What is a Spectrum Analyzer?
A spectrum analyzer is a type of electrical measuring instrument.
The spectrum analyzer screen displays frequency on the horizontal axis and amplitude on the vertical axis, representing frequency as a component.
There are two types, one for high-frequency and the other for low-frequency, and each has different applications. The high-frequency version is mainly used to “display the distribution of frequency components” and “analyze the components of AC power” of the high-frequency signals of radio waves. In contrast, the low-frequency version is used for “noise analysis” and the like.
Since inaccurate results may be caused by static electricity, excessive power signals, etc., we recommend carefully checking the usage and conditions before use.
Uses of Spectrum Analyzers
High-frequency spectrum analyzers are used for inspection, measurement, design, repair, transmission wave, and the spurious measurement of radio equipment, transmitter, and receiver. Various setting items are important, so appropriate values must be entered according to the application.
For low-frequency applications, some products are small and portable and are widely used in field tests for field strength measurement, frequency identification, noise measurement, machine diagnosis, structural analysis, and vibration testing. in wireless run installation work.
Spectrum analyzers are sometimes compared and described with oscilloscopes. Typically, oscilloscopes are used with spectrum analyzers, which can capture and observe signals in terms of frequency, since they are often used to observe the time axis in the lower frequency range. oscilloscopes and spectrum analyzers observe signals from different angles and have different areas of expertise, so the necessary information should be considered before use.
Principle of Spectrum Analyzers
Heterodyne describes a signal processing technique and refers to the signal frequency created by converting the difference in frequencies generated by mixing or combining other frequencies with the received radio wave.
Superheterodyne generally refers to a reception method that converts the received signal into a fixed intermediate frequency (IF) that is easier to process than the original carrier wave. method are sometimes collectively referred to as superheterodyne.
In the superheterodyne-tuned sweep method, the input signal is passed through an attenuator and a low-pass filter while being limited by them. sweeps and measures the band-limited frequency with the frequency resolution set by the band-pass filter.
The FFT method has become popular in recent years due to its development. It is the same as the superheterodyne tuned sweep method up to the point where the input signal is frequency converted. In some cases, the output of the bandpass filter is converted to a digital signal by an AD converter and then the frequency is displayed by a fast Fourier transform. Since the time to measurement can be shortened, this method is suitable for measurement when the spectrum changes quickly.