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the marker (number of points depends on the microwave analyzer), which normalizes the power within
the 1 Hz equivalent noise bandwidth.
Phase noise (noise sideband)
The oscillator in the microwave analyzer is used to convert the input signals of different frequencies to
the intermediate frequency. The phase noise represents the relative value of the noise power and carrier
power in the 1 Hz equivalent noise bandwidth at a certain frequency offset of the carrier, which is
commonly expressed in dBc/Hz. It is a measure of the oscillator's short-term frequency stability, which is
caused by phase or frequency variations, and is expressed as a bell-like noise characteristic in the
oscillator signal. It affects the measurement ability of the whole machine to the phase noise of the
measured signal, and also affects the sensitivity and dynamic range of the whole machine.
Gain compression
If the input signal level is increased, the mixer circuit, amplifier and other unit circuits of the microwave
analyzer may work close to the saturation point. At this time, the output signal component no longer
changes linearly with the input signal, and the displayed signal level is low, which is caused by gain
compression. A 1dB (or 0.5dB) expression point is expressed typically with the input level corresponding
to the output linear value deviation of 1dB (or 0.5dB).
Positive peak detection mode
A display detection method for signal energy, each displayed point corresponds to a plurality of detected
sample data points of a video signal in a portion of a frequency span or time interval represented by the
point, and then the maximum of the data points is extracted, which is called positive peak detection
IF gain/IF attenuation
The IF gain/IF attenuation is an IF controller that adjusts the vertical position of the signal on the display
without affecting the signal level on the input mixer. If the IF gain/IF attenuation is changed, the reference
level also changes accordingly.
Maximum input level
The maximum input level is divided into the maximum input level with no degradation in performance
and maximum safe input level. The former represents the maximum level added at the input that does
not cause a degradation in product performance, and the latter represents the maximum level allowed by
the input without damaging the product. The maximum safe input level value of continuous wave
average power, peak pulse power (indicating pulse width and duty factor), and the DC voltage specified
in the product specification.
Rev Iso
The reverse isolation measures the reverse transmission response of the amplifier from the output to the
input, and measures the isolation of the device of output to the input. An ideal amplifier should have
infinite reverse isolation and have no signal coming back from the output to the input. However, in
practice the signal may pass through the amplifier in the opposite direction. This undesired reverse
transmission may cause the reflected signal at the output port to interfere with the desired signal for
forward transmission, so it is important to quantify the reverse isolation.
Group delay
Group delay is a method of measuring the phase distortion of a device. It is the transit time of the signal
passing through the device, which varies with frequency and is the derivative of the phase/frequency
feature of the device. The phase distortion of the kit to be tested can be measured by the group delay
measurement.
Return loss
The easiest way to represent reflected data is return loss, which is a scalar and expressed in dB. The
return loss is the dB value of the reflected signal below the incoming signal. When the impedance is
completely matched, the return loss is infinite. For an open circuit, short circuit or lossless reactance
circuit, the return loss is 0 dB.
VSWR
When two sets of waves are transmitted in the opposite direction on the same transmission line, they will
cause a standing wave, which can be expressed by the voltage standing wave ratio (VSWR or SWR for
