Attenuation compensation in distributed amplifier design

Design improvements in distributed amplifiers for optical receiver front ends

“…Moreover, output impedance is higher in the cascode pair than in the common-source FET, supplying higher output currents when loaded on a 50⍀ drain line. The former characteristics account for wider bandwidths, and the latter for higher gains [2,3]. The proposed front-end circuit topology consists of a three-section distributed amplifier, with each section containing a cascode pair with two FET of 4 ϫ 60 m gate periphery by the Alenia-Marconi System's 0.5-m GaAs MESFET technology process.…”

A new negative resistance circuit and an application for loss compensation in a distributed amplifier

“…Therefore, the upper frequency limit of a CDA is always lower than the cut-off frequency of the artificial line [3].…”

“…2 ) causes a shunt conductance at the input of the active device, which increases rapidly with frequency and causes increased attenuation with frequency in the gate-line. This shunt conductance at high frequency region can be approximated as [3]:…”

“…Other interesting application of NR circuits has been presented for loss compensation in a conventional distributed amplifier (CDA) [3]. A conventional distributed amplifier employs two artificial transmission lines that show a low-pass filter characteristic.…”

“…A negative resistance circuit has been presented previously in the literature in order to compensate a CDA for the gate line losses [3]. This circuit uses an FET in the common-gate configuration, the drain port of which offers NR behavior.…”