation of fractional cycle bias for GPS/BDS-2/Galileo based on international GNSS monitoring and assessment system observations using the uncombined PPP model

Satellite Navigation ◽

10.1186/s43020-021-00039-x ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Jin Wang ◽

Qin Zhang ◽

Guanwen Huang

Keyword(s):

Estimation Method ◽

Satellite Orbit ◽

Satellite System ◽

Assessment System ◽

Navigation Satellite ◽

Dual Frequency ◽

Fractional Cycle Bias ◽

The Stability ◽

High Consistency ◽

Global Navigation Satellite

AbstractThe Fractional Cycle Bias (FCB) product is crucial for the Ambiguity Resolution (AR) in Precise Point Positioning (PPP). Different from the traditional method using the ionospheric-free ambiguity which is formed by the Wide Lane (WL) and Narrow Lane (NL) combinations, the uncombined PPP model is flexible and effective to generate the FCB products. This study presents the FCB estimation method based on the multi-Global Navigation Satellite System (GNSS) precise satellite orbit and clock corrections from the international GNSS Monitoring and Assessment System (iGMAS) observations using the uncombined PPP model. The dual-frequency raw ambiguities are combined by the integer coefficients (4,− 3) and (1,− 1) to directly estimate the FCBs. The details of FCB estimation are described with the Global Positioning System (GPS), BeiDou-2 Navigation Satellite System (BDS-2) and Galileo Navigation Satellite System (Galileo). For the estimated FCBs, the Root Mean Squares (RMSs) of the posterior residuals are smaller than 0.1 cycles, which indicates a high consistency for the float ambiguities. The stability of the WL FCBs series is better than 0.02 cycles for the three GNSS systems, while the STandard Deviation (STD) of the NL FCBs for BDS-2 is larger than 0.139 cycles. The combined FCBs have better stability than the raw series. With the multi-GNSS FCB products, the PPP AR for GPS/BDS-2/Galileo is demonstrated using the raw observations. For hourly static positioning results, the performance of the PPP AR with the three-system observations is improved by 42.6%, but only 13.1% for kinematic positioning results. The results indicate that precise and reliable positioning can be achieved with the PPP AR of GPS/BDS-2/Galileo, supported by multi-GNSS satellite orbit, clock, and FCB products based on iGMAS.

Download Full-text

Exploring the Structural Competition between the Black and the Yellow Phase of CsPbI3

Nanomaterials ◽

10.3390/nano11051282 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1282

Author(s):

Ioannis Deretzis ◽

Corrado Bongiorno ◽

Giovanni Mannino ◽

Emanuele Smecca ◽

Salvatore Sanzaro ◽

...

Keyword(s):

Perovskite Phase ◽

Low Cost ◽

Δ Phase ◽

Nanocrystalline Structures ◽

Halide Perovskites ◽

The Stability ◽

Structural Competition ◽

Lead Halide ◽

Main Candidate ◽

Spontaneous Phase

The realization of stable inorganic perovskites is crucial to enable low-cost solution-processed photovoltaics. However, the main candidate material, CsPbI3, suffers from a spontaneous phase transition at room temperature towards a photo-inactive orthorhombic δ-phase (yellow phase). Here we used theoretical and experimental methods to study the structural and electronic features that determine the stability of the CsPbI3 perovskite. We argued that the two physical characteristics that favor the black perovskite phase at low temperatures are the strong spatial confinement in nanocrystalline structures and the level of electron doping in the material. Within this context, we discussed practical procedures for the realization of long-lasting inorganic lead halide perovskites.

Download Full-text

Longevity of Raw and Lyophilized Crude Urease Extracts

Sustainable Chemistry ◽

10.3390/suschem2020018 ◽

2021 ◽

Vol 2 (2) ◽

pp. 325-334

Author(s):

Neda Javadi ◽

Hamed Khodadadi Tirkolaei ◽

Nasser Hamdan ◽

Edward Kavazanjian

Keyword(s):

Crude Extract ◽

Room Temperature ◽

Low Cost ◽

Extraction Process ◽

Crude Extracts ◽

Simple Extraction ◽

Commercial Applications ◽

Stable Source ◽

The Stability ◽

The Cost

The stability (longevity of activity) of three crude urease extracts was evaluated in a laboratory study as part of an effort to reduce the cost of urease for applications that do not require high purity enzyme. A low-cost, stable source of urease will greatly facilitate engineering applications of urease such as biocementation of soil. Inexpensive crude extracts of urease have been shown to be effective at hydrolyzing urea for carbonate precipitation. However, some studies have suggested that the activity of a crude extract may decrease with time, limiting the potential for its mass production for commercial applications. The stability of crude urease extracts shown to be effective for biocementation was studied. The crude extracts were obtained from jack beans via a simple extraction process, stored at room temperature and at 4 ℃, and periodically tested to evaluate their stability. To facilitate storage and transportation of the extracted enzyme, the longevity of the enzyme following freeze drying (lyophilization) to reduce the crude extract to a powder and subsequent re-hydration into an aqueous solution was evaluated. In an attempt to improve the shelf life of the lyophilized extract, dextran and sucrose were added during lyophilization. The stability of purified commercial urease following rehydration was also investigated. Results of the laboratory tests showed that the lyophilized crude extract maintained its activity during storage more effectively than either the crude extract solution or the rehydrated commercial urease. While incorporating 2% dextran (w/v) prior to lyophilization of the crude extract increased the overall enzymatic activity, it did not enhance the stability of the urease during storage.

Download Full-text

A Real-Time Method for Improving Stability of Monolithic Quartz Crystal Microbalance Operating under Harsh Environmental Conditions

Sensors ◽

10.3390/s21124166 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4166

Author(s):

Román Fernández ◽

María Calero ◽

Yolanda Jiménez ◽

Antonio Arnau

Keyword(s):

Real Time ◽

Quartz Crystal Microbalance ◽

Quartz Crystal ◽

Limit Of Detection ◽

Quartz Substrate ◽

Low Cost ◽

Discrete Wavelet ◽

Reagent Consumption ◽

Measurement Cell ◽

The Stability

Monolithic quartz crystal microbalance (MQCM) has recently emerged as a very promising technology suitable for biosensing applications. These devices consist of an array of miniaturized QCM sensors integrated within the same quartz substrate capable of detecting multiple target analytes simultaneously. Their relevant benefits include high throughput, low cost per sensor unit, low sample/reagent consumption and fast sensing response. Despite the great potential of MQCM, unwanted environmental factors (e.g., temperature, humidity, vibrations, or pressure) and perturbations intrinsic to the sensor setup (e.g., mechanical stress exerted by the measurement cell or electronic noise of the characterization system) can affect sensor stability, masking the signal of interest and degrading the limit of detection (LoD). Here, we present a method based on the discrete wavelet transform (DWT) to improve the stability of the resonance frequency and dissipation signals in real time. The method takes advantage of the similarity among the noise patterns of the resonators integrated in an MQCM device to mitigate disturbing factors that impact on sensor response. Performance of the method is validated by studying the adsorption of proteins (neutravidin and biotinylated albumin) under external controlled factors (temperature and pressure/flow rate) that simulate unwanted disturbances.

Download Full-text

Modal Analyses of Deployable Truss Structures Based on Shape Memory Polymer Composites

International Journal of Applied Mechanics ◽

10.1142/s1758825116400093 ◽

2016 ◽

Vol 08 (07) ◽

pp. 1640009 ◽

Cited By ~ 18

Author(s):

Fengfeng Li ◽

Liwu Liu ◽

Xin Lan ◽

Tong Wang ◽

Xiangyu Li ◽

...

Keyword(s):

Finite Element ◽

Shape Memory ◽

Polymer Composites ◽

Dynamic Properties ◽

Low Cost ◽

Shape Memory Polymer ◽

Truss Structures ◽

Modal Test ◽

The Stability ◽

Mechanical Devices

With large spatial deployable antennas used more widely, the stability of deployable antennas is attracting more attention. The form of the support structure is an important factor of the antenna’s natural frequency, which is essential to study to prevent the resonance. The deployable truss structures based on shape memory polymer composites (SMPCs) have made themselves feasible for their unique properties such as highly reliable, low-cost, light weight, and self-deployment without complex mechanical devices compared with conventional deployable masts. This study offers deliverables as follows: an establishment of three-longeron beam and three-longeron truss finite element models by using ABAQUS; calculation of natural frequencies and vibration modes; parameter studies for influence on their dynamic properties; manufacture of a three-longeron truss based on SMPC, and modal test of the three-longeron truss. The results show that modal test and finite element simulation fit well.

Download Full-text