What is amplifier linearity?
Linearity refers to the ability of the amplifier to produce signals that are accurate copies of the input. A linear amplifier responds to different frequency components independently, and tends not to generate harmonic distortion or intermodulation distortion.
How does a Doherty amplifier work?
The Doherty amplifier uses two amplifiers to optimize the overall PA performance. The carrier amplifier (or main amplifier) handles the low-power region while the peaking amplifier (or auxiliary amplifier) handles the high-power region. This sounds simple, but the practical implementation can be challenging.
What is Doherty amplifier state at high frequency?
The Doherty power amplifier is able to accommodate signals with higher peak to average power ratios whilst still retaining a good level of power efficiency. It achieves this by using two amplifier circuits within the one overall RF amplifier to accommodate the different conditions experienced.
What does high linearity mean?
Linearity is the behavior of a circuit, particularly an amplifier , in which the output signal strength varies in direct proportion to the input signal strength. The gain, or amplification factor, determines the slope of the line. The steeper the slope, the greater the gain.
What is a Class B amplifier?
Class B amplifier is a type of power amplifier where the active device (transistor) conducts only for one half cycle of the input signal. Since the active device is switched off for half the input cycle, the active device dissipates less power and hence the efficiency is improved.
What is a linearity range?
Linear range or linear dynamic range – The range of concentrations where the signals are directly proportional to the concentration of the analyte in the sample.
What is linear region?
Often we say “linear region” or “linear operation” in electronics when we mean in-between operation where a voltage is kept somewhere between the power supply rails (as apposed to clamped to near one of them) or a device like a transistor is kept in the middle region where it is not fully on or fully off.
What is audio linearity?
Linearity is the behavior of a circuit, particularly an amplifier , in which the output signal strength varies in direct proportion to the input signal strength. In analog applications such as amplitude-modulation ( AM ) wireless transmission and hi-fi audio, linearity is important.
What kind of amplifier is the Doherty power amplifier?
The Doherty power amplifier is an RF design of a class B amplifier configuration that achieves high efficiency by having two amplifier sections. One amplifier section caters for the lower amplitude signal situations.
What does the linearity of a PD mean?
Linearity of a PD implies the linear response of the device to input optical power. That is, the output electrical signal (i.e., the photocurrent), should vary linearly with the power of the optical signal incident on the device.
Why do you need a linear RF amplifier?
Many modern radio communications systems use high order QAM transmissions which have a high peak to average power ratio and require a linear RF amplifier. This normally leads to low efficiency in the final RF power amplifiers.
Which is a feature of Doherty active load modulation?
Furthermore, it is demonstrated in Section 9.4 that the digital Doherty architecture enables reconfigurable Doherty active load modulation, which can be utilized to compensate the antenna mismatches and achieve robust Doherty PA operation resilient to load variations.