High technology microwave transistors with the minimum L-C ladder matching circuits

High technology microwave transistors are recognised with their typical performance characteristics. Nowadays, microwave technology is capable of manufacturing transistors with very low noise profile. At the same time, the maximum gain profile, accompanied by very low-level noise for each operating frequency, can be at a high level and fairly flat. This flat gain characteristics can be employed in the design of low noise, high gain broadband microwave amplifiers. A typical high technology transistor, NE329S01, is chosen for a worked example. Using the performance data sheets, the maximum gain profile, G_Tmax, is obtained for the conditions of F_req=0.46 dB and the matched input port, V_i=1. This high level and flat gain characteristic is realized by using the L-C ladder configuration with the minimum number of elements in both the input and output matching circuits. Another typical design example is made for the characteristics F_req=0.46 dB, V_i=1, G_T=10 dB within the range B=2-13 GHz, again via the minimum L-C ladder elements.