# phase shifter Phase shifters are a key building block in RF circuits, used in beam steering, amplifier linearisation (gain/phase adjustment in a distortion cancelling loop) etc. [^1] ## Important Characteristics - [insertion loss](insertion%20loss.md) (preferably low) - Equal amplitude for each phase ## Design parameters - phase control range - [insertion loss](insertion%20loss.md) - [phase resolution](phase%20resolution.md) - [noise](noise.md) - [Bandwidth](../General/Bandwidth.md) - [rf large signal capabilities](rf%20large%20signal%20capabilities.md) - [chip size](chip%20size.md) ## Uses of Phase Shifters Change the transmission phase angle (phase of S21) ## Active Phase Shifter See [Active phase shifter](Active%20phase%20shifter.md) Provide gain, introduce non-linearity ## Passive Phase Shifter See [Passive phase shifter](Passive%20phase%20shifter.md) Better large signal performance but show [insertion loss](insertion%20loss.md). ## Varactors ## TR Modules See [TR Modules](TR%20Modules.md) >It is funny how over the past ten years, more and more TR module architectures are using a "common leg" circuit that includes phase control. Because of this, the one advantage of a passive phase shifter no longer matters. It seems just a matter of time before someone reinvents the active phase shifter in a TR module. Maybe that has happened already, just [send us a reference](mailto:[email protected]) and we'll post it here. --- # References 1. [High Resolution Integrated Passive Phase Shifters for Future Wireless Communications](High%20Resolution%20Integrated%20Passive%20Phase%20Shifters%20for%20Future%20Wireless%20Communications.md#Chapter%205%20-%20Literature%20Review%20on%20phase%20shifter%20s) 2. [Microwaves101 | Phase Shifters](https://www.microwaves101.com/encyclopedias/phase-shifters)