Reflection-type low-phase-shift attenuator

A transmission-type phase-shift attenuator has a poor reflection characteristic at an output port. In this paper, to avoid such disadvantages, a reflection type low phase-shift attenuator has been designed and measured. As a result, at a center frequency (1855 MHz), the reflection-type low-phase-shift attenuator has an attenuation of 30 dB, within the limit of 3/spl deg/ phase shift and less than -17-dB reflection characteristics at both input and output ports. It also demonstrates that the performance of the reflection type low-phase shift attenuator is better than the transmission type phase-shift attenuator with the same measurement specifications.