Many data sheets for power amplifiers state the P1O ( 1dB compression point) and Psat (saturated power) levels of the device. what is the difference between them, are they same?
The saturation power is the maximum output power Ps. The one dB compression point is the point at the Po versus Pi curve where the saturation output power is reduced by one dB. I would like that you refer to the figure of Po vs.Pi in the link: https://ebrary.net/78582/computer_science/compression_point
Best wishes
Dear Hasan Malik , how are you ?
Considering the curve Pout x Pin, in the region where input power is small, the amplifier gain is constant. It is a linear region. However, when input power is increased, the gain is reduced. The 1dB compression point is the point whose gain of amplifier is reduced for 1dB. It is considered a region of moderate nonlinearity .
But, If keep increasing the input power (Pin) beyond the 1dB compression point, the gain continues reducing and output power keeps constant (approximately). In this case, is it found the saturation region - saturated power (Psat). It is strongly nonlinear.
Best regards,
Fabrício Simões
The saturation power is the maximum output power Ps. The one dB compression point is the point at the Po versus Pi curve where the saturation output power is reduced by one dB. I would like that you refer to the figure of Po vs.Pi in the link: https://ebrary.net/78582/computer_science/compression_point
Best wishes
Dear Hasan,
Abdelhalim abdelnaby Zekry and Fabrício Gerônimo Simões Silva have already provided the definitions. Just to add, Psat limit may be due to DC Supply level being reached, or/and other design factors.
Beyond the definitions part, the parameters are listed by vendors to help design the operational range based on multiple other factors like signal type, operating bandwidth, PAE, Supply Voltage, etc.
For a detailed understanding on a range of important RF design parameters you may want to refer to my book "RF & μWave Measurements: For Design, Verification and Quality Control" (ISBN: 9781075849398) available in amazon.
regards
spt
in addition to what has been said above I would like to stress that one can easily exceed the output power as defined by the 1 db compression point, however at the expense of more or less strong nonlinear distortions (depending on the type of amplifier).For narrowband amplifiers this may be part of the design using a bandpass filters after the PA. As a caveat: For wideband "HIFI" microwave power amplifiers (type A or AB) a nonlinear matching procedure for the output load can return much more available power at 1 db compression than the simple (linear) complex conjugate load.
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