Patent ID: 8344807
Filing Date: 2013-01-01
Classification: H03F

Abstract:
1. A distributed amplifier having an amplification bandwidth extending from a first frequency to a second frequency higher than the first frequency, the distributed amplifier comprising: an input transmission medium having a first end and a second end and providing an input for the distributed amplifier at the first end; an output transmission medium having a first end and a second end and providing an output for the distributed amplifier at the second end; an amplifier arrangement comprising at least first and second amplifier parts connected at an input of the arrangement to the input transmission medium and at an output of the arrangement to the output transmission medium, the amplifier arrangement configured to provide at least first and second paths for an input signal from the input of the distributed amplifier to the output of the distributed amplifier; the first path being associated with a first phase change, the second path being associated with a second phase change and there being a difference between the first phase change and the second phase change; and the difference being larger than 30 degrees for frequencies in a noise suppression band overlapping with the amplification band overlapping with the amplification band so as to cause a phase difference between noise generated by the amplifier arrangement propagating along the first and second paths and destructive interference of the noise before the output of the distributed amplifier, thereby to suppress noise in the noise suppression band.