Superconducting microwave frequency selective filter system

• US 5,244,869 A
• Filed: 10/23/1990
• Issued: 09/14/1993
• Est. Priority Date: 10/23/1990
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Corporation
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Billing, John F.
• Primary Examiner(s): Lee, Benny T.
• Application Number:
  US07/601,555
• Time in Patent Office: 1,057 Days
• Field of Search: 333/99 S, 333/202, 333/101, 333/132, 333/174, 455/275-278, 455/280, 370/38, 505/1, 505/700, 505/701, 505/866
• US Class Current: 505/202
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: Y10S 505/866 Wave transmission line, network, waveguide, or microwave storage device

Abstract

A superconducting microwave selective filter system having a superconducting filter connected to receive RF signals and perform filtering before the RF signals are applied to nonlinear circuitry such as receiver protectors and low noise amplifiers. A single pole n throw point switch selects a desired one of the filters to provide a receiver with a desired frequency, such as an active radar frequency. The low loss and high dynamic range of a superconducting filter permits these filters to be employed in the front end of the system before system nonlinear circuitry.

Claims

1. A superconducting microwave frequency selective filter system, comprising:

a manifold having an input for receiving input RF signals and outputs for distributing respective RF output signals;

a plurality of superconducting filters respectively having inputs connected to the respective outputs of the manifold and each filter having a corresponding output;

a plurality of receiver protetors respectively connected to corresponding outputs of ones of said superconducting filters;

a plurality of low noise amplifiers each having an input respectively connected to corresponding ones of said receiver protectors and each having a corresponding output;

a single pole, n throw point switch having respective ones of the n throw points connected to corresponding outputs of said low noise amplifiers; and

control means coupled to the single pole for connecting a selected one of the n throw points of a desired one of the said low noise amplifiers.

2. A superconducting microwave frequency selective filter system, comprising:

superconducting filter means having an input for receiving input RF signals and outputs for providing filtered RF signals, said superconducting filter means comprising;

a manifold having an input connected to said filter means input for receiving the input RF signals, and outputs for distributing each respective RF output signal; and

a plurality of superconducting filters respectively having inputs connected to the respective outputs of the manifold and each filter having a corresponding output;

wherein said filter system further comprises;

circuit means operatively connected to each output of said superconducting filter means, for processing the filtered RF signals;

selector means operatively connected to the circuit means for selectively outputting one of the processed filtered RF signals in accordance with a control signal applied thereto; and

control means operatively connected to the selector means for providing the control signal.

3. A superconducting microwave frequency selective filter system according to claim 2, wherein said selector means comprises:

a single pole, n throw point switch, operatively connected to said circuit means and having respective ones of the n throw points corresponding to ones of said processed filtered RF signal.

4. A superconducting microwave frequency selective filter system according to claim 3, wherein said circuit means is nonlinear and comprises:

a plurality of receiver protectors respectively connected to corresponding outputs of ones of said superconducting filters and limiting the filtered RF signals; and

a plurality of low noise amplifiers each having an input operatively connected to corresponding ones of said receiver protectors, and each having an output operatively connected to respective ones of the n throw points of said single pole, n throw point switch.

5. A superconducting microwave selective filter system according to claim 4, wherein each of said superconducting filters is characterized by a respective center frequency.