27 research outputs found
Structural Antennas for 3cm Radar Onboard Multi-Rotor UAV
A series of 3cm amateur band radar antennas suitable for installation on a cinematic grade multi-rotor UAV were considered. A wideband open waveguide mouth antenna was developed that can be made from the existing arms of a multi-rotor UAV without any increase in weight for side-looking wall detection ranging radar. For downward looking radio altimeter, cutting slots in the arms to form slotted waveguide antennas was shown in simulation to be possible both in terms of covering the entire 3cm band from 10 to 10.5GHz and without overly weakening the arms as structural members
FMCW rail-mounted SAR: Porting spotlight SAR imaging from MATLAB to FPGA
In this work, a low-cost laptop-based radar platform derived from the MIT open courseware has been implemented. It can perform ranging, Doppler measurement and SAR imaging using MATLAB as the processor. In this work, porting the signal processing algorithms onto a FPGA platform will be addressed as well as differences between results obtained using MATLAB and those obtained using the FPGA platform. The target FPGA platforms were a Virtex6 DSP kit and Spartan3A starter kit, the latter was also low-cost to further reduce the cost for students to access radar technology
Porting Spotlight Range Migration Algorithm Processor from Matlab to Virtex 6
This paper describes the implementation and optimization of a Synthetic Aperture Radar process Spotlight Range Migration Algorithm processor on FPGA Virtex 6 DSP kit that fits on the chip. The mean/max error compared to a software implementation is -54/-28.74dB for 55 elements and 882 samples
Empirical Comparison of Chirp and Multitones on Experimental UWB Software Defined Radar Prototype
This paper proposes and tests an approach for an unbiased study of radar waveforms' performances. Using the ultrawide band software defined radar prototype, the performances of Chirp and Multitones are compared in range profile and detection range. The architecture was implemented and has performances comparable to the state of the art in software defined radar prototypes. The experimental results are consistent with the simulations
Scan Performance of Small Spherical Retro-Reflectors
A number of historical small spherical lens retroreflectors were simulated in a commercially available antenna simulator. This 1dBm 2 class retro-reflectors had radii of 2 free space wavelengths, allowing the use of a minimal number of layers to approximate the theoretical Luneburg profile. It was found that further simplification to a 2-layer lens or a single custom material lens were practical. In both cases, RCS of 1.5dBm 2 were achieved with 3dB scan ranges of 110° in simulation
Radar High Resolution Range & Micro-Doppler Analysis of Human Motions
In radar imaging it is well known that relative motion or deformation of parts of illuminated objects induce additional features in the Doppler frequency spectra. These features are called micro-Doppler effect and appear as sidebands around the central Doppler frequency. They can provide valuable information about the structure of the moving parts and may be used for identification purposes [1]. Previous papers have mostly focused on ID micro-Doppler analysis [2-4]. In this paper, we propose to emphasize the analysis of such "non stationary targets" using a 2D imaging space, using both the micro-Doppler and a high range resolution analysis. As in 2D-ISAR imaging, range separation enables us to better discriminate the various effects caused by the time varying reflectors. We will focus our study on human motion. We will see how micro-Doppler signature can be used to extract information on pedestrians gait. We will show examples on simulated and experimental data
Empirical Performance Analysis of Linear Frequency Modulated Pulse and Multitones on UWB Software Defined Radar Prototype
In this study, we apply a protocol for an unbiased analysis of radar signals' performances. Using an experimental UWB software-defined radar, range profile, Doppler profile and detection range are evaluated for both Liner Frequency Modulated pulse and Multitones. The radar was prototyped and is comparable in overall performance to software defined radar test-beds found in the literature. The measured performances are in agreement with the simulations
Gait Analysis of Horses for Lameness Detection with Radar Sensors
This paper presents the preliminary investigation of the use of
radar signatures to detect and assess lameness of horses and its
severity. Radar sensors in this context can provide attractive
contactless sensing capabilities, as a complementary or
alternative technology to the current techniques for lameness
assessment using video-graphics and inertial sensors attached to the horses' body. The paper presents several examples of experimental data collected at the Weipers Centre Equine
Hospital at the University of Glasgow, showing the micro-
Doppler signatures of horses and preliminary results of their
analysis
Empirical Comparison of Chirp and Multitones on Experimental UWB Software Defined Radar Prototype
This paper proposes and tests an approach for an unbiased study of radar waveforms' performances. Using the ultrawide band software defined radar prototype, the performances of Chirp and Multitones are compared in range profile and detection range. The architecture was implemented and has performances comparable to the state of the art in software defined radar prototypes. The experimental results are consistent with the simulations
Activities Recognition and Fall Detection in Continuous Data Streams Using Radar Sensor
This student paper presents a Quadratic-kernel Support Vector Machine (SVM) based FMCW (Frequency Modulated Continuous Wave) radar system to recognize daily activities and detect fall accidents. Data collected in this work is divided into two different collection modes, namely, snapshots mode (different activities individually collected in isolation) and continuous activity mode (continuous streams of activities collected one after the other). For the continuous activity streams, a sliding window approach with 4s duration and 70% overlapping has achieved 84.7% classification accuracy and subsequent improvement of 2.6% has been proved by using Sequential Forward Selection (SFS) on six participants to identify an optimal feature set. A ‘tracking’ graph has been utilized to verify that the radar system can correctly identify falls as critical events among the other activities