Signal Design Research Articles

Improving Traffic Flow in Emerging Cities: A SIDRA Intersection Based Traffic Signal Design

Intersections in urban centers, especially those without any form of signalization, are accident hotspots. This, therefore, calls for ef-fective and efficient traffic management at the intersections for improved safety and efficient traffic flow. This study aimed to improve traffic flow at the Gaa-Akanbi intersection in Ilorin, Nigeria, using a traffic signal scheme. A traffic volume study and geometric features survey was carried out at the intersection. The traffic volume study was performed to determine the number, movement, and classification of vehicles at this intersection using the manual method of traffic count, while the geometric survey of the intersection was done using tape and Total Station. A 3-phase traffic signal was proposed. The optimum cycle length and signal setting were determined using SIDRA Intersection software by adopting the maximum average passenger car unit on the intersection and targeted level of service (LOS) "D". A traffic signal plan with a cycle length of 150 seconds was designed for the intersection. The amber time was considered to be 2 seconds for all phases, and green time of 48, 46 and 38 seconds was gotten for phases 1, 2 and 3, respectively; this timing ensures that minimum delay occurs at the intersection. The proposed traffic signal should be adopted at the intersection by the metropolitan traffic management agency to improve traffic management.

Multi-Timeslot Wide-Gap Frequency-Hopping RFPA Signal and Its Sidelobe Suppression

Random frequency and pulse repetition interval agile (RFPA) signals have excellent anti-jamming ability and achieve low probability of intercept (LPI), making them promising for applications in radar systems. However, their matched filter (MF) outputs suffer from random range-velocity sidelobes. In the range dimension, these sidelobes can be classified into two categories: the distant sidelobe floor spread out beyond the minimum interval between pulses, and the near sidelobe plateau confined within about one pulsewidth. These sidelobes seriously degrade the target detection capability of RFPA signals. To address this issue, we propose the concept of a multi-timeslot wide-gap frequency-hopping sequence (multi-timeslot WGFHS) and use it in the design of RFPA signals. In doing so, the distant sidelobes are easily suppressed with a simple low-pass filter (LPF) in the receiver if the parameters of the multi-timeslot WGFHS are chosen properly, while the remaining near sidelobes are suppressed by the iterative adaptive approach based on matched filter outputs (MF-IAA). Simulation results show that the proposed method can effectively suppress the sidelobes of RFPA signals, accurately recover the range-velocity images, and successfully detect weak targets in the presence of strong targets or clutter.

Selection and Design of Excitation Signal in Test System

Both the test system and testing technology are inseparable from the selection and construction of the excitation signal. This paper shows excitation signals including transient excitation, harmonic excitation, random signal excitation, etc, which are commonly used in the time domain, frequency domain, and correlation analysis of the stimulus-response test. Moreover, the selection and design method of excitation signals in the test system is introduced based on the principle of signal analysis and system identification, combined with research and engineering practice experience. The application of different excitation signals in modal tests and device characterization is described at the end of this paper.

Analyzing Harmony and Discord Among Optimal Building Controllers Responding to Energy, Cost, and Carbon Reduction Objectives

AbstractOptimization and control of building thermal energy storage holds great potential for unlocking demand-side flexibility, an asset that is being given much attention in current grid reforms responding to the climate crisis. As greater information regarding grid operations is becoming available, grid-interactive building controls inherently have become a multi-objective problem. Typical multi-objective optimization frameworks often introduce greater complexity and computational burden and are less favorable for achieving widespread adoption. With the overall goal of easing deployment of advanced building controls and aiding the building-to-grid integration, this work aims to evaluate the trade-offs and degrees of sub-optimality introduced by implementing single-objective controllers only. We formulate and apply a detailed single-objective, model predictive control (MPC) framework to individually optimize building thermal storage assets of two types of commercial buildings, informed by future grid scenarios, around energy, economic, environmental, and peak demand objectives. For each day, we compare the building’s performance in every category as if it had been controlled by four separate single-objective model predictive controllers. By comparing the individual controllers for each day, we reveal the level of harmony or discord that exists between these simple single-objective problems. In essence, we quantify the potential loss that would occur in three of the objectives if the optimal control problem were to optimally respond to only one of the grid signals. Results show that on most days, the carbon and energy controllers retained most of the savings in energy, cost, and carbon. Trade-offs were observed between the peak demand controller and the other objectives, and during extreme energy pricing events. These observations are further discussed in terms of their implications for the design of grid-interactive building incentive signals and utility tariffs.

Command filter based adaptive finite‐time dynamic surface control for nonlinear systems with unknown input delay under discontinuous input

AbstractIn this article, the adaptive finite‐time quantized and event‐triggered dynamic surface control (DSC) schemes are proposed for a class of strict‐feedback nonlinear system with time varying input delay. In order to ensure the completeness of the DSC method, an improved dynamic surface control method based on command filtering is adopted. The designed filtering error compensation signal can not only effectively compensate the filtering error, but also deal with the discontinuous input possessing unknown input delay. The problem of finite‐time control design and stability analysis with the difficulties brought by discontinuous input with unknown time‐varying input delay is solved through the design of the new compensation signal and the corresponding Lyapunov functional. Theoretical analysis shows that all signals in the closed‐loop system are bounded in finite time. The simulation examples also verify the effectiveness of the adaptive finite time DSC schemes proposed in this article.

Research on Signal Transmission Device of Multi Adaptive Coiled Tube Measurement and Control System

As an important technology for oilfield development and oil and gas reservoir reconstruction, the demand for coiled tubing logging, perforating, fracturing and acidizing and other process operations has increased dramatically, and downhole testing and control operations must be completed through downhole data acquisition and transmission and control signals. However, at present, the special cable coiled tubing roller device and logging roller operating machine mainly used at home and abroad have problems such as single function, high cost, complex structure, and poor versatility. Therefore, based on the structural characteristics of the conventional coiled tubing machine, through the analysis of the existing coiled tubing testing and control data signal transmission system, the research and design of the signal transmission device for the multi adaptive coiled tubing measurement and control system was completed, and a kind of signal transmission device for the multi adaptive coiled tubing signal testing, acquisition, transmission and feedback control system with strong versatility and high transmission efficiency was studied and designed, It eliminates the high cost of traditional equipment customized processing and manufacturing and the high labor intensity of operation and maintenance operations caused by the single adaptability of operation process, which are caused by complicated structures. It is of great significance for realizing the transformation and upgrading of the multi-function of intelligent measurement and control integration of coiled tubing machine, and is extremely important for the innovation of the digital network real-time monitoring system for future oilfield development.

Signalling Design in Sensor-Assisted mmWave Communications for Cooperative Driving

Signalling Design in Sensor-Assisted mmWave Communications for Cooperative Driving

Design of Software-Based Optimal Signals for System Identification

Design of Software-Based Optimal Signals for System Identification

Waveform Design and DoA-DoD Estimation of OFDM-LFM Signal Based on SDFnT for MIMO Radar

In comparison to orthogonal frequency division multiplexing (OFDM), the OFDM linear frequency modulation (OFDM-LFM) signal has similar time-bandwidth product, lower peak-to-average power ratio, and higher sensitivity to Doppler frequency shift, making it a promising candidate waveform for multiple-in multiple-out (MIMO) radar applications. However, the OFDM-LFM signal is unsatisfactory in practical applications due to the challenges in waveform design and its non-stationary property, which significantly degrades the performance of current high-resolution subspace techniques for direction of departure (DoD) and direction of arrival (DoA) angle estimation. In this paper, we first proposed a novel OFDM-LFM waveform design method based on the scale discrete Fresnel transform (SDFnT), which efficiently generates orthogonal LFM signals with unlimited number of subcarriers and can be convieniently implemented using the fast Fourier transform (FFT). Then, for angle estimation in OFDM-LFM MIMO radars, we presented a new scale discrete Fresnel transform multiple signal classification (SDFnT-MUSIC) method. By converting the steering vector into the chirp domain and making it non-time-vary, high resolution angle estimation for OFDM-LFM wideband signals can be achieved. Simulation results shows that the proposed waveform design method requires less computational time than conventional method based based on the fractional Fourier transform (FrFT), whereas the proposed DoA-DoD estimation method outperform the FrFT-MUSIC method in terms of computational complexity and target angle estimate performance.

Fractional System Identification using Binary Measurements

This paper focuses on the identification of commensurate fractional order systems from binary measurements on the output. The proposed algorithm allows the estimation of both the parameters of the model and the commensurate order. The algorithm is based on a specific design of the output signal as a sum of sinusoids. It allows the parametrization of the output signal on a basis of sinusoids and the estimation of the high resolution output. Numerical simulation results are provided to show the efficiency of the method.

Spatially-Coupled Faster-Than-Nyquist Signaling: A Joint Solution to Detection and Code Design

In this paper, we investigate two important issues of faster-than-Nyquist (FTN) signaling, namely, reduced-complexity detection and code design. Different from previous works, we consider these two issues jointly by designing a scheme that increases the minimum squared Euclidean distance of FTN signaling via repetition coding at a cost of an increased complexity. Furthermore, to reduce the rate loss of the repetition, we adopt the idea of spatially-coupling from coding theory to FTN signaling, and the resultant signaling scheme is therefore referred to as spatially-coupled faster-than-Nyquist (SC-FTN) signaling. The signal of SC-FTN signaling is generated in a continuous manner by interleaving and repeating the coded FTN signals and a graph-based iterative sliding-window detector is applied for signal detection. Both bounding and extrinsic information transfer chart analysis are provided to study the error-floor and convergence performances of SC-FTN signaling. These analyses unveil the intrinsic relationship between error floor, decoding threshold, and detection/decoding complexity, which provides guidelines for the designs of practical systems. Simulation results show that the promising error performance can be achieved with a simple FTN detection, where the bit error rate performance of coded SC-FTN signaling outperforms that of state-of-the-art coded FTN systems and the capacity of Nyquist signaling.

Algorithms for composing communication protocols of wireless sensor networks with random access

The work is devoted to solving the problem of applying information technology methods and tools to monitoring environmental parameters based on the Internet of Things concept, taking into account the uncertainty of information sources and the possibility of critical situations. The principles of construction, technological solutions and directions of development of environmental monitoring systems are analyzed. The advantages and disadvantages of the known approaches are revealed and the expediency of constructing mathematical models, methods and algorithms for compiling communication protocols of WSN wireless sensor networks with random access and corresponding information technologies for monitoring environmental parameters to ensure high performance, quality and survivability of their functioning is proved. Stochastic models of the functioning of wireless sensor networks have been improved, which made it possible to estimate the probability of signal collisions and design Internet of Things communication protocols more efficiently.

信号与系统课程思政设计——以傅立叶变换章节为例

信号与系统课程思政设计——以傅立叶变换章节为例

Signaling Design for Cooperative Resource Allocation and Its Impact to Message Reliability

Signaling Design for Cooperative Resource Allocation and Its Impact to Message Reliability

Optimal Signal Design in System Identification for Model Predictive Control (MPC)

Optimal Signal Design in System Identification for Model Predictive Control (MPC)

Model distillation for high-level semantic understanding：a survey

Model distillation for high-level semantic understanding：a survey

A MULTI-OBJECTIVE OPTIMIZATION FRAMEWORK FOR TRAFFIC SIGNAL DESIGN

Traffic signal design requires experienced traffic engineers to decide on the phasing plans and then timing plans can be optimized. However, the available guidance provides general recommendations for phasing planning; while, commercial software optimizes the timing plans and corresponding operation performance (e.g., best performance index). Furthermore, the performance index excludes safety factors. This research aims to develop a framework that can deliver a phasing plan by enumerating all possible solutions and then selecting the phase plan that achieves the objectives. These objectives are to minimize the severity, average delay, and queue length. A program (i.e., software) has been developed to perform these stages and deliver a sorted list of phase plans based on the assessment criteria considering different traffic patterns, different intersection lane configurations, and operation types for left and right turns. A validation exercise was performed to assess the effectiveness and practicality of the developed software. It includes designing a phase plan for fifteen American, Canadian, and Chinese intersections and comparing them against their actual phasing design in terms of safety, average delay, and queue length. The results show that on average, the safety level is improved by 19%; however, the delay and queue length increased by 33% and 13%, respectively. The results encourage extending the proposed framework to consider the phasing sequence and coordination in future work. Finally, it is found that the framework provides practical phasing plans in terms of safety and other operational aspects. The results encourage extending the proposed framework to consider the phasing sequence and coordination in future work. Keywords: Traffic Signal Optimization, Phasing Plan, Highway Safety Manual, Queue Length DOI： https://doi.org/10.35741/issn.0258-2724.58.1.37

Active Fault Detection Based on Auxiliary Input Signal Design

Active fault detection (AFD) is considered an effective incipient failure-detection method. In this paper, an auxiliary input resonance signal proposal that can detect different incipient faults quickly while keeping the system stable is proposed for AFD. To maintain the stability of the system, auxiliary input signals with a sinusoidal form, which should minimize and maximize the effect in fault-free cases and fault cases, are designed on the YJBK parameterization architecture. Subsequently, the fault detection signal is transferred from the traditional system output signal to the cumulative sum of the designed residual signal. Finally, some illustrative examples are given to indicate the effectiveness of the proposed unified operation architecture and some encourage results have been obtained, the simulation results show that the designed auxiliary input signal can not only ensure the normal operation of the system, but also quickly and effectively detect the occurrence of minor faults.

Cooperative Output Regulation of Linear Multiagent Systems With Parameter Convergence

In this article, a new cooperative control protocol with parameter convergence is developed to address the problem of cooperative output regulation (COR) of linear multiagent systems (MASs). First, the utilization of the regulator equation overcomes the difficulty of related filtering signal design owing to the absence of matching conditions between the leader system matrix and that of the followers, which is essential for concurrent learning. Then, with the light of the proposed observer, a specific relationship between two sets of constructed filtered signals is satisfied after a finite time, which lays the foundation for a concurrent learning strategy. Furthermore, a cooperative controller with the cooperative adaptive law is successfully constructed, which overcomes the difficulty of controller design caused by estimations of the leader system matrix not satisfying regulator equation. Compared with the existing studies, the cooperative finite-time excitation (cFTE) condition is successfully applied to the COR of MASs for the first time. The developed controller can ensure accurate identification of adaptive parameters and output regulation control simultaneously. As a result, better system performance can be achieved. Finally, the effectiveness of our method is verified by a simulation example.

Smart signal design and implementation of the trash can

Smart signal design and implementation of the trash can