Siemens Telecommunicazioni S.p.a.

Gte Telecomunicazioni S.p.a.

Siemens Telecomunicazioni S.p.a.

Franco Marconi

Nicolo De Stena

A comb-line band-pass filter with circular cross section is made up of internal rods constituting the resonators of the filter and brought to resonance by the use of tuning screws and alternating with coupling screws. In the filter the rods are inserted in such a manner that each one is rotated in relation to the preceding one by an angle of 0.degree.&lt;.alpha.&lt;90.degree. while the coupling screws are placed at an intermediate angle. For equal electrical characteristics the length of the filter is also a function of the rotation angle of the rods.

Comb-line band-pass filters in the microwave field

To an output terminal of a hybrid circuit with output signals mutually phase shifted 90 degrees is connected a half-wave line section while to the second output terminal is connected a low attenuation filtering network having a phase characteristic which is -90 degrees at the center frequency and varies with the frequency like a half-wave line section.

Wideband microwave hybrid circuit with in-phase or phase-inverted output

A pin diode variable attenuator featuring decouping values higher than those achievable using the technique used so far, is described. This result has been achieved by implementing the line sections which the pin diodes are connected to with a characteristic impedance different than the characteristic impedance input and output to/from the attenuator.

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Monza, Italy

Franco Marconi