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24 GHz radar sensors for automotive applications
Abstract
Automotive radar systems using integrated 24 GHz radar sensor
techniques are currently under development (see Klotz, M. and Rohling,
H., 5th International Conference on Radar Systems, 1999). This paper
describes a radar network consisting of four sensors distributed behind
the front bumper of an experimental car. Each single sensor measures the
target range with high accuracy. A multilateration technique is used in
the radar network for precise azimuth angle estimation even in
multiple-target situations. The system performance is shown in real
traffic situations for parking aid, stop-and-go and blind spot
applications
... A bipolar phase shift keying waveform was used to calculate the Doppler frequency at the selected ranges. In 2000, 24 GHz radars were introduced in parking aid, blind spot detection, and pre-crash detection applications [3]. Four transmitters, receivers, and digital signal processor were used in the pre-crash detection application working in pulsed radar mode. ...
... The received echo is frequency down converted and an ordinary envelope detector receiver was used to detect the echo signal. After that a CFAR is applied to the echo to take decision if the echo is reflected from target or is just a noise [3]. ...
... At this time, there was no restrictions on using the 24 GHz in these applications and working in this band granted a good performance in range and azimuth angle measurements [3]. Nowadays, the 77 GHz radars are preferred because of the following reasons: the 24 GHz was a temporary band (at least in Europe), 24 GHz frequency is reserved for other applications like ISM (industrial scientific and medical) applications, 24 GHz bandwidth limitations and bad range resolution for some applications, and the available higher bandwidth offers better range resolution, and better velocity resolution. ...
Abstract— In this paper, a novel algorithm is presented for moving vehicles detection using
77 GHz automotive radars. Unlike previous methods, that use FFT estimators with CFAR based
threshold detection to detect moving and fixed targets, we use the CFAR method combined with
an adjustable coefficient based on the FFT algorithm output moments. It is found that, low
false alarm rates are achieved using the proposed method. Furthermore, the proposed method is
insensitive to the data window size in time domain as well as its low complexity relative to other
methods.
... They are mostly used in detection of blind spots, cut-in and stop-go scenarios, pre-crash detection, and parking aids [3]. high-frequency module, the latest 3 rd generation LRR3 sensor is not only used in high end vehicle models but is also being featured more and more in medium and compact class cars. ...
... But it should not be seen as a replacement/substitute of LRR system. The SRR has high detection update rates which make it well suited for pre-crash detection and blind spot detection surveillance and warning for rear end collision [3]. and a weight less than 300g. ...
... and transmits detected target object information on the Controller Area Network (CAN) bus to the Radar Decision Unit (RDU). The RDU get the target information from all possible radar sensors in the system and performs the multilateration to get the position and velocity of the tracked target objects[3]. ...
... The advancement of autonomous driving vehicles and the mandatory implementation of autonomous emergency braking systems (AEBSs) in various countries have increased the demand for automotive radar systems that offer increased robustness to adverse weather and variable lighting conditions while providing long-range and accurate measurements [1][2][3][4]. In addition to their application to AEBSs, automotive radar systems can be used in various safety applications, such as forward collision-avoidance assist (FCA), adaptive cruise control (ACC), rear cross-traffic alert, and blind spot detection systems [5,6]. Unlike other sensors-such as cameras and lidar-used in autonomous driving systems, reliable radar systems that can better withstand weather conditions such as sunlight and fog and provide accurate measurements underlie the continued advancement of autonomous driving technology, thereby expanding the scope of applications of radar technology in autonomous vehicles. ...
... Random sample consensus (RANSAC): The speed of the ego-vehicle was matched by distinguishing stationary objects using the RANSAC algorithm and interpreting the radial velocity errors associated with these stationary objects [22]. 6. ...
The development of autonomous driving vehicles has increased the global demand for robust and efficient automotive radar systems. This study proposes an automotive radar-based ego-vehicle speed detection network (AVSD Net) model using convolutional neural networks for estimating the speed of the ego vehicle. The preprocessing and postprocessing methods used for vehicle speed correction are presented in detail. The AVSD Net model exhibits characteristics that are independent of the angular performance of the radar system and its mounting angle on the vehicle, thereby reducing the loss of the maximum detection range without requiring a downward or wide beam for the elevation angle. The ego-vehicle speed is effectively estimated when the range–velocity spectrum data are input into the model. Moreover, preprocessing and postprocessing facilitate an accurate correction of the ego-vehicle speed while reducing the complexity of the model, enabling its application to embedded systems. The proposed ego-vehicle speed correction method can improve safety in various applications, such as autonomous emergency braking systems, forward collision avoidance assist, adaptive cruise control, rear cross-traffic alert, and blind spot detection systems.
... Front-attached radar sensors may be used for front traffic alert (FCTA) as well as to detect objects in the near surroundings of the car. Although the technical development of radar sensors shifts to higher frequency bands (77 GHz and 79 GHz) due to smaller antenna layouts and higher bandwidths, the usage of 24 GHz still has some advantages like less sensitivity to installations conditions and cheaper sensor technology [1]. By considering highly automated driving (HAD) the vehicle itself has to adapt to the environment, i.e. the more information is available to the car the better it may be aware of its surroundings and occurring events. ...
... However, in this paper we will focus on the first issue, what kind of landmarks may be detected with these series radar sensors. 1 0°defines the normal to the sensor. ...
This paper describes the possibilities of automotive series production short range radar sensors in a vehicle environment for Highly Automated Driving. Four 24GHz sensors in our test vehicle provide measurements for an occupancy grid based environmental perception approach. Two example scenarios show the usage of the short range radar data for landmark detection and for free space estimation in construction zones.
... As a second approach, the sensor configuration for u shall consist of only gyros with the real angular rates , which in turn are the sum of the measurement vector and the bias vector x . In this case the state vector x consists of q and x , the input u is equal to , while Equations (8) and (12) lead to: ...
... Therefore, the sensor indexes ι and κ are set to ι = {1, 2} and κ = {3, 4}. 4. Selection of a suitable sensor arrangement to measure y Also according to the number of degrees of freedom, three aiding variables can be sufficient to determine the position and shape of the pendulum. Suitable geometrical values are for example distances to a nearby vertical wall as depicted in Figure 3. Potential sensors to determine such spans are short range radar units [12]. Thus, the aiding vector is: ...
During the last years integrated navigation systems based on gyros,accelerometers, and satellite navigation receivers became powerful,favourably priced devices for the guidance of aircraft and ships.Comparable equipment using especially wheel sensors exists for cars. Thekernel of such systems is a Kalman filter estimating the relevantvehicle motion. The filter design in turn requires a kinematical modelto settle on the motion components considered and to describe themechanical meaning of the measurements employed. Up to now, usual modelsrepresent a single rigid body with two, three or six degrees of freedom.
The assumption of a solitary rigid body reflects mainly classicalnavigation requirements, it is not a consequence of the basic concept ofintegrated navigation systems. In principle, determining the motion ofmechanical systems with other or with additional degrees of freedom ispossible if appropriate kinematical models and suitable sensorarrangements are available.
Based on the theory of integrated navigation systems, the paperdescribes the fundamentals of the design of integrated motionmeasurement systems for multibody structures. The approach isfurthermore illustrated by the example of a double pendulum with amovable inertial support and equipped with microelectromechanical gyrosand accelerometers as well as with radar units. The attachment of thesensors demonstrates that a measurement system layout does typically notrequire considerable modifications of already existing mechanicalassemblies. The performance of the integrated system for the pendulum isdemonstrated by means of simulated and of experimental sensor signals.
... Vehicular radars have several advantages over competing sensor technologies. For example, although considerable progress has been made on improving light detection and ranging (LIDAR) sensors, they are still expensive relative to vehicular radar and exhibit sensitivity issues in low-visibility conditions [1], [2], ultrasonic sensors have limited range and suffer from degraded performance in several common environments [3], [4], and dedicated short range communication (DSRC) networks (which can be used to exchange GPS-based location and velocity information) only work when the colliding vehicle has a radio [5]. Despite their importance in vehicle safety, existing forward vehicular radar products have several limitations. ...
Increasing safety and automation in transportation systems has led to the proliferation of radar and IEEE 802.11 dedicated short range communication (DSRC) in vehicles. Current implementations of vehicular radar devices, however, are expensive, use a substantial amount of bandwidth, and are susceptible to multiple security risks. Consider the feasibility of using an IEEE 802.11 orthogonal frequency division multiplexing (OFDM) communications waveform to perform radar functions. In this paper, we present an approach that determines the mean-normalized channel energy from frequency domain channel estimates and models it as a direct sinusoidal function of target range, enabling closest target range estimation. In addition, we propose an alternative to vehicular forward collision detection by extending IEEE 802.11 dedicated short-range communications (DSRC) and WiFi technology to radar, providing a foundation for joint communications and radar framework. Furthermore, we perform an experimental demonstration using existing IEEE 802.11 devices with minimal modification through algorithm processing on frequency-domain channel estimates. The results of this paper show that our solution delivers similar accuracy and reliability to mmWave radar devices with as little as 20 MHz of spectrum (doubling DSRC's 10 MHz allocation), indicating significant potential for industrial devices with joint vehicular communications and radar capabilities.
... Based on the different installation equipment utilized, the vehicle blind spot detection system can be divided into the radar-based system, ultrasonic-based system, and camerabased system. The radar-based system will generate false alarms in the presence of guardrails or tunnel walls, with low lateral accuracy and difficulties in detecting small objects (such as pedestrians) [1]. Although the cost of the ultrasound-based system is relatively low, the detection range is small and there is a high delay [2]. ...
As an essential part of modern smart manufacturing, road transport with large and heavy trucks has in-creased dramatically. Due to the inside wheel difference in the process of turning, there is a considerable safety hazard in the blind area of the inside wheel difference. In this paper, multiple cameras combined with deep learning algorithms are introduced to detect pedestrians in the blind area of wheel error. A scheme of vehicle-pedestrian safety alarm detection system is developed via the integration of YOLOv5 and an improved binocular distance measurement method. The system accurately measures the distance between the truck and nearby pedestrians by utilizing multiple cameras and PP Human recognition, providing real-time safety alerts. The experimental results show that this method significantly reduces distance measurement errors, improves the reliability of pedestrian detection, achieves high accuracy and real-time performance, and thus enhances the safety of trucks in complex traffic environments.
... The 24 GHz millimeterwave radar is typically used for short-range perception, such as detecting surrounding obstacles and vehicles in parking assistance systems. They can provide coarse perception of the vehicle's surrounding environment, as well as key safety functions for autonomous driving, such as automatic emergency braking and collision avoidance [7]. The 77 GHz millimeter-wave radar, with its higher resolution and sensitivity, is suitable for longer-range perception and finer target identification. ...
For time division multiplexing multiple input multiple output (TDM MIMO) millimeter wave radar, the measurement of target range, velocity and other parameters depends on the phase of the received Intermediate Frequency (IF) signal. The coupling between range and velocity phases occurs when measuring moving targets, leading to inevitable errors in calculating range and velocity from the phase, which in turn affects measurement accuracy. Traditional two-dimensional fast fourier transform (2D FFT) estimation errors are particularly pronounced at high velocity, significantly impacting measurement accuracy. Additionally, due to limitations imposed by the Nyquist sampling theorem, there is a restricted range for velocity measurements that can result in aliasing. In this study, we propose a method to address the coupling of range and velocity based on the original signal as well as a method for velocity compensation to resolve aliasing issues. Our research findings demonstrate that this approach effectively reduces errors in measuring ranges and velocities of high-velocity moving targets while efficiently de-aliasing velocities.
... The technology realisation is increasingly relying on continuously tunable liquid crystals (LC) [7][8][9] based mm-Wave beam steering flat-panel [10] antennas array (static and fault-tolerant), in place of the conventional parabolic dishes [11] with a mechanically rotating mechanism (bulky and maintenance-intensive). The recent decade has witnessed a significant boost in long-range automotive radars at 76-81 GHz [12] with a threefold increase in resolutions than the traditional 24 GHz ones [13], though costs reduction remains challenging for a wider commercialisation. As an enabler for amplitude and phase control of mm-Wave signals, LC-based phase-shifting solution has been on industrial and academic research's radar as one of the cost-effective answers for such high-accuracy-oriented beam-steering applications. ...
Unconventional folded shielded coplanar waveguide (FS-CPW) has yet to be fully investigated for tunable dielectrics-based applications. This work formulates designs of FS-CPW based on liquid crystals (LC) for electrically controlled 0-360˚ phase shifters, featuring a minimally redundant approach for reducing the LC volume and hence the costs for mass production. The design exhibits a few conceptual features that make it stand apart from others, noteworthy, the dual-strip structure with a simplified enclosure engraved that enables LC volume sharing between adjacent core lines. Insertion loss reduction by 0.77 dB and LC volume reduction by 1.62% per device are reported at 77 GHz, as compared with those of the conventional single-strip configuration. Based on the proof-of-concept results obtained for the novel dual-strip FS-CPW proposed, this work provides a springboard for follow-up investible propositions that will underpin the development of a phased array demonstrator.
... Together with other sensors like lidar, optical camera and ultrasound, automotive radar collects a wealth of information on the surrounding environment in multiple dimensions including range, Doppler and angle, which builds the cornerstone of autonomous driving. The automobile industry is quite familiar with radar technique, e.g., the automobile manufacturers have been using radar on parking assistance system for decades [4]. ...
The time division multiple access (TDMA) technique has been applied in automotive multiple-input multiple-output (MIMO) radar. However, it suffers from the transmit energy loss, and as a result the parameter estimation performance degradation when the number of transmit elements increases. To tackle these problem, a transmit beamspace (TB) Doppler division multiple access (DDMA) approach is proposed. First, a phase modulation matrix with empty Doppler spectrum is introduced. By exploiting the empty Doppler spectrum, a test function based on sequential detection is developed to mitigate the Doppler ambiguity in DDMA waveform. Then, a discrete Fourier transform (DFT)-based TB in slow-time is formed.The proposed method can achieve waveform diversity in Doppler domain and generate a TB in slow-time that concentrates the transmitted power in a fixed spatial region to improve the transmit energy distribution for automotive MIMO radar, which is favored by medium/long range radar (MRR/LRR) applications. As compared to the conventional TDMA technique, the proposed TB DDMA approach can fully exploit the transmission capabilities of all transmit elements to ensure that the emitted power is efficiently used and inherits easy implementation. Moreover, the proposed TB DDMA method avoids the trade-off between the active time for each transmit antenna and the frame time. Simulation results verify the effectiveness of the proposed TB DDMA approach for automotive MIMO radar.
... Two frequency bands, 24 GHz and 77 GHz, have been predominantly exploited for automotive radars [30][31][32]. The 24-GHz band is mainly used for short-range radar systems with a detection range up to 30 m [30,33], while the 77-GHz band is mainly used for long-range radar systems with a detection range up to 250 m [31]. A frequency modulated continuous wave (FMCW) radar is the most common type of automotive radars used for remote sensing of surroundings [31]. ...
Driving environment perception for automated vehicles is typically achieved by the use of automotive remote sensors such as radars and cameras. A vehicular wireless communication system can be viewed as a new type of remote sensor that plays a central role in connected and automated vehicles (CAVs), which are capable of sharing information with each other and also with the surrounding infrastructure. In this paper, we present the design and implementation of driving environment perception based on the fusion of vehicular wireless communications and automotive remote sensors. A track-to-track fusion of high-level sensor data and vehicular wireless communication data was performed to accurately and reliably locate the remote target in the vehicle surroundings and predict the future trajectory. The proposed approach was implemented and evaluated in vehicle tests conducted at a proving ground. The experimental results demonstrate that using vehicular wireless communications in conjunction with the on-board sensors enables improved perception of the surrounding vehicle located at varying longitudinal and lateral distances. The results also indicate that vehicle future trajectory and potential crash involvement can be reliably predicted with the proposed system in different cut-in driving scenarios.
... However, those technical developments still raise two main problems. First, the vehicle assistance systems only function within the field of vision of the sensor systems [2,3]. Second, the resulting solutions to network vehicles with each other and the infrastructure, making the detection of hazards even before the direct line of sight possible, has up to now been limited exclusively to motorized traffic [4,5,6]. ...
... Cars utilizing SRR sensors are equipped with at least 4 radar sensors, connected to a central radar control unit [24]. This control unit fuses the data from all the SRR sensors to improve the target list of the surrounding environment. ...
Agricultural robots use various sensors for localization and mapping on the fields. These sensors vary from global navigation sensors providing absolute position to vision and laser which provide relative localization with respect to the environment. The same type of sensors are also in use in autonomous cars as well as new generation manual driven cars. However, these sensors suffer in bad weather conditions like rain and fog. In order to eliminate weather related problems the automotive industry has been working on radar technology, and finally they have been able to improve the technology and miniaturize for use in commercial cars. In this paper, we evaluate the performance of an automotive short range radar sensor in an orchard, showing that leading edge automotive technology can help improve localization and mapping capabilities of agricultural robots allowing them to work autonomously even in foggy weather.
... For additional features, filters for automotives are designed at 24GHz since 2012.These improved designs provides easy and accurate detection of target in automotives, estimation of azimuth angle for multiple target situations. These shows that addition of modern digital hardware extends the parameters like size, updating rate, performance etc. [6][7].Further, a design comprising of shunt ring resonator and a shunt stepped impedance open circuit stubs fixed at the mid of parallel coupled lines are fabricated for low loss, small size and high selectivity [8].But, the insertion loss is about 3.7dB and return loss of 12dB with comparatively lower fractional BW of 22%. ...
This paper incorporates an improved design of Ultra Wideband Bandpass filter by using split ring resonators (SRR) along with the coupled microstrip lines. The use of split ring resonators and shunt step impedance open circuit stub enhances the stability due to transmission zeroes at the ends. The designing of filter and simulation of parameters is carried out using Ansoft’s HFSS 13.0 software on RT/Duroid 6002 as a substrate with dielectric constant of 2.94. The design utilizes a frequency band from 22GHz to 29GHz. This band is reserved for Automotive Radar system and sensors as per FCC specifications. The proposed design demonstrates insertion loss less than 0.6dB and return loss better than 12dB at mid frequency i.e. 24.4GHz. The reflection coefficient shows high stability of about 12.47dB at mid frequency. The fractional bandwidth of the proposed filter is about 28.7% and size of filter design is small due to thickness of 0.127mm.
... Vehicular radars have several advantages over competing sensor technologies. For example, light detection and ranging (LIDAR) sensors are expensive and are sensitive to low-visibility conditions [1], [2], ultrasonic sensors have limited range and suffer from degraded performance in several common environments [3], and dedicated short range communication (DSRC) networks (which can be used to exchange GPS-based location and velocity information) only work when the colliding vehicle has a radio [4]. ...
Increasing safety and automation in transportation systems has led to the proliferation of radar and IEEE 802.11 dedicated short range communication (DSRC) in vehicles. Current implementations of vehicular radar devices, however, are expensive, use a substantial amount of bandwidth, and are susceptible to multiple security risks. Consider the feasibility of using an IEEE 802.11 orthogonal frequency division multiplexing (OFDM) communications waveform to perform radar functions. In this paper, we present an approach that determines the mean-normalized channel energy from frequency domain channel estimates and models it as a direct sinusoidal function of target range, enabling closest target range estimation. In addition, we propose an alternative to vehicular forward collision detection by extending IEEE 802.11 dedicated short-range communications (DSRC) and WiFi technology to radar, providing a foundation for joint communications and radar framework. Furthermore, we perform an experimental demonstration using existing IEEE 802.11 devices with minimal modification through algorithm processing on frequency-domain channel estimates. The results of this paper show that our solution delivers similar accuracy and reliability to mmWave radar devices with as little as 20 MHz of spectrum (doubling DSRC's 10 MHz allocation), indicating significant potential for industrial devices with joint vehicular communications and radar capabilities.
... cameras) which detect various road markings such as for lanes, edges of the road, road works, etc. [28], [29]. However, short range or long range radar can also be used to detect the environment around the vehicle and has a higher accuracy for measurements [24], [30], [31]. Other technologies employed include inertial sensors, GNSS and V2V (vehicle to vehicle) communication [21]. ...
This paper presents the results of a study on road infrastructure requirements in the context of increased use of highly automated vehicles. An investigation of the interplay between road infrastructure and automated vehicles was performed, with the aim of defining requirements for future road design and planning towards safe and efficient road traffic. Based on a comprehensive review of literature, three subgroups of automated driving systems have been selected for further analysis, which differ in their purpose of use, technologies applied and market readiness: 1) Lane assistance, 2) Collision avoidance and 3) Speed control systems. Results from an online expert survey conducted for this work indicate that the main challenges for the introduction of highly automated vehicles are complex urban environments, temporary work zones and poor visibility due to bad weather condition. Following a list of requirements for road engineering derived from those results, the paper is concluded with a discussion about future needs for amendments in road planning and design regulations.
... The priority is set on the basis of conflict risk. By sharing the reliable and fast exchange of real-time and safety-relevant data between vehicles, the range of awareness of the vehicle and its driver can be increased significantly compared to systems that are using unilateral perception of the radar sensors and video sensors [3]. ...
... Moreover, continuous-wave operation makes FMCW radars less complex, thus cheaper and more reliable than pulse radars. These properties have caused the widespread use of FMCW radar technology for example in automotive applications [3]. Similarly, in rain radar and industry K-band, FMCW has many significant applications [4,5]. ...
This paper investigates the channel characterization of Rayleigh fading channel using K-band frequency-modulated continuous wave (FMCW) radar system. An IF (intermediate frequency) signal of K-band FMCW radar can be treated as time and frequency domain signals due to a unique property of linear frequency modulation (LFM). First, channel sounder FMCW radar stability has been confirmed by measuring power flatness of transmitted radio frequency signal and estimated range in anechoic chamber before conducting the experiment for channel characterization of Rayleigh fading channel. Next, the measurement setup has been conducted in reverberation chamber which emulates multipath fading phenomena. In reverberation chamber, four different cases have been examined by changing the boundary conditions inside it with and without flat microwave absorbers. This investigation leads to obtained scattered plots, normalized propagation delay profiles (PDPs), mean excess delay, root-mean-square (RMS) delay spread and envelope distribution of Rayleigh fading channel at about 24.591 GHz.
... When planning a sensor network to contribute to the mentioned applications, several questions rise and will be discussed in the following chapters. Publications on short range radar networks can be found in [KLO99], [KLO00] and [MEN00]. ...
... In the last two decades magnetoresistive sensors have attracted great interest from the science and technology point of view. Some authors use the acronym XMR [27,28] to refer to all technologies arising for implementing MR sensors: AMR, GMR and TMR. ...
Fractional calculus is considered when derivatives and integrals of non-integer order are applied over a specific function. In the electrical and electronic domain, the transfer function dependence of a fractional filter not only by the filter order n, but additionally, of the fractional order α is an example of a great number of systems where its input-output behavior could be more exactly modeled by a fractional behavior. Following this aim, the present work shows the experimental ac large-signal frequency response of a family of electrical current sensors based in different spintronic conduction mechanisms. Using an ac characterization set-up the sensor transimpedance function Zt(if) is obtained considering it as the relationship between sensor output voltage and input sensing current,
Zt(jf)=Vo,sensor(jf)/Isensor(jf). The study has been extended to various magnetoresistance sensors based in different technologies like anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), spin-valve (GMR-SV) and tunnel magnetoresistance (TMR). The resulting modeling shows two predominant behaviors, the low-pass and the inverse low-pass with fractional index different from the classical integer response. The TMR technology with internal magnetization offers the best dynamic and sensitivity properties opening the way to develop actual industrial applications.
... Vehicle equipped by the UWB radar sensors uses directional antennas with the center frequency range from 24,00 to 24,25GHz, which is a compromise between: unit size, cost per unit, required bandwidth, application capability and mass production orientation [6]. Higher frequencies are not suitable at the time especially because of bad repeatability of units. ...
Ultra-wideband (UWB) devices are able to transmit data over a wide spectrum of frequency bands at very low power. Radio technologies are very sensitive to spectrum sharing due to the interference of signals. The sensitivity is even more critical issue when a new wireless technology may cause interference to a safety-of-life or military services. New rules in the spectrum management permit among other items the introduction of vehicular radar and other types of precision navigation equipment for vehicles and industrial or off-road equipment. Tests performed until the end of this year must show which UWB systems can indeed cause interference to existing systems and what strategy must be chosen to mitigate this interference.
This paper proposes a model of a multi-sensor system for detection and tracking of road vehicles and drones, based on developed original methods and algorithms for signal and data processing, which is a fundamental scientific task. The proposed model uses the polar Hough transform to combine the heterogeneous data in a multi-sensor system.KeywordsSmart citiesAir traffic managementComputer model
The electrification of vehicle helps to improve its operation efficiency and safety. Due to fast development of network, sensors, as well as computing technology, it becomes realizable to have vehicles driving autonomously. To achieve autonomous driving, several steps, including environment perception, path-planning, and dynamic control, need to be done. However, vehicles equipped with on-board sensors still have limitations in acquiring necessary environmental data for optimal driving decisions. Intelligent and connected vehicles (ICV) cloud control system (CCS) has been introduced as a new concept as it is a potentially synthetic solution for high level automated driving to improve safety and optimize traffic flow in intelligent transportation. This paper systematically investigated the concept of cloud control system from cloud related applications on ICVs, and cloud control system architecture design, as well as its core technologies development. Based on the analysis, the challenges and suggestions on cloud control system development have been addressed.
The time division multiple access (TDMA) technique has been applied in automotive multiple-input multiple-output (MIMO) radar. However, it suffers from the transmit energy loss, and as a result the parameter estimation performance degradation when the number of transmit elements increases. To tackle these problems, a transmit beamspace (TB) Doppler division multiple access (DDMA) approach is proposed. First, a phase modulation matrix with empty Doppler spectrum is introduced. By exploiting the empty Doppler spectrum, a test function based on sequential detection is developed to mitigate the Doppler ambiguity in DDMA waveform. Then, a discrete Fourier transform (DFT)-based TB in slow-time is formed. The proposed method can achieve waveform diversity in Doppler domain and generate a TB in slow-time that concentrates the transmitted power in a fixed spatial region to improve the transmit energy distribution for automotive MIMO radar, which is favored by medium/long range radar (MRR/LRR) applications. As compared to the conventional TDMA technique, the proposed TB DDMA approach can fully exploit the transmission capabilities of all transmit elements to ensure that the emitted power is efficiently used and inherits easy implementation. Moreover, the proposed TB DDMA method avoids the trade-off between the active time for each transmit antenna element and the frame time due to Doppler ambiguity mitigation. Simulation results verify the effectiveness of the proposed TB DDMA approach for automotive MIMO radar.
For accurate object vehicle estimation using radar, there are two fundamental problems: measurement uncertainties in calculating an object's position with a virtual polygon box and latency due to commercial radar tracking algorithms. We present a data-driven object vehicle estimation scheme to solve measurement uncertainty and latency problems in radar systems. A radar accuracy model and latency coordination are proposed to reduce the tracking error. We first design data-driven radar accuracy models to improve the accuracy of estimation determined by the object vehicle's position. The proposed model solves the measurement uncertainty problem within a feasible set for error covariance. The latency coordination is developed by analyzing the position error according to the relative velocity. The position error by latency is stored in a feasible set for relative velocity, and the solution is calculated from the given relative velocity. Removing the measurement uncertainty and latency of the radar system allows for a weighted interpolation to be applied to estimate the position of the object vehicle. Our method is tested by a scenario-based estimation experiment to validate the usefulness of the proposed data-driven object vehicle estimation scheme. We confirm that the proposed estimation method produces improved performance over the conventional radar estimation and previous methods.
For advanced active safety systems and autonomous vehicles, it is essential to predict target vehicle behaviors. Radar is a reliable vehicular sensor, but it has a degree of measurement uncertainty because of its operational mechanism and wandering reflection point. To deal with this problem, this paper proposes a radar accuracy model for object vehicle tracking to reduce the tracking error of the radar system. First, we divide the area uniformly and identify the surrounding vehicles using information, including relative position and relative velocity.We then analyze the error characteristics of each uniformly divided area. Next, we develop an occupancy zone-based Kalman filter for each area based on the error characteristics. We solve the problem that one cannot assign an exact zone for the object vehicle due to radar error by using interacting multiple model (IMM) filter. The performance of the proposed method is validated via experiments using radar and ground truth data.
The issues of introducing broadband technologies in civil and special purpose radar systems are considered. The popularity of these technologies for solving a number of practical problems determines the relevance of research related to a detailed analysis of long-range portraits of observed objects at a new qualitative level. The influence of the systematic error of the measuring channel on the reliability of the identification of the geometric shape of the local reflectors of the observation object using the results of broadband radar sounding is studied. The created broadband radar measuring channel with linear frequency modulation of the signal based on the method of generalized heterodyning is described. A technique is proposed for compensating systematic measurement errors for a channel of a given type using calibration spheres. The systematic error in measuring the frequency characteristics of the sphere is estimated, and an error indicator for estimating the frequency characteristics of objects is proposed. The dependence of the statistical indicators of the identification results of the geometric shape of local reflectors on the specified indicator is given. The possibility of identifying the geometric shape of local reflectors of objects by the parameters of their frequency characteristics has been experimentally confirmed. The results can be used to assess the reliability of identifying the geometric shape of local reflectors at the stage of calibration of the measuring channel, as well as to decide on the feasibility of implementing algorithms for identifying the geometric shape of local reflectors on an existing radar.
This paper represents the three dimensional array of SIW horn antenna for 24GHz applications, with improved gain when compared to the single antenna element and SIW horn antenna linear array structure. The two dimensional SIW horn antenna array does not satisfy the condition of half wavelength distance between the consecutive antenna element, hence the structure has poor gain. To improve the gain of a horn antenna a three dimensional structure is proposed. The combined beam of four antenna element provides the low HPBW radiation pattern. The maximum gain achieved from the structure is 8.8 dB at the desired frequency, whereas the single element SIW horn antenna has a maximum gain of 5.6dB. At 24 GHz, the SIW horn antenna is a good candidate for radar applications. Multiple horn antennas are combined to satisfy the high gain condition of automotive radar applications.
Short-range radar systems are non-contact devices that are attracting much attention from the RF/microwave community. In particular, they are starting to be applied in healthcare contexts, ranging from hospital to indoor and outdoor environments, e.g., for monitoring of vital signs and/or tracking of human activities. This manuscript reviews the standard architectures for short-range biomedical radars and presents recently-proposed hybrid schemes which combine different operation modes, leading to performance improvement. Specifically, hybridizations associated with Doppler, frequency-modulated continuous-wave (FMCW), and tone-ranging-based schemes are provided from theoretical and simulation viewpoints. Some experiments on vital-sign monitoring and human-aware localization are also reported.
This paper reviews recent progress of portable short-range noncontact microwave radar systems for motion detection, positioning, and imaging applications. With the continuous advancements of modern semiconductor technologies and embedded computing, many functionalities that could only be achieved by bulky radar systems in the past are now integrated into portable devices with integrated circuit chips and printed circuits boards. These portable solutions are able to provide high motion detection sensitivity, excellent signal-to-noise ratio, and satisfactory range detection capability. Assisted by on-board signal processing algorithms, they can play important roles in various areas, such as health and elderly care, veterinary monitoring, human-computer interaction, structural monitoring, indoor tracking, and wind engineering. This paper reviews some system architectures and practical implementations for typical wireless sensing applications. It also discusses potential future developments for the next-generation portable smart radar systems.
This chapter describes the emerging robotics application field of intelligent vehicles – motor vehicles that have autonomous functions and capabilities. The chapter is organized as follows. Section 62.1 provides a motivation for why the development of intelligent vehicles is important, a brief history of the field, and the potential benefits of the technology. Section 62.2 describes the technologies that enable intelligent vehicles to sense vehicle, environment, and driver state, work with digital maps and satellite navigation, and communicate with intelligent transportation infrastructure. Section 62.3 describes the challenges and solutions associated with road scene understanding – a key capability for all intelligent vehicles. Section 62.4 describes advanced driver assistance systems, which use the robotics and sensing technologies described earlier to create new safety and convenience systems for motor vehicles, such as collision avoidance, lane keeping, and parking assistance. Section 62.5 describes driver monitoring technologies that are being developed to mitigate driver fatigue, inattention, and impairment. Section 62.6 describes fully autonomous intelligent vehicles systems that have been developed and deployed. The chapter is concluded in Sect. 62.7 with a discussion of future prospects, while Sect. 62.8 provides references to further reading and additional resources.
Geht es um kommunizierende Maschinen, so sind Fahrzeuge besonders geeignete Anwendungsobjekte: Es gibt eine Vielzahl von Diensten, die es für Fahrzeugbesitzer wie Fahrzeughersteller gleichermaßen sinnvoll machen, Fahrzeuge mit Kommunikationseinrichtungen auszustatten. Wir geben einen Überblick über die wesentlichen Dienste, die aus der Vernetzung von Fahrzeugen ableitbar sind; den Schwerpunkt bildet dabei die vom Fahrzeug ausgehende Kommunikation, weniger die Kommunikation der Fahrzeuginsassen. Hinsichtlich dieser Dienste unterscheiden wir Client/Server- und Peer-to-Peer-Architekturen, die in jeweils unterschiedlichen Kommunikationsanforderungen und Systemgestaltungen resultieren. Wir untersuchen, in welchem Maße heutige Kommunikationsnetze diese Anforderungen erfüllen und widmen uns dabei insbesondere der direkten Fahrzeug-Fahrzeug-Kommunikation.
This Issue (DOI: 10.13140/RG.2.1.2030.7924) includes the following articles; P1110821003 N.Rajarajeswari and K.Thanushkodi A Bi-Directional DC- DC Converter with Adaptive Fuzzy Logic Controller P1110822001 A. Jeevanandham and K.Thanushkodi Optimization of Power System Stabilizers Relying on Particle Swarm Optimizers P1110825001 A. El Ougli, I. Lagrat and I. Boumhidi Direct Adaptive Fuzzy Control of Nonlinear Systems P1110820002 Fred Yu and Bozena Kaminska and Pawel Gburzynski A Wireless Sensor-Based Driving Assistant for Automobiles P1110830268 K.R.Valluvan and A.M.Natarajan Implementation of ADALINE Algorithm on a FPGA for Computation of Total Harmonic Distortion of load current P1110807002 S. DHBAIBI and A.S. TLILI and N. BENHADJ BRAIEK Decentralized Observer Based H8 Decentralized Control for Interconnected Systems
In this paper, we propose a time and memory efficient Ultra Wide Band Short Range Radar (UWB SRR) system for measuring relative target velocities of up to 150 km/hr. First, for the proposed detector, we select the required design parameters for good performance. The parameters are the number of coherent integrations, non-coherent integrations, and FFT points. The conventional detector uses a Fast Fourier Transform (FFT) to extract the range and velocity of the target simultaneously. Therefore, it requires high computation effort, high FFT processing time, and a huge amount of memory. However, the proposed pulse radar detector first decides the target range and then computes the target velocity using FFT sequentially for the decided range index. According to our theoretical and simulation analyses, the FFT processing time and the memory requirement are reduced compared to those of the conventional method. Finally, we show that the detection performance of the proposed detector is superior to that of the conventional detector in a background of Additive White Gaussian Noise (AWGN). © 2014 The Institute of Electronics, Information and Communication Engineers.
Das Forschungsprojekt FleetNet – Internet on the Road zielt auf den Einsatz von mobilen Ad-hoc-Netzen für die Fahrzeug-Fahrzeug-Kommunikation. Anwendungsgebiete sind sicherheitsrelevante Fahrerassistenzsysteme, dezentrale Floating-Car-Data-Anwendungen, sowie Kommunikations-und Internetdienste. Die Auswahl einer Funkhardware, die Entwicklung von geeigneten Kommunika-tionsprotokollen sowie die prototypische Demonstration der entwickelten Lösun-gen sind die Hauptziele. Wesentlich zu lösende Problemstellungen umfassen die Entwicklung von positionsbasierten Routingalgorithmen, das Kanalzugriffsproblem, die Bestim-mung und Anpassung einer geeigneten Funkhardware und die Kommunikation ins Internet über stationäre FleetNet-Stationen.
Today many people are greatly interested in the environment. Especially increasing affluent of food causes a great amount of food waste. To handle this effectively, we now have a lot of problems of disposing garbage all over the world. In Korea, in order to reduce this garbage, we should use a standard plastic garbage bag in which we have to throw away our garbage. So it has an effect on significantly reducing the waste amount every year. Now, there are a lot of cases that residents use several times a standard plastic garbage bag. The purpose of this study is to develop the recognition device preventing the re-cycling of a standard plastic garbage bag. As a result, we obtain 1% error rate.
This paper studies 24-GHz automotive radar technology for detecting low-friction spots caused by water, ice, or snow on asphalt. The backscattering properties of asphalt in different conditions are studied in both laboratory and field experiments. In addition, the effect of water on the backscattering properties of asphalt is studied with a surface scattering model. The results suggest that low-friction spots could be detected with a radar by comparing backscattered signals at different polarizations. The requirements for the radar are considered, and a 24-GHz radar for road-condition recognition is found to be feasible.
The paper presents details and results on a high-performance, medium-range monopulse radar system designed for various automotive applications, with a particular emphasis on the implementation and accuracy of the azimuth detection functionality. Whilst, by comparison, front-end radar systems for range and/or speed detection are relatively straightforward to implement, the addition of the azimuth functionality, indispensable in most automotive applications, is in fact an extremely difficult task. This task is even more challenging when such a system has to be low-cost. The system that we have developed is based on a compact low-cost Tx/Rx front-end design at 24GHz. A brief overview of the system and sub-system design details and their performances are outlined. Very reliable and accurate azimuth detection functionality has been implemented by employing a variant of the phase/amplitude comparison monopulse solution, using a high-performance patch-array antenna. Some of the main performance parameters achieved with the system described here include: range/speed detection of more than 50 meters, an azimuth range of plusmn 40deg with azimuth accuracy better than 1deg in the very important low-azimuth angle range. The paper includes some of the final system test results, showing the measured azimuth performance, for the antenna itself as well as for the entire front end system.
In this paper we simulated 24 GHz short range, wide band automotive radar. The simulation was done using matlab. The main objective of this work is to reduce traffic accidents and potential danger that faces the driver and the vehicle as a result of the sudden collision. The model consist of six sensors distributed in different sides of the car, these devices provide exact measurement of distance and relative speed of objects in front, beside or behind. Each sensor sends signals to predict, if there is any body around the car to alarm the driver about it. These signals cover distance reach to 30 m. However, if the distance between car & object was less than 2 m the car produce sound like alarm to alert the driver of danger near and the driver can present to take the appropriate decision to avoid collision.
This chapter presents a tetravision (4-camera) system for the detection of pedestrians by means of the simultaneous use of
two far infrared and visible camera stereo pairs. The main idea is to exploit the advantages of both far infrared and visible
cameras to develop a system that combines the advantages of using far infrared or daylight technologies. Different approaches
are used to process the two stereo flows in an independent fashion to produce a list of areas of attention that potentially
contain pedestrians. Then, four different following approaches are used to refine and filter this list and to validate the
presence of a pedestrian. Preliminary results show that the combined use of two vision systems as well as the use of different
and independent validation steps enable the system to effectively detect pedestrians in different conditions of illumination
and background.
Changing lanes while having no information about the blind spot area can be dangerous. We propose a vision-based vehicle detection system for a lane changing assistance system to monitor the potential sedan vehicle in the blind-spot area. To serve our purpose, we select adequate features, which are directly obtained from vehicle images, to detect possible vehicles in the blind-spot area. This is challenging due to the significant change in the view angle of a vehicle along with its location throughout the blind-spot area. To cope with this problem, we propose a method to combine two kinds of part-based features that are related to the characteristics of the vehicle, and we build multiple models based on different viewpoints of a vehicle. The location information of each feature is incorporated to help construct the detector and estimate the reasonable position of the presence of the vehicle. The experiments show that our system is reliable in detecting various sedan vehicles in the blind-spot area.
This paper describes a new waveform design for automotive applications based on CW transmit signals which lead to an extreme short measurement time. The basic idea is a combination of LFM and FSK CW waveforms in an intertwined technique. Unambiguous range and velocity measurement with high resolution and accuracy can be required in this case even in multi-target situations. After an introduction into FSK and LFM waveform design techniques in chapters 2 and 3 the combined and intertwined waveform will be described in detail in chapter 4. 2. PURE FSK MODULATION PRINCIPLE Pure FSK modulation (as shown in Figure 1 (a)) uses two discrete frequencies A f and B f (socalled two frequency measurement) [ART99] in the transmit signal. Each frequency is transmitted inside a so-called coherent processing interval (CPI) of length CPI T (e. g. ms 5 = CPI T ). Using a homodyne receiver the echo signal is down converted by the instantaneous frequency into base band and sampled N times. The frequency step A B Step f f f - = is small and will be chosen in dependence of the maximum unambiguous target range. The time-discrete receive signal is Fourier transformed in each CPI of length CPI T and targets will be detected by an amplitude threshold (CFAR). Due to the small frequency step a single target will be detected at the same Doppler frequency position in the adjacent CPI's but with different phase information on the two spectral peaks. The phase difference A B j j j - = D in the complex spectra is the basis for the target range R estimation. The relation between the target distance and phase difference is given by the following equation Step f c R
Radar sensors for automotive applications require extremely high performance figures in terms of measurement accuracy and time. LFMCW radar sensors have the advantages of high range resolution, but it will bring out ghost targets and missed targets in multi-target detection. This paper describes a new waveform combining LFMCW with SFCW pairing is proposed and discusses in detail to demonstrate the technical differences and advantages.
This paper presents a new concept and an experimental validation of a real&time driver assistance system involving multiple sensors and actuators monitoring an area around the vehicle and conveying alerts to the driver. The proposed system, dubbed the driving assistant, detects the presence of obstacles within the monitored area and alerts the driver via a combination of tactile, audio, and visual signals. It features simple ultrasonic sensors installed at the two front corners and the two blind spots of the vehicle. Our design is inexpensive and flexible, which makes it deployable as an add&on to existing vehicles. In particular, the interconnection of modules is achieved via a low&bandwidth low&power wireless link. We explain the rationale behind the driving assistant concept, discuss its performance within the context of human reaction time affecting the safety of vehicle operation, and suggest ways of incorporating such a system into real&life cars.
Tel: +49 (40) 42878-3228, Fax: +49 (40) 42878-2281 E-Mail: ebner@tu-harburg.de, rohling@tu-harburg.de SUMMARY In this paper a self-organized radio network for inter-vehicle communication (IVC) using broadcast messages is presented. The purpose of this network is to increase road traffic safety and to provide the driver with locally generated real-time traffic information. Therefore, each individual car transmits and receives broadcast packets that include floating car data (FCD) like position, velocity, road condition and visibility in a periodical way (e.g. every second). The periodical broadcast packets are also used to propagate summarized traffic information which has been received from other users in order to extend their accessibility far beyond the limited radio range of a single vehicle. Additionally, the transmission of delay-less data packets is foreseen in cases of emergency (e.g. crash, loss of traction), where an immediate and automatic reaction of the surrounding vehicles is required in order to prevent critical situations and further accidents. For collision-free access to the radio channel a reservation technique is considered which allows a self-organization inside the network. The system concept for a self-organized radio network and simulative results under realistic traffic situations are presented in this paper.
The first RADAR patent was applied for by Christian Huelsmeyer on April 30, 1904 at the patent office in Berlin, Germany.
He was motivated by a ship accident on the river Weser and called his experimental system “Telemobiloscope”. In this chapter
some important and modern topics in radar system design and radar signal processing will be discussed. Waveform design is
one innovative topic where new results are available for special applications like automotive radar. Detection theory is a
fundamental radar topic which will be discussed in this chapter for new range CFAR schemes which are essential for all radar
systems. Target recognition has for many years been the dream of all radar engineers. New results for target classification
will be discussed for some automotive radar sensors.
Most microwave sensors in the commercial market make use of Doppler effect in order to determine motion, velocity and direction of motion. If fixed object range information is required, the FMCW approach would be applicable, however, the hardware and processing (both analog and digital) efforts are extensive, especially for short range applications. Thus, a new short range radar transceiver sensor architecture has been developed which is capable of precise detection of object range and velocity down to a 15 cm distance. The new architecture has a broad range of industrial and commercial measurement applications and is particularly well suited for automotive parking, `stop & go' and air-bag deployment utilization. This technical presentation explores the high resolution radar sensor architecture, the principles of operation, and the component development. The development of the dielectric resonator oscillator, sampling mixer, high speed modulator, and patch antenna are individually reviewed. Operational results are presented which demonstrate the sensors ability to resolve the detection of object range and velocity. The high resolution radar sensor illustrates one of many practical, commercial applications for M/A-COM's semiconductor and subsystems capabilities.
Experiences with an experimental car controlled by a 77 GHz radar sensor
- H Rohling
- M.-M Meinecke
- M Klotz
- R Mende
H. Rohling, M.-M. Meinecke, M. Klotz, and R. Mende, “Experiences with an experimental car controlled by a 77 GHz radar sensor”, in Int. Radar Symp., Munich, Germany, Sept. 1998, vol. 1, pp. 345–354.
Experiences with an aperimental car controlled by a 77GHz radar sensor"; International Radar SymposiumA high resolution radar for short range automotive applications "; 28* European Microwave Conference
- H Rohling
- M.-M Meinecke
- M Klotz
H. Rohling, M.-M. Meinecke, M. Klotz, R Mende:,,Experiences with an aperimental car controlled by a 77GHz radar sensor"; International Radar Symposium 1998, Munich, Vol. 1, pp. 345-354, September 1998. W. Weidmann, D. Steinbuch:,,A high resolution radar for short range automotive applications "; 28* European Microwave Conference 1998, Amsterdam, pp. 590-594.
A high range resolution radar system network for parking aid applications
- M Klotz
- H Rohling
M. Klotz and H. Rohling, " A high range resolution radar system
network for parking aid applications ", in 5th Int. Conf. Radar Syst.,
Brest, France, May 1999.