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Article
Publication date: 8 January 2018

Shafinaz Mohd Basir, Idnin Pasya, Tajmalludin Yaakob, Nur Emileen Abd Rashid and Takehiko Kobayashi

This paper aims to present an approach of utilizing multiple-input multiple-output (MIMO) radar concept to enhance pedestrian classification in automotive sensors. In a practical…

Abstract

Purpose

This paper aims to present an approach of utilizing multiple-input multiple-output (MIMO) radar concept to enhance pedestrian classification in automotive sensors. In a practical environment, radar signals reflected from pedestrians and slow-moving vehicles are similar in terms of reflecting angle and Doppler returns, inducing difficulty for target discrimination. An efficient discrimination between the two targets depends on the ability of the sensor to extract unique characteristics from each target, for example, by exploiting Doppler signatures. This study describes the utilization of MIMO radar for Doppler measurement and demonstrates its application to improve pedestrian classification through actual laboratory measurements.

Design/methodology/approach

Multiple non-modulated sinusoidal signals are transmitted orthogonally over a MIMO array using time division scheme, illuminating human and non-human targets. The reflected signal entering each of the receiving antenna are combined at the radar receiver prior to Doppler processing. Doppler histogram was formulated based on a series of measurements, and the Doppler spread of the targets was determined from the histograms. Results were compared between MIMO and conventional single antenna systems.

Findings

Measurement results indicated that the MIMO configuration provides able to capture more Doppler information compared to conventional single antenna systems, enabling a more precise discrimination between pedestrian and other slow-moving objects on the road.

Originality/value

The study demonstrated the effectiveness of using MIMO configuration in radar-based automotive sensor to enhance the accuracy of Doppler estimation, which is seldom highlighted in literature of MIMO radars. The result also indicated its usefulness in improving target discrimination capability of the radar, through actual measurement.

Details

Sensor Review, vol. 38 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 March 2001

Céline Corbrion, Thierry Ditchi, Stephane Holé, Eric Carreel and Jacques Lewiner

On‐board absolute speed sensors would be very useful in automotive applications in order to perform the measurement of the speed independently of the wheel rotation. Narrow beam…

Abstract

On‐board absolute speed sensors would be very useful in automotive applications in order to perform the measurement of the speed independently of the wheel rotation. Narrow beam Doppler sensors give a good accuracy but only operate if there is a reflecting obstacle in the antenna footprint on the road. Broad beam Doppler sensors have the advantage of offering a higher probability of getting a reflected wave, but they require multiple frequencies. A novel sensor is presented. It uses a single frequency emission, which leads to low cost devices. Simulations and measurements have been carried out which show that it is particularly well adapted to high‐risk situations, for instance icy or very wet road surfaces, when only a few reflecting obstacles are present. In such situations, the accuracy of the measurement is typically of the order of 0.5 per cent.

Details

Sensor Review, vol. 21 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 April 1990

Viv Hughes and Jon Sawyer

The problem of fast and accurate positioning relative to the sea floor can be solved using the Doppler shift of high frequency acoustic signals.

Abstract

The problem of fast and accurate positioning relative to the sea floor can be solved using the Doppler shift of high frequency acoustic signals.

Details

Sensor Review, vol. 10 no. 4
Type: Research Article
ISSN: 0260-2288

Article
Publication date: 1 March 1997

P.I.J. Keeton and F.S. Schlindwein

Provides an introduction into wavelets and illustrates their application with two examples. The wavelet transform provides the analyst with a scaleable time‐frequency…

1028

Abstract

Provides an introduction into wavelets and illustrates their application with two examples. The wavelet transform provides the analyst with a scaleable time‐frequency representation of the signal, which may uncover details not evidenced by conventional signal processing techniques. The signals used in this paper are Doppler ultrasound recordings of blood flow velocity taken from the internal carotid artery and the femoral artery. Shows how wavelets can be used as an alternative signal processing tool to the short time Fourier transform for the extraction of the time‐frequency distribution of Doppler ultrasound signals. Implements wavelet‐based adaptive filtering for the extraction of maximum blood velocity envelopes in the post processing of Doppler signals.

Details

Sensor Review, vol. 17 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 January 1974

THE COHERENT PULSE DOPPLER RADAR ALTIMETER developed by Hoffman Electronics Corporation, operates with only a single antenna, the highly reliable, solid‐state altimeter set…

Abstract

THE COHERENT PULSE DOPPLER RADAR ALTIMETER developed by Hoffman Electronics Corporation, operates with only a single antenna, the highly reliable, solid‐state altimeter set, electronic AN/APN‐201, fig 1, provides pilots with precise altitudes down to ground zero without fear of false lock or double bounce readings.

Details

Aircraft Engineering and Aerospace Technology, vol. 46 no. 1
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 August 2002

Ch. Hajiyev and O. Akgun

In this study, Integrated Air Data – Doppler Navigation System is developed and presented. Air Data System and Doppler Radar have different advantages and disadvantages in…

Abstract

In this study, Integrated Air Data – Doppler Navigation System is developed and presented. Air Data System and Doppler Radar have different advantages and disadvantages in applications in flight control and navigation systems. The reason of this integration is to achieve the best combination of the features and eliminate the disadvantages of these systems. As a consequence of this integration via Kalman filtering, an integrated navigation system with high accuracy of airvehicle velocity and position and with high measurement frequency is attained. On basis of this integrated system, the possibility to estimate accurate and real time inflight wind speed is explained.

Details

Aircraft Engineering and Aerospace Technology, vol. 74 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 7 August 2017

Weiwei Pan and Dongsheng Wang

Flow measurement plays an important role in modern industrial production. Flow measurement methods based on optical fiber systems have become a main research focus.

Abstract

Purpose

Flow measurement plays an important role in modern industrial production. Flow measurement methods based on optical fiber systems have become a main research focus.

Design/methodology/approach

Applying flow measurement theory and the structural characteristics of optical fiber, flow measurement of paste can be achieved through a combined laser Doppler and optical fiber sensing system based on the principle of optical fiber grating sensors and flow sensors. The system is developed to include light selection, photoelectric detection, a voltage amplifier circuit and a signal filtering circuit.

Findings

The system is shown, through a comparative experiment, to be of higher accuracy than the traditional ultrasonic method.

Originality/value

A new method for measuring the paste flow is presented, which is based on the principle of optical fiber Doppler. The method has the advantages of convenient installation, high accuracy and low cost. Experiments show that the method is feasible.

Details

World Journal of Engineering, vol. 14 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 February 1978

Terence Ford, C. Eng and AFRAeS

The need to provide precision approach guidance over wider angular coverage than is possible with the present Instrument Landing System (ILS) and the wish to avoid siting problems…

Abstract

The need to provide precision approach guidance over wider angular coverage than is possible with the present Instrument Landing System (ILS) and the wish to avoid siting problems sometimes encountered with the current equipment has prompted work on new systems in various countries. Using existing technology, independence of site conditions can, to a large extent, be achieved by the employment of microwave frequencies.

Details

Aircraft Engineering and Aerospace Technology, vol. 50 no. 2
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 1964

J.A. Lee

THE simplest concept of inertial navigation is that of using an accelerometcr for measurement of vehicle acceleration, integrating once to give a measure of velocity and twice to…

Abstract

THE simplest concept of inertial navigation is that of using an accelerometcr for measurement of vehicle acceleration, integrating once to give a measure of velocity and twice to give a measure of distance travelled (fig. 1). For this purpose, the direction of the input axis of the accelerometcr must be kept constant, or alternatively its direction at all times must be known and its changing direction must be taken into account in interpreting its output. In either case, provision of a stable attitude reference is necessary. Gyroscopes can provide this feature.

Details

Aircraft Engineering and Aerospace Technology, vol. 36 no. 1
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 7 July 2022

Jintian Hu, Jin Liu, Yidi Wang and Xiaolin Ning

This study aims to address the problem of the divergence of traditional inertial navigation system (INS)/celestial navigation system (CNS)-integrated navigation for ballistic…

Abstract

Purpose

This study aims to address the problem of the divergence of traditional inertial navigation system (INS)/celestial navigation system (CNS)-integrated navigation for ballistic missiles. The authors introduce Doppler navigation system (DNS) and X-ray pulsar navigation (XNAV) to the traditional INS/CNS-integrated navigation system and then propose an INS/CNS/DNS/XNAV deep integrated navigation system.

Design/methodology/approach

DNS and XNAV can provide velocity and position information, respectively. In addition to providing velocity information directly, DNS suppresses the impact of the Doppler effect on pulsar time of arrival (TOA). A pulsar TOA with drift bias is observed during the short navigation process. To solve this problem, the pulsar TOA drift bias model is established. And the parameters of the navigation filter are optimised based on this model.

Findings

The experimental results show that the INS/CNS/DNS/XNAV deep integrated navigation can suppress the drift of the accelerometer to a certain extent to improve the precision of position and velocity determination. In addition, this integrated navigation method can reduce the required accuracy of inertial navigation, thereby reducing the cost of missile manufacturing and realising low-cost and high-precision navigation.

Originality/value

The velocity information provided by the DNS can suppress the pulsar TOA drift, thereby improving the positioning accuracy of the XNAV. This reflects the “deep” integration of these two navigation methods.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

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