Calibrated low loss radio frequency switch matrix

Details Calibrated low loss radio frequency switch matrix Calibrated low loss radio frequency switch matrix

1998-08-03

2001-09-25

Kizou, Hassan (Department: 2662)

Multiplex communications

Communication over free space

Repeater

C370S360000, C340S870030

Reexamination Certificate

active

06295282

ABSTRACT:

FIELD OF THE INVENTION
The invention relates generally to the field of radio frequency electronics and, more particularly, to a calibrated low loss radio frequency switch matrix.
BACKGROUND OF THE INVENTION
In a communication system which employs multiple satellite antennas which project communication beams onto the surface of the earth, a group of receive antenna beams must be switched or routed from receiving antennas to one or more available tuners. These tuners downconvert the signals from the receiving antennas in order to extract the information conveyed by the received signals. This information can represent analog or digitized voice, analog or digitized video, facsimile data, and so on. In some communication satellite architectures, as many as 50 or 100 antenna beams must be simultaneously routed to one or many tuners. Therefore, because of the requirements of the satellite system to switch between tuners and antenna beams, switch matrices are employed to perform this function. Generally, these switching matrices must operate at radio frequencies and higher.
Radio frequency switch matrices are generally embodied as large three-dimensional structures. Crossbar switches may be used at higher frequencies, but can be rendered less effective due to the need for directional couplers used to multiplex signals from one or more input pathways to one or more output pathways. Additionally, at some frequencies (such as below 3.0 GHz) their use may be impractical due to the large volume required to implement a directional coupler which operates in this frequency range. The problem is compounded in that multiple switch matrices are often required in order to meet the capacity needs of the particular communication system.
Additionally, future communication systems will demand that switch matrices be calibrated to within one dB of the desired gain in order to maintain transmit and receive beam-to-beam isolation requirements. With current radio frequency technology, it is impractical to manually align or to expect manufacturing tolerances of one dB in large switch matrices. Further, maintaining a flat frequency response over a large bandwidth can dramatically increase the cost and complexity of a radio frequency crossbar switch used in either transmit or receive communications modules.
Therefore, what is needed is an inexpensive radio frequency switch matrix capable of operating over a wide bandwidth which provides a multiplexing function without requiring a large amount of weight and power. What is also needed, is a radio frequency switch matrix that can be quickly and automatically calibrated with a minimum number of calibration coefficients.


REFERENCES:
patent: 4430732 (1984-02-01), Saga et al.
patent: 4456988 (1984-06-01), Nakagome et al.
patent: 4858225 (1989-08-01), deSantis
patent: 5430443 (1995-07-01), Mitchell
patent: 5757941 (1998-05-01), McMillen
patent: 5932936 (1999-08-01), Potthast et al.

Affiliated with

Also associated with

Rating

Calibrated low loss radio frequency 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 Calibrated low loss radio frequency switch matrix, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Calibrated low loss radio frequency switch matrix will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2471732