US 5,349,312 A · Voltage variable attenuator

Abstract

A voltage variable attenuator is described including a quadrature hybrid coupler having an input port, an output port, a first reflective port and a second reflective port. The voltage variable attenuator further includes a first and a second impedance network, the first impedance network connected to the first reflective port of the quadrature hybrid coupler, the second impedance network connected to the second reflective port of the quadrature hybrid coupler, each impedance network including a first RF propagation network having a first end connected to the respective reflective port of the quadrature hybrid coupler. Each impedance network further includes a second end of the first RF propagation network connected to a field effect transistor having a drain electrode, a source electrode and a gate electrode, the drain electrode connected to the second end of the first RF propagation network. Completing each impedance network is a second RF propagation network having a first end connected to the source electrode and a second electrode connected to a ground through a plated via hole.

Claims13

Dependent claims

A voltage variable attenuator comprising:

(a) a quadrature hybrid coupler having an input port, an output port, a first reflective port and a second reflective port;
and
(b) an impedance network coupled to the first reflective port, the impedance network comprising:
(i) a first RF propagation network having a first end coupled to the first reflective port of the quadrature hybrid coupler and a second end;
(ii) a field effect transistor having a source electrode, a drain electrode and a gate electrode, the drain electrode coupled to the second end of the first RF propagation network;
and
(iii) a second RF propagation network having a first end coupled to the source electrode and a second electrode coupled to a ground.

4 more elements

A voltage variable attenuator comprising:

(a) means, having a first, a second, a third and a fourth port, for coupling any signal fed to the first port to the second and third port and for coupling any signals fed to the second and third port to the fourth port;
(b) first means, responsive to a control signal and connected to the second port of the coupling means, for attenuating a predetermined portion of a signal incident thereto in response to the control signal;
and
(c) second means, responsive to the control signal and connected to the third port of the coupling means, for attenuating a predetermined portion of a signal incident thereto in response to the control signal, the first and second attenuating means each attenuating a similar predetermined portion of the signal incident thereto.

1 more element

Dependencies are inferred from the claim text.

Voltage variable attenuator

Life of this patent

Voltage variable attenuator

Life of this patent

Abstract

Claims13