Robotic control for cognitive UWB radar

In the paper, we describe a trajectory planning problem for a six-DoF robotic manipulator arm that carries an ultra-wideband (UWB) radar sensor with synthetic aperture (SAR). The resolution depends on the trajectory and velocity profile of the sensor head. The constraints can be modeled as an optimization problem to obtain a feasible, collision-free target trajectory of the end-effector of the manipulator arm in Cartesian coordinates that minimizes observation time. For 3D reconstruction, the target is observed in multiple height slices. For through-the-wall radar the sensor can be operated in sliding mode for scanning larger areas. For IED inspection the spotlight mode is preferred, constantly pointing the antennas towards the target to obtain maximum azimuth resolution. UWB sensors typically use a wide spectrum shared by other RF communication systems. This may become a limiting factor on system sensitivity and severely degrade the image quality. Cognitive radars can adapt dynamically their bandwidth, frequency and other transmit parameters to the radio frequency environment to avoid interference with primary users.

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A decorrelating aided partial combining RAKE receiver for direct sequence ultra-wideband communication systems

IET International Conference on Wireless Mobile and Multimedia Networks Proceedings (ICWMMN 2006) ◽

10.1049/cp:20061281 ◽

2006 ◽

Author(s):

Shen-yuan Yang ◽

Qian Yin ◽

Xiao-yan Bi ◽

Zheng Li

Keyword(s):

Communication Systems ◽

Rake Receiver ◽

Ultra Wideband ◽

Direct Sequence ◽

Ultra Wideband Communication

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VOLTAGE CONTROL OF MAGNETISM IN MULTIFERROIC HETEROSTRUCTURES AND DEVICES

SPIN ◽

10.1142/s2010324712400048 ◽

2012 ◽

Vol 02 (03) ◽

pp. 1240004 ◽

Cited By ~ 200

Author(s):

NIAN X. SUN ◽

GOPALAN SRINIVASAN

Keyword(s):

Magnetic Field ◽

Communication Systems ◽

Recent Progress ◽

Phase Shifters ◽

Ultra Wideband ◽

Superior Performance ◽

Microwave Devices ◽

Multiferroic Materials ◽

Multiferroic Heterostructures ◽

Rf Microwave

Multiferroic materials and devices have attracted intensified recent interests due to the demonstrated strong magnetoelectric (ME) coupling in new multiferroic materials and devices with unique functionalities and superior performance characteristics. Strong ME coupling has been demonstrated in a variety of multiferroic heterostructures, including bulk magnetic on ferro/piezoelectric multiferroic heterostructures, magnetic film on ferro/piezoelectric slab multiferroic heterostructures, thin film multiferroic heterostructures, etc. Different multiferroic devices have been demonstrated, which include magnetic sensors, energy harvesters, and voltage tunable multiferroic RF/microwave devices which are compact, lightweight, and power efficient. In this progress report, we cover the most recent progress on multiferroic heterostructures and devices with a focus on voltage tunable multiferroic heterostructures and devices with strong converse ME coupling. Recent progress on magnetic-field tunable RF/microwave devices are also covered, including novel non-reciprocal tunable bandpass filters with ultra wideband isolation, compact, low loss and high power handling phase shifters, etc. These novel tunable multiferroic heterostructures and devices and tunable magnetic devices provide great opportunities for next generation reconfigurable RF/microwave communication systems and radars, Spintronics, magnetic field sensing, etc.

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A Novel Method for Breath Detection via Stepped-Frequency Continuous Wave Ultra-Wideband (SFCW UWB) Radars Based on Operational Bandwidth Segmentation

Sensors ◽

10.3390/s18113873 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3873 ◽

Cited By ~ 3

Author(s):

Hao Lv ◽

Teng Jiao ◽

Yang Zhang ◽

Fulai Liang ◽

Fugui Qi ◽

...

Keyword(s):

Continuous Wave ◽

Doppler Radar ◽

Ultra Wideband ◽

Time Dimension ◽

Processing Scheme ◽

Practical Applications ◽

Uwb Radar ◽

Operational Frequency ◽

Stepped Frequency ◽

Breath Detection

Human being detection via ultra-wideband (UWB) radars has shown great prospects in many areas, such as biomedicine, military operation, public security, emergency rescue, and so on. When a person stays stationary, the main feature that separates him/her from surroundings is the movement of chest wall due to breath. There have been many algorithms developed for breath detection while using UWB radars. However, those algorithms were almost based on a basic scheme that focused on processing in the time dimension of UWB data. They did not utilize the benefits from the wide operational bandwidth of UWB radars to show potential superiority over those narrowband systems such as a continuous wave (CW) Doppler radar. In this paper, a breath detection method was proposed based on operational bandwidth segmentation. A basic theoretical model was firstly introduced, indicating that characteristics of breath signals contained in UWB echoes were consistent among the operational frequencies, while those of clutters were not. So, the method divided a set of UWB echo data into a number of subsets, each of which corresponded to a sub-band within the operational bandwidth of the UWB radar. Thus information about the operational frequency is provided for subsequent processing. With the aid of the information, a breath enhancement algorithm was developed mainly by averaging the segmented UWB data along the operational frequency. The algorithm’s performance was verified by data measured by a stepped-frequency CW (SFCW) UWB radar. The experimental results showed that the algorithm performed better than that without the segmentation. They also showed its feasibility for fast detection of breath based on a short duration of data. Moreover, the method’s potential for target identification and impulse-radio (IR) UWB radar was investigated. In summary, the method provides a new processing scheme for UWB radars when they are used for breath detection. With this scheme, the UWB radars have a benefit of greater flexibility in data processing over those narrowband radars, and thus will perform more effectively and efficiently in practical applications.

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Low-Complexity Synchronization Scheme with Low-Resolution ADCs

Information ◽

10.3390/info9120313 ◽

2018 ◽

Vol 9 (12) ◽

pp. 313 ◽

Cited By ~ 1

Author(s):

Liu Jun ◽

Luo Zhongqiang ◽

Xiong Xingzhong

Keyword(s):

Power Consumption ◽

Communication Systems ◽

Orthogonal Frequency Division Multiplexing ◽

Frequency Offset ◽

Ultra Wideband ◽

Timing Synchronization ◽

Quantization Scheme ◽

Frequency Offset Estimation ◽

Low Resolution ◽

Synchronization Scheme

An important function of next-generation (5G) and beyond mobile communication systems is aim to provide thousand-fold capacity growth and to support high-speed data transmission up to several megabits per second. However, the research community and industries have to face a dilemma of power consumption and hardware design to satisfy the increasing communication requirements. For the purpose of improving the system cost, power consumption, and implementation complexity, a novel scheme of symbol timing and frequency offset estimation with low-resolution analog-to-digital converters (ADCs) based on an orthogonal frequency division multiplexing ultra-wideband (OFDM-UWB) system is proposed in this paper. In our work, we first verified the principle that the autocorrelation of the pseudo-noise (PN) sequences was not affected by low-resolution quantization. With the help of this property, the timing synchronization could be strongly implemented against the influence of low-resolution quantization. Then, the transmitted signal structure and low-resolution quantization scheme under the synchronization scheme were designed. Finally, a frequency offset estimation model with one-bit timing synchronization was established. Theoretical analysis and simulation results corroborate that the performance of the proposed scheme not only approximates to that of the full-resolution synchronization scheme, but also has lower power consumption and computational complexity.

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Kasami Code-Shift-Keying Modulation for Ultra-Wideband Communication Systems

IEEE Transactions on Communications ◽

10.1109/tcomm.2007.892471 ◽

2007 ◽

Vol 55 (3) ◽

pp. 631-631

Keyword(s):

Communication Systems ◽

Ultra Wideband ◽

Shift Keying ◽

Ultra Wideband Communication

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A Multiple Target Positioning and Tracking System Behind Brick-Concrete Walls Using Multiple Monostatic IR-UWB Radars

Sensors ◽

10.3390/s19184033 ◽

2019 ◽

Vol 19 (18) ◽

pp. 4033 ◽

Cited By ~ 1

Author(s):

Yoo ◽

Wang ◽

Seol ◽

Lee ◽

Chung ◽

...

Keyword(s):

False Alarm ◽

False Alarm Rate ◽

Detection Rate ◽

Tracking System ◽

Radar System ◽

Ultra Wideband ◽

Radar Signal ◽

High Detection Rate ◽

Concrete Walls ◽

Uwb Radar

Recognizing and tracking the targets located behind walls through impulse radio ultra-wideband (IR-UWB) radar provides a significant advantage, as the characteristics of the IR-UWB radar signal enable it to penetrate obstacles. In this study, we design a through-wall radar system to estimate and track multiple targets behind a wall. The radar signal received through the wall experiences distortion, such as attenuation and delay, and the characteristics of the wall are estimated to compensate the distance error. In addition, unlike general cases, it is difficult to maintain a high detection rate and low false alarm rate in this through-wall radar application due to the attenuation and distortion caused by the wall. In particular, the generally used delay-and-sum algorithm is significantly affected by the motion of targets and distortion caused by the wall, rendering it difficult to obtain a good performance. Thus, we propose a novel method, which calculates the likelihood that a target exists in a certain location through a detection process. Unlike the delay-and-sum algorithm, this method does not use the radar signal directly. Simulations and experiments are conducted in different cases to show the validity of our through-wall radar system. The results obtained by using the proposed algorithm as well as delay-and-sum and trilateration are compared in terms of the detection rate, false alarm rate, and positioning error.

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Trajectory Planning in UAV Emergency Networks with Potential Underlaying D2D Communication Based on K-means

10.21203/rs.3.rs-144554/v1 ◽

2021 ◽

Author(s):

Shuo Zhang ◽

Shuo Shi ◽

Tianming Feng ◽

Xuemai Gu

Keyword(s):

Trajectory Planning ◽

Communication Systems ◽

High Speed ◽

Large Scale ◽

High Reliability ◽

Base Station ◽

Planning Problem ◽

Communication Signal ◽

User Coverage ◽

Trajectory Length

Abstract Unmanned aerial vehicles (UAVs) have been widely used in communication systems due to excellent maneuverability and mobility. The ultra-high speed, ultra-low latency, and ultra-high reliability of 5th generation wireless systems (5G) have further promoted vigorous development of UAVs. Compared with traditional means of communication, UAV can provide services for ground terminal without time and space constraints, so it is often used as air base station (BS). Especially in emergency communications and rescue, it provides temporary communication signal coverage service for disaster areas. In the face of large-scale and scattered user coverage tasks, UAV's trajectory is an important factor affecting its energy consumption and communication performance. In this paper, we consider a UAV emergency communication network where UAV aims to achieve complete coverage of potential underlying D2D users (DUs). The trajectory planning problem is transformed into the deployment and connection problem of stop points (SPs). Aiming at trajectory length and sum throughput, two trajectory planning algorithms based on K-means are proposed. Due to the non-convexity of sum throughput optimization, we present a sub-optimal solution by using the successive convex approximation (SCA) method. In order to balance the relationship between trajectory length and sum throughput, we propose a joint evaluation index which is used as an objective function to further optimize trajectory. Simulation results show the validity of the proposed algorithms which have advantages over the well-known benchmark scheme in terms of trajectory length and sum throughput.

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Toward the widespread application of low-cost technologies in coastal ocean observing (Internet of Things for the Ocean)

Mediterranean Marine Science ◽

10.12681/mms.25060 ◽

2021 ◽

Author(s):

MARCO MARCELLI ◽

VIVIANA PIERMATTEI ◽

RICCARDO GERIN ◽

FABIO BRUNETTI ◽

ERMANNO PIETROSEMOLI ◽

...

Keyword(s):

Communication Systems ◽

Low Cost ◽

Large Data ◽

Cost Effective ◽

Coastal Ocean ◽

Global Ocean ◽

Limiting Factor ◽

Widespread Application ◽

Development Framework ◽

Ocean Observing

The ability to access user-friendly, low-cost instrumentation remains a limiting factor in coastal ocean observing. The majority of currently available marine observation equipment is difficult to deploy, costly to operate, and requires specific technical skills. Moreover, a harmonized observation program for the world’s coastal waters has not yet been established despite the efforts of the global ocean organizations. Global observational systems are mainly focused on open ocean waters and do not include coastal and shelf areas, where models and satellites require large data sets for their calibration and validation. Fortunately, recent technological advances have created opportunities to improve sensors, platforms, and communications that will enable a step-change in coastal ocean observing, which will be driven by a decreasing cost of the components, the availability of cheap housing, low-cost controller/data loggers based on embedded systems, and low/no subscription costs for LPWAN communication systems. Considering the above necessities and opportunities, POGO’s OpenMODs project identified a series of general needs/requirements to be met in an Open science development framework. In order to satisfy monitoring and research necessities, the sensors to be implemented must be easily interfaced with the data acquisition and transmission system, as well as compliant with accuracy and stability requirements. Here we propose an approach to co-design a cost-effective observing modular instrument architecture based on available low-cost measurement and data transmission technologies, able to be mounted/operated on various platforms. This instrument can fit the needs of a large community that includes scientific research (including those in developing countries), non-scientific stakeholders, and educators.

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Dispersion distortions of wide spectrum signals during their propagation in the Earth ionosphere

Antennas ◽

10.18127/j03209601-202102-12 ◽

2021 ◽

Author(s):

M. M. Ivoylova ◽

A. V. Kashin ◽

V. A. Kozlov

Keyword(s):

Electromagnetic Compatibility ◽

Wide Spectrum ◽

Radio Pulse ◽

Current Trend ◽

Polarization Plane ◽

Leading Edge ◽

Ultrashort Pulses ◽

Ultra Wideband ◽

Engineering Systems ◽

Middle Latitudes

The current trend in the development of radio engineering systems (RES) is to use wide spectrum signals, the application of which provides an increase in the resolution and secrecy of the radar operation, an increase in the speed and volume of transmitted information for communication and telemetry systems. The class of such signals includes ultrashort pulses (USP signals), radio pulses with linear frequency modulation (chirp signals). Also of interest are ultra-wideband (UWB) noise signals (UWBN signals), which have high electromagnetic compatibility, stealth and noise immunity. When designing promising ground-based and space-based RES using wide spectrum signals, an important task is to determine the distortions of their envelope shape and distortions of spectrum, as well as the change in the polarization of the emitted wave when passing through the Earth's ionosphere, since taking these distortions into account will provide conditions for optimal reception. This article presents the numerical assessment results of the expected distortions of the wide spectrum signals main types of the decimeter wavelength range, for middle latitudes at heights from 100 km to 1000 km. The conversion of the emitted pulse into a frequency modulated radio pulse is typical for the USP signal. For a chirp radio pulse with a monotonically increasing frequency, an initial decrease in duration with an increase in amplitude and subsequent stretching in time with further spread is typical (the amplitude change is estimated due to a change in the signal shape without taking into account spread). For a chirp radio pulse with a monotonically falling frequency and a UWBN signal, dispersion distortions manifest themselves as an increase in their duration with a decrease in amplitude. For all signal types under consideration that have passed through the ionosphere, a leading edge lag is observed, the dependences of frequency on time at an altitude of 1000 km are repeated and are close to hyperbolic character, the energy spectra envelope shape of the considered signals is almost not distorted. The polarization plane rotation for signals with a spectrum concentrated in the frequency range above 0.7 GHz does not exceed 45

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