There are thousands of RF amplifiers made by hundreds of manufacturers from all over the world. To find an amplifier that that meets your requirement you need to know certain key parameters before you begin your search. Some of the key parameters are:
Frequency: RF amplifiers are usually designed to work at a particular frequency range as their performance can only be optimized for a select frequency range. The unit for frequency is Hz (Hertz).
Type: There are many types of rf and microwave amplifiers, each being used for a different application, some of the types being power amplifiers, low noise amplifiers, gain blocks, driving amplifiers, limiting amplifiers etc.
Gain: The gain of an rf amplifiers is the ratio of output to input power or amplitude - It can be seen as a measure of amplification. It's unit is decibels (dB), which is a logarithmic unit.
Noise Figure: Noise is an undesired signal that is generated upto some level in all electronics components and devices. Noise figure is the metric for noise performance is a circuit or system. It is measured in decibels (dB).
Power Compression (P1dB): P1dB or Power compression is the point at which the input signal is amplified by an amount, which is 1 dB below the small signal gain of the device. It is the point beyond which the gain of the device no longer increases linearly as you increase the power input to the device. The unit for P1dB is dBm or Watts.
Package Type: RF amplifiers are available in a number of package types such as surface mount, raw die's, connectorized with various connector options like SMA, BNC, TNC etc.
There are many types of rf amplifiers such as power amplifiers, low noise amplifiers, gain bloks etc. available from manufacturers and suppliers from all over the world. Each manufacturer having a catalog with their components. There are some online resources that compile all this information and make it searhable to users by specification. Using these online resources can save you time and the hassle of looking though individual company catalogs, websites and product lists to find the component you need.