Design Of Signal Generator Research Articles

A hierarchical design framework for distributed control of multi-agent systems

In this paper, a hierarchical design framework is proposed for distributed control of multi-agent systems. Different from the traditional distributed design philosophy that directly couples the agents’ cooperation and individual regulations, the proposed framework decouples these regulations and separates the distributed control design into two layers, i.e., the layer of reference signal generator design and the layer of tracking controllers design. Specifically, the nodes of the generator play the roles of some virtual agents that achieve the distributed control goal and the agents’ tracking controllers are used to track the reference signals produced by the generator. The novel design framework makes the agents reach the distributed control goal well and it has better design flexibility/practicality and stronger versatility/scalability. To demonstrate these advantages, two types of representative examples on hierarchical design are exhibited for multi-agent systems with mismatched disturbances and those with communication/input delays, respectively. All examples confirm that the proposed design framework is a natural choice in the presence of some complex factors, which provides not only simpler design but also more autonomy to the agents.

Algorithm for designing low-noise frequency synthesizers for remote sensing systems

Frequency synthesizer is an important component of radar tracking system for remote sensing. Synthesizers generate wideband radio frequency signals with high frequency resolution. Parameters of radar depend on the synthesizers phase noise. This paper presents algorithm for structural design of signal generators based on various synthesis methods: direct, indirect and hybrid ones. Specialized software based on presented algorithm was developed in this work. Software allows calculating frequency ratios in the structure of synthesizers, selecting optimal parameters which can provide low phase noise level. Also software allows performing mathematical modelling and analysis of phase noise power spectral density (PSD) of frequency synthesizers. Presented algorithm and software can be useful for developers of remote sensing radio systems.

Design of Signal Generators Using Active Elements Developed in I3T25 CMOS Technology Single IC Package for Illuminance to Frequency Conversion.

This paper presents a compact and simple design of adjustable triangular and square wave functional generators employing fundamental cells fabricated on a single integrated circuit (IC) package. Two solutions have electronically tunable repeating frequency. The linear adjustability of repeating frequency was verified in the range between 17 and 264 kHz. The main benefits of the proposed generator are the follows: A simple adjustment of the repeating frequency by DC bias current, Schmitt trigger (threshold voltages) setting by DC driving voltage, and output levels in hundreds of mV when the complementary metal-oxide semiconductor (CMOS) process with limited supply voltage levels is used. These generators are suitable to provide a simple conversion of illuminance to frequency of oscillation that can be employed for illuminance measurement and sensing in the agriculture applications. Experimental measurements proved that the proposed concept is usable for sensing of illuminance in the range from 1 up to 500 lx. The change of illuminance within this range causes driving of bias current between 21 and 52 μA that adjusts repeating frequency between 70 and 154 kHz with an error up to 10% between the expected and real cases.

Pulsar Based Alternative Timing Source for Grid Synchronization and Operation

The need for timing sources that are alternatives to GPS has been under consideration for years. The reliance of power systems instrumentation and control systems on GPS timing serves as the basis for the study reported in this paper. The issues associated with grid timing requirements are reviewed within the context of a GPS-based clock source. Of principle investigation is the possibility of using millisecond rotation neutron stars, pulsars, as the alternative time source. A design of an instrument (referred to as a pulsar based timing instrument, PBTI) that would use stable and accurate pulsar signals for grid timing is presented. The described PBTI design has been logically separated into software and hardware segments. Flexible signal processing is performed in software which will transfer the raw pulse data from the pulsars into a pulse per second (PPS) signal which can be directly utilized in the power system components and applications. The hardware aspects of the PBTI design concentrate on the antenna requirements, with specific concern associated with the required size and pointing/tracking needs, back-end, filters, amplifiers, and signal generator design. An overall block diagram and the detailed descriptions of both the software and hardware designs are presented. Finally, the potential future applications and problems of the pulsar based timing instrument are discussed.

Design of signal generator for mine-used mud pulse wireless measurement while drilling

Design of signal generator for mine-used mud pulse wireless measurement while drilling

Raspberry PI 3 RF signal generation system

Radio frequency signal generators (RF) are instruments used to test reception equipment and RF components like filters, amplifiers, attenuators, among others. On the other hand, they reinforce the teaching-learning processes and they are widely used in research in the telecommunications field. This document provides the first stage of a low-cost signal generator design by using RaspBerry Pi 3, with the documentary exploration about this kind of applications. After that, a recognition of the RaspBerry Pi 3 is done at hardware and software level. Finally, an application of an FM signal generator with RaspBerry in a frequency of 101.3 MHz is evaluated, which does not require any additional hardware. This signal was captured using a spectrum analyzer, which determined good quality of the modulated signal in terms of power, bandwidth and SNR (Signal Noise Ratio). However, there are some unwanted harmonic components

Design of a High-Voltage Signal Generator Applied Flashover Fault Detection

For cable flashover failure, a signal generator design ideas of the NC DC high flash - DC medium voltage flash - low-voltage flash based on three pulse method, consists of three components: the DC source, medium-high pressure unit and low pressure unit. DC source adopts AC 220V power supply, after rectification, chopping booster output. The output of the DC source through an inverter and high-frequency boost get the high-voltage unit. Low unit through the high-speed switching devices and capacitor charging and discharging achieve nanosecond pulse generation. In this paper, the various aspects of the design of the system have made a detailed description and simulation research.

The Design of Signal Generator Based on FPGA High Resolution

In view of the digital geophone self-test system application demand for a variety of high quality waveform signal. This paper introduces a kind of design method of direct digital synthesis waveform signal generator based on FPGA. It mainly discusses the principle of the method of frequency synthesis technology, design thinking and implementation method. And using the design method of pipeline structure to improve circuit structure of 48 bits phase accumulator, so as to improve the running speed, and further increase the resolution of frequency synthesis. The test shows that the signal generator can produce sine wave, square wave, sawtooth wave, triangle wave. The frequency resolution can reach 0.18μHz. The highest output frequency is up to 20MHz, and frequency switch time is 20ns.

The Design of Signal Generator with DDS Based on FPGA

Direct Digital Synthesizer （DDS） is a new theory starting from the conceptual phase required for the direct synthesis of waveforms, This system in the FPGA chip and D/A conversion circuit, filter circuit, amplitude amplification circuit and power amplifier circuit's support to achieve a meet scheduled targets multiple waveform output.

The Design of Signal Generator in Motor Function Rehabilitation Based on MCU

Objective: In order to promote paralyzed patients’ recovery of their motor function, we designed this functional electrical stimulation (FES) signal generator. Method: We used AT89C52 MCU and digital analog converter as the core to compose hardware system. By analyzing the time domain characteristics of common waveforms and the movement-related neural signals, we designed the corresponding MCU program, then the expected waveforms can be generated as signal sources of this therapeutic apparatus. Results:This signal generator is able to produce series of waveforms in the time domain, such as sine wave, rectangular wave, triangular wave signal, and neural signal bands related with movement .Conclusion: Compared with the traditional signal generators [1], this signal generator has the advantages of simple structure, complete functions, low cost and convenience. Using movement-related neural signals which were collected from animal experiments as signal sources is helpful to induce the coordinated movement and reduce the muscle fatigue.

The Dual Sine Signal Generator Design Based on the Principle of Difference Frequency Filtering

The paper attempts to realize the processing scheme of low cost dual sine wave generator. It used single-chip microcomputer and CPLD(Complex Programable Logic Device) as the control core. It maked use of CPLD and discrete component simulations to implement DDS principle. It utilized the filter circuit, integrated op-amp circuit and multiplier circuit instead of DAC chip. The range of frequency, amplitude and phase difference are 1Hz~1000Hz, 1V~3V and 0o~359o, respectively. The results show that a 2-channel sine signal generator can be designed with adjustable frequency, amplitude and phase difference.

Theoretical study of electric energy consumption for self-powered chaos signal generator

Self-powered chaos signal generator is potentially useful in future medical system, such as low cost portable human healthy monitor and treatment without external power source. For both functional and power unit, the power level of electric energy generator and consumption is a key factor for self-powered system. In this paper, we have investigated the power consumption of three typical output modes of a simple chaos circuit. Analytical analysis for power consumption of fixed output mode is obtained for evaluating the power characteristics of chaos signal generator. Numerical calculations are given for predicting the power characteristics of periodical and chaotic output modes. This study is important for not only understanding the power consumption of chaos signal generator, but also guiding new self-powered chaos signal generator design.

Simplified Analogue Realization of the Digital Direct Synthesis (DDS) Technique for Signal Generation

The design of signal generators has evolved through various analog techniques and in the recent years has seen the adoption of digital design methods owing to tremendous advantages that digital methods offer over analog. This work studied Direct Digital Synthesis (DDS) technique and the implementation was done using simplified yet innovative approach to realize the memory data storage of signal points on look-up tables in a PROM and also the DAC.

Design of Signal Generator Based on DDS Technology

Traditional signal generators use analog oscillator circuit as the source, which often involve multiplication, integral and differential circuit. As this method required high electrical parameters of the system, and its complex circuit structure is vulnerable to outside interference. In this paper, a new technology named Direct Digital Synthesizer, DDS technology, was applied on a FPGA chip to design a waveform generator. It can generate periodic waveform, and its frequency, phase and amplitude were adjustable. Simultaneously, DDS technology has the function of frequency and phase adjustment, so no additional circuit was needed. During the amplitude modulation design, the characteristics of reference voltage of the D/A Converter are used. The theoretical and experimental results show that the combination of DDS technology and FPGA can well generate the periodic signal waveforms, while the hardware system fabricated has strong capability of anti-jamming.

Design and Implementation of Signal Generator Based on DDS

A signal generator with adjustable frequency, phase and duty cycle is designed in this paper. The design of this signal generator is based on the technology of direct digital synthesis (DDS).The classic structure of DDS is presented and its principles are introduced in detail. The key modules of the design such as phase accumulator and pulse width processing are implemented by verilog HDL language. With suitable FPGA, the designed signal generator and all modules of the design are simulated successfully in Quartus II.

A Design Method of Signal Generator Based on DSP6713 and D/A Converter

The system completes the design of signal generator by using the technology of the Direct Digital Synthesizer (DDS). The DSP6713 designed as a key device, realizes outputting triangle wave and sine wave. The digital to analog (D/A) converter circuit is composed of AD768 and LTC1597, which helps improve the speed of converting and modulate the range of the output voltage by Digital Signal Processor (DSP), comparing with using one chip of D/A and proportional amplifier. In addition, bus topology makes extending system functions become easy. The system can be widely used in such field as communication, automatic control and instruments.

Signal Generator Design Based on the FPGA

this paper introduces an output method of arbitrary waveform signal on the FPGA by uses DDS principle. Arbitrary waveform dates produced by the upper machine are downloaded to the waveform RAM of the DDS through the serial port, and realize the control of frequency and phase by using single-chip microcomputer. The upper machine with using LabWindows/CVI software design, realizes arbitrary waveform output.

Signal Generator Based on Direct Digital Synthesis Techniques

This paper describes a design of signal generator based on direct digital synthesis technique (DDS). According to the basic principles of DDS using Matlab/DSP Builder establish DDS model, then compiling by the SignalCompiler tools and generating VHDL code. Finally download the relevant documents to the field programmable gate array (FPGA) chip EP2C5Q208C8N. EP2C5Q208C8N and digital-analog chip DAC908, high-speed operational amplifier THS4001 together to complete the signal generator’s hardware design. The system can output sine wave, square wave, triangle wave, phase shift keying (PSK), amplitude shift keying (ASK) and frequency shift keying (FSK). It’s stable, reliable and fairly practical.

Multi-channel DTV signal generator design using modified Farrow filter

This paper proposes a compact multi-channel DTV signal generator. To combine multi-channel signal sources in digital domain, the baseband signal is up-sampled and interpolated using the modified Farrow-type filter. We formulate the optimization problem and design the filter coefficients. The designed filter contains a small number of multipliers with more than 40dB sideband signal suppression capability.

Design principles for electronic signal generators with prescribed power

We consider principles for design of signal generators of prescribed power for instrumentation purposes. We present block diagrams and their analysis.