Active solid-state devices (e.g. – transistors – solid-state diode – Housing or package – For plural devices
Reexamination Certificate
2000-08-22
2002-02-12
Clark, Sheila V. (Department: 2815)
Active solid-state devices (e.g., transistors, solid-state diode
Housing or package
For plural devices
C257S723000, C257S728000
Reexamination Certificate
active
06346744
ABSTRACT:
The invention relates to a RF switch matrix and, more particularly, the invention relates to an integrated RF M×N switch matrix using N×N switch modules.
BACKGROUND OF THE DISCLOSURE
Switch matrices are critical components in virtually all modern communications systems, especially satellite systems. Such matrices are used principally to route up-link channels to a specific down-link channel. In some instances, switch matrices may have a “broadcast mode” in that an individual incoming signal is simultaneously routed to a number of outgoing channels for transmission.
RF switches come in a variety of configurations, the most basic being a single pole, single throw having a single RF input and a single RF output. Typically the RF signal is switched electronically with RF switching diodes or field effect transistors. Such RF switches are combined to form M×N switch matrices and are typically constructed using Monolithic Microwave Integrated Circuitry (MMIC) techniques wherein nonintersecting transmission lines, interconnections, and switch elements are integrated on a multilevel substrate using thin film processing techniques. The MMIC technique is impractical in most instances where there are numerous inputs and outputs to be switched because chip size becomes very large due to circuit complexity.
Thus, there exists a need in the art for automated production of efficient, reliable switch matrices that are able to operate in the RF frequency range.
SUMMARY OF THE INVENTION
The disadvantages associated with the prior art are overcome by forming an M×N RF switch matrix using a multilayer ceramic circuit board that accommodates M×N switch modules, each switch module being an N×N switch matrix. The ceramic structure exhibits low RF loss and the metal base functions both as a heatsink and as a RF ground. The circuit board has an M×N array of mounting sites for accepting the switch modules and contains all the necessary RF routing, bias, and control lines to interconnect the switch modules to from the M×N switch matrix.
In one embodiment of the invention, the circuit board is a multilayer ceramic structure on a metal base that is fired using a Low Temperature Ceramic Circuit on Metal (LTCC-M) process. An LTCC-M process provides for zero-shrinkage in the plane of the circuit board allowing for the fabrication of large-area boards with tight tolerances over the entire area of the board. The switch modules can be MMIC devices or can also be fabricated using an LTCC-M process. The switch modules attach to the ceramic circuit board at the mounting sites via wire-bonds or flip-chip bonds. The mounting sites are punch cavities whereby the metal base of each switch module is coupled to the metal base of the motherboard. The switch modules are interconnected by the circuit board to from an M×N switch matrix. In an alternative embodiment of the invention, the switch modules are surface mounted to the circuit board at the mounting sites.
REFERENCES:
patent: 4364044 (1982-12-01), Kusano
patent: 4605928 (1986-08-01), Georgiou
patent: 5150083 (1992-09-01), Chen et al.
patent: 5159700 (1992-10-01), Reid et al.
patent: 5227781 (1993-07-01), Ninnis
patent: 5469001 (1995-11-01), Vaillant
patent: 5473293 (1995-12-01), Chigodo et al.
patent: 5481073 (1996-01-01), Singer et al.
patent: 5491482 (1996-02-01), Dingwell et al.
patent: 5502445 (1996-03-01), Dingwell et al.
patent: 5550342 (1996-08-01), Danek et al.
patent: 5796377 (1998-08-01), Gonzalez et al.
patent: 5867060 (1999-02-01), Burkett et al.
patent: 5932936 (1999-08-01), Potthast et al.
patent: 6064127 (2000-05-01), Vaillant
patent: 0 240 805 (1987-10-01), None
Burke William J.
Clark Sheila V.
Sarnoff Corporation
LandOfFree
Integrated RF M×N switch matrix does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Integrated RF M×N switch matrix, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Integrated RF M×N switch matrix will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2951338