Classification and function of signal generator
Signal generator is also called signal source. It could be divided to sine waveform generator, function generator, pulse signal generator, random signal generator and special signal generator according to generate signals’ types. Sine waveform generators provide most basic sine waveform signal which could be used as reference frequency and reference amplitude signal used for gain and sensitivity measurement and instrument calibration. Common high frequency signal generators and standard signal generators fall into this category. Function generators could generate all kinds of function waveform signals, such as square waveform, sine waveform, triangular waveform, saw tooth wave, pulse wave and etc.
Function signal generator is one signal generate device which could some specific periodic time function wave forms (sine waveform, square waveform, triangular waveform, sawtooth waveform, pulse waveform and etc), and the frequency could be from several to tens Dozens of megahertz. In addition to communication, instrumentation and automatic control systems for testing, but also widely used in other areas of non-electrical measurement.
Function of the function generator
The signal generated by the signal generator is often used in the circuit to replace the actual signal of the front-end circuit and provide an ideal signal for the back-end circuit. Since the characteristic parameters of signal source signals can be set manually, it is convenient to simulate signals with different characteristics in various situations, which is particularly useful for product research and development and circuit experiment. In circuit testing, we can measure and compare the input and output signals to determine whether the functions and characteristics of the signal processing circuit meet the design requirements.
Signal generators have wide application in production practice and scientific & technology area. Various waveform curves can be expressed by trigonometric equations. A circuit capable of producing a variety of wave forms, such as triangular waves, serrated waves, rectangular waves (including square waves), and sine waves, is called a function signal generator.
Function signal generator is widely used in circuit experiment and equipment test. In communications, broadcasting, and television systems, for example, you need radiofrequency (high-frequency) transmissions, where the radiofrequency wave is the carrier, and to carry out the audio (low frequency), video signal, or pulse signal, you need an oscillator that can produce high frequency. In industry, agriculture, biomedicine and other fields, such as high frequency induction heating, melting, quenching, ultrasonic diagnosis, nuclear magnetic resonance imaging, etc., all require power or small, high or low frequency oscillator.
The high-precision signal generator can also be used as a standard signal source (reference source) in the measurement and calibration field. It can be seen that the signal generator can be widely used in electronic research and development, maintenance, measurement, calibration and other fields.
Uses of function signal generators
produces the required parameters. According to its signal waveform, it can be divided into four categories:
(1) sine signal generator
It is mainly used for measuring frequency characteristics, nonlinear distortion, gain and sensitivity of circuits and systems. According to its different performance and use, it can also be divided into low frequency (20 HZ to 10 MHZ) signal generator, high frequency (100 KHZ to 300 MHZ) signal generator, microwave signal generator, sweep and program control signal generator, frequency synthesis signal generator and etc.
(2) Function (waveform) signal generator
It can produce some specific periodic time function waveform (sine wave, square wave, triangle wave, saw tooth wave and pulse wave, etc.) signal, the frequency range can be from a few micro-hertz to tens of megahertz.In addition to communication, instrumentation and automatic control systems for testing, but also widely used in other areas of non-electrical measurement.
(3) Pulse signal generator
It can be used to test the transient response of linear systems or as an analog signal to test the performance of radar, multichannel communications and other pulse digital systems.
(4) Random signal generator
It usually be divided to noise signal generator and pseudo-random signal generator. Main use of noise signal generator is a random signal is introduced into the system to measure the performance of the system by simulating the noise in actual working conditions. In addition, a known noise signal is compared with the internal noise of the system to determine the noise coefficient.The random signal is used instead of sine or pulse signal to measure the dynamic characteristics of the system. When the correlation function is measured by noise signal, if the average measurement time is not long enough, statistical error will occur, which can be solved by pseudo-random signal.