## How is residual phase noise measured?

The residual phase noise of the amplifiers is measured by removing DUT1 and DUT2 from the circuit and applying the power splitter outputs directly to the amplifiers. The amplifier input signal power must resemble the actual DUT output signal in amplitude and slew rate.

What causes phase noise in a measurement?

Phase Noise is represented in the frequency domain of a waveform and consists of rapid, short-term, random fluctuations in the phase (frequency). This is caused by time domain instabilities (jitter).

How is phase modulation measured?

Phase modulation is calculated by adding the baseband signal to the argument of a sine or cosine function that represents the carrier. The modulation index makes the phase variations more or less sensitive to the behavior of the baseband signal.

### What is FM residual?

Residual FM is the undesired angular modulation or FM inherent in a signal generator with all the modulation turned off. It includes the effects of both spurious and phase noise. It is the integral or area under the SSB curve with limits set by the post- detection bandwidth.

What unit is phase measured in?

Instantaneous phase (ϕ) represents an angular shift between two sine waves and is measured in radians (or degrees). A sine wave and a cosine wave are 90° (π/2 radians) out of phase with each other.

How can I extend the dynamic range for sideband noise measurements?

With appropriate hardware it can be used to produce correlation spectra which can be used to extend the dynamic range for sideband noise measurements by 20 dB or more. Details here: Using average correlation spectra for sideband noise measurements with Linrad

#### What is the Rohde and Schwarz sideband noise study?

It is an investigation motivated by lack of agreement between measurements done with amateur equipment and those done with the FSUP from Rohde and Schwarz. The link shows how to measure sideband noise within a few tenths of a dB with amateur equipment.

How wide is an EME signal at 144MHz?

It is well known that an EME signal is about 300Hz wide at 10GHz because of the different doppler shifts from different reflection points on the moon. On 144MHz the EME signal is much narrower than one would expect from the frequency ratio.

Can WSE/linrad be used as a narrowband spectrum analyzer?

The WSE converters were developed before any direct sampling hardware was available. Linrad can be used as a high performance spectrum analyzer with the WSE units as well as with any other high performance hardware. This link some high resolution spectrademonstrates the capabilities of WSE/Linrad as a narrowband spectrum analyzer in the year 2004.