函数通用信号发生器历史发展

历史发展

信号发生器是一种最悠久的测量仪器，早在20年代电子设备刚出现时它就产生了。随着通信和雷达技术的发展，40年代出现了主要用于测试各种接收机的标准信号发生器，使信号发生器从定性分析的测试仪器发展成定量分析的测量仪器。同时还出现了可用来测量脉冲电路或用作脉冲调制器的脉冲信号发生器。由于早期的信号发生器机械结构比较复杂，功率比较大，电路比较简单，因此发展速度比较慢。直到1964年才出现第一台全晶体管的信号发生器。

自60年代以来信号发生器有了迅速的发展，出现了函数发生器，这个时期的信号发生器多采用模拟电子技术，由分立元件或模拟集成电路构成，其电路结构复杂，且仅能产生正弦波、方波、锯齿波和三角波等几种简单波形，由于模拟电路的漂移较大，使其输出的波形的幅度稳定性差，而且模拟器件构成的电路存在着尺寸大、价格贵、功耗大等缺点，并且要产生较为复杂的信号波形则电路结构非常复杂。自从70年代微处理器出现以后，利用微处理器、模数转换器和数模转换器，硬件和软件使信号发生器的功能扩大，产生比较复杂的波形。这时期的信号发生器多以软件为主，实质是采用微处理器对DAC的程序控制，就可以得到各种简单的波形。软件控制波形的一个最大缺点就是输出波形的频率低，这主要是由CPU的工作速度决定的，如果想提高频率可以改进软件程序减少其执行周期时间或提高CPU的时钟周期，但这些办法是有限度的，根本的办法还是要改进硬件电路。

随着现代电子、计算机和信号处理等技术的发展，极大促进了数字化技术在电子测量仪器中的应用，使原有的模拟信号处理逐步被数字信号处理所代替，从而扩充了仪器信号的处理能力，提高了信号测量的准确度、精度和变换速度，克服了模拟信号处理的诸多缺点，数字信号发生器随之发展起来。

信号发生器的应用非常广泛，种类繁多。首先，信号发生器可以分通用和专用两大类，专用信号发生器主要为了某种特殊的测量目的而研制的，如电视信号发生器、脉冲编码信号发生器等。这种发生器的特性是受测量对象的要求所制约的。其次，信号发生器按输出波形又可分为正弦波信号发生器、脉冲波信号发生器、函数发生器和任意波发生器等。再次，按其产生频率的方法又可分为谐振法和合成法两种。一般传统的信号发生器都采用谐振法，即用具有频率选择性的回路来产生正弦振荡，获得所需频率。但也可以通过频率合成技术来获得所需9-率。利用频率合成技术制成的信号发生器，通常被称为合成信号发生器。

signal is a generator with the longest measuring instruments, as early as the 1920s when the emerging electronic equipment it has. As the communications and radar technology development, 40 in a major test for a variety of standard receiver signal generator so that the signal generator from the qualitative analysis of the test equipment developed into a quantitative analysis of the measuring instruments. At the same time there also can be used to measure pulse circuit or pulse modulator for the pulse generator. Since the early signal generator mechanical structure more complicated, more power, the circuit is relatively simple, relatively slow pace of development. Until 1964 there was the first all-transistor signal generator.

Since the 1960s, since the signal generator with the rapid development of a function generator, this period of analog signal generator use of electronic technology, by discrete components or analog integrated circuits constituted, the circuit structure complicated and can only have a sine Wave, square wave, sawtooth and triangle wave, and so few simple wave, because the analog circuit drift higher, to the extent of output waveform poor stability, but also pose a simulator of the circuit there is a large size, high prices, power-hungry , And other shortcomings, and to produce more complex waveforms circuit structure is very complicated. Since the 1970s a microprocessor, the use of microprocessors, ADC and DACs, hardware and software to expand the functions of the signal generator, a more complex waveforms. This time the signal generator and more software-based, is essentially a microprocessor on the DAC program control, you can get all kinds of simple wave. Waveform software control one of the greatest shortcomings of the output waveform frequency is low, mainly by the CPU speed of the work of the decision, if you want to increase the frequency can improve the implementation of its software program to reduce cycle time or increase the CPU clock cycle, but these options are limited The fundamental approach is to improve the hardware circuit.

With modern electronics, computers and signal processing technology, such as the development has greatly promoted the digital technology of electronic measuring instruments in the application of the original analog signal processing gradually being replaced by digital signal processing, thereby expanding the signal processing equipment , Increase the accuracy of the measurement signal, accuracy and speed of transformation, the analog signal processing to overcome the many shortcomings, digital signal generator then developed.

Signal generator is widely used, the wide variety. First of all, can signal generator at GM and dedicated two categories, the main signal generator dedicated to a particular measurement purposes of development, such as the television signal generator, pulse code signal generator, and so on. This generator is subject to the characteristics of the object measured by the constraints of the request. Secondly, the output waveform signal generator can be divided into sine wave signal generator, pulse-wave signal generator, function generator and arbitrary wave generator, and so on. Once again, according to a frequency of methods can be divided into resonant and synthesis of the two. Traditional use of the resonant signal generator, which uses a frequency selective circuit to generate sine vibration, to obtain the necessary frequency. But can also Synthesis technology to obtain the necessary 9 - rate. Frequency of use of technology into the signal generator, often referred to as synthetic signal generator.