Description
An RF gain equalizer (or simply equalizer) is a special type of attenuator designed to bring in frequency dependent losses opposite to those naturally present in a system. They are used to equalize the broadband insertion loss of a system with a particular frequency characteristic.
A common use-case for RF equalizers is to resolve the problem of wide-band microwave systems. Most of them have a negative gain slope (less gain, or more loss, the higher in frequency you go). This includes amplifiers as well as passive parts, such as coax cables and microstrip transmission lines. The solution to a system with a negative gain slope is adding a linear gain equalizer that has a positive gain slope, counteracting the effect.
Types of equalizers
Negative slope equalizers are normally used to offset the excessive loss of long cable runs at high frequencies. The loss parameter of the equalizer decreases linearly with frequency.
Positive slope equalizers are often used in applications to counteract undesirable loss of low frequencies where waveguide transmission characteristics require an equalizer that has increasing attenuation with frequency.
Parabolic equalizers are used in applications where a broadband traveling wave tube (TWT) or solid-state amplifier (SSA) has maximum gain or near the center of the frequency band. The characteristics of the equalizer require maximum attenuation at mid-band and decreasing attenuation at band edges.
Fine grain equalizers are used in broadband applications to flatten gain ripple and spikes. The narrow band attenuation is adjustable in the bands where the ripple or spikes arise and flatten the reaction in these sub bands.
Anything you need – we have it
We provide both standard and custom-designed equalizers to meet the requirements of any application, be it commercial, academic, or military. Design can be supplied that precisely define a preset loss characteristic (fixed equalizers) or with the ability to be loss-adjusted to custom-fit the variable requirements needed to field-tune a system. Equalizers can be custom made for each application to meet the needed performance parameters and package configurations.
