For the difference is that the spectrum analyzer provides the signal amplitude in the frequency domain, while oscilloscopes provide the signal amplitude in the time domain. Frequency domain of the signal provides information such as the harmonics present in the signal and noise levels that affect the signal at specific frequencies. Frequency domain spectrum analyzer display also provides the ability to see the signal strength at different frequencies.
All measurements are important from the viewpoint of RF circuits, testing and maintenance. Presents a plot or spectrum analyzer trace of the signal amplitude, to the frequency of the signal. The horizontal axis is calibrated to the frequency, with higher frequencies on the right side of the screen. The vertical axis is calibrated amplitude of the amplitude increases at the top of the screen. Frequency axis is calibrated in linear or logarithmic scale. Logarithmic scale to facilitate a wider range of frequencies that will be plotted on the horizontal axis. For devices with a logarithmic scale, amplitude scale is usually calibrated as 10 dB per division. Although the logarithmic scale of the spectrum analyzer provides a wider range of frequencies, does not give the absolute value of the signal. Linear scale, on the other hand, permits only a small band frequencies are shown. However, it provides the absolute value of the signal amplitude.
Types of Spectrum AnalyzerAnalog Spectrum Analyzer, Analog spectrum analyzer uses a bandpass filter. A bandpass filter is a filter that allows travel only a certain band of frequencies. Mid-frequency of this band is automatically set, the device, as the frequency changes. Loss of the full analog spectrum analyzer is that the frequency stability and wide bandwidth center frequency of the poor. Logarithmic display also gives an error in reading the decibel level of the signal.Digital Spectrum Analyzer, Digital spectrum analyzer using a Fast Fourier Transform (FFT) method to provide a frequency component of the frequency spectrum. This is an improved version of the analog spectrum analyzer. The accuracy of the signal amplitude increased. The accuracy of the amplitude of the two types. absolute accuracy and relative accuracy.
Absolute accuracy is relative amplitude in accordance with standards established by the national laboratories. The accuracy of the relative amplitudes of the two measurements is the ratio of the same amplitude and are not linked to national standards.Digital spectrum analyzer also maintain information regarding the phase and amplitude information of the signal within a certain frequency. Currently, the digital filter are two types, one which only measures the amplitude of the signal and the other that measures the phase of the signal. The device is also called a vector signal analyzer. Spectrum analyzer that provides both amplitude and phase information of the spectrum analyzer is called a hybrid. Hybrid spectrum analyzer allows analysis of the signal at higher frequencies with great accuracy and benefits of digital analysis is also included in the spectrum analyzer.Price is determined by the spectrum analyzer frequency range makes it possible to see. Furthermore, the resolution bandwidth and frequency stability are other criteria to be considered for adding to the cost. Although, these devices have complex circuitry and complicated work, it displays enough information about a particular signal. I took my post from the source that is http://www.buzzle.com.
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