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Patent for Sale:

Electronic Active Filters for Telecommunications    

Active RC Electronic Biquad - Universal Self-Compensated Filters for IF-Radio Frequency Telecommunications


2° order, 3 base-stages biquad/universal continuous time analog active filters type resonant and, more particularly, active full self-compensation techniques to improve the frequency range, the stability and/or the selectivity of the filters themselves with a very low, or as if zero, cost.

These active filters techniques are the only ones that can (fully) erase effects of parasitic poles using a single resistor or an additional operational amplifier that has a functionally filtering output.

Primary Application of the Technology

These type of filters may be adopted in many electronics products, improving their performances: Telecommunications, radio systems (IF down-conversion input stage or input unit of a superheterodyne receiving system), walkie talkies, analog/mixed-signal systems, equalizers, SOC (systems on chip), measurement electronic instruments (such as oscilloscopes) and the like.

More Particulary: LF (low frequency) to IF (intermediate frequency), particulary in systems for telecommunications and just for example, in a remote reception stage system, where high filtering performances are required to receive and amplifing the signal(s) of interest only, to carry out the right transmitted information to be decoded, without using several filter stages and having system destabilization.

The Problem Solved by the Technology

This technology compensates for the parasitic poles of active filters. In particular, these filters erase the frequency parasitic effects due to the finite gain-bandwidth product of the operational amplifiers employed in the electronic filters themselves. Since these analog filters type (n-th order low-pass, high-pass, bandpass, notch, rejection band) is very used into radio receivers, the improvements carried out by this patented technology is very useful and relevant in the telecommunication electronics field.

How the Technology Solves the Problem

These active filters techniques are revolutionary, because they are the only ones in the world that (fully) extend the limited bandwidth of the operational amplifiers employed using, with new direct connections, a single resistor or an additional operational amplifier that has a functionally filtering output, and without destabilizing the filter itself.

Competitive Advantage

-Very easy to manufacture, no special components or procedures are required;
-They are the most stable (no manual compensation is needed), and the less noisy* CT single-ended analog active filters (*noise is the interference signals and the lower it is, the higher is the device fidelity);
-They are inexpensive and require less space, this means:
-A lower manufacturing cost than the other compensated filters;
-Saving power consumption and integrated chip area making more versatile, reliable the circuit(s) and longer its life. Ideal for devices that have to work in space or for long time without any human intervention, in critical enviromental conditions also.

The seller may consider selling these patents individually.

Additional Information

EXPERIMENTAL TEST: These filters have been carefully studied, go-between thousands of behaviour analysis done by computer using the P.S.P.I.C.E. simulator software, and testing dozen of prototypes.

Several types of analog CT active filters are available today, someone recently patented by great companies too using low noise balanced operational amplifiers also, but they can’t make use of the “Total Parasitic Voltage Control System” (TPVCS).

Patent Summary

U.S. Patent Classes & Classifications Covered in this listing:

Class 327: Miscellaneous Active Electrical Nonlinear Devices, Circuits, And Systems

This is the residual class for electrical devices, circuits or systems having an output not directly proportional to its input and comprising at least one component which can provide gain or can route electrical current and which device, circuit or system does not form a complete system such as is classified specifically elsewhere or a subcombination of utility only in such elsewhere classified system.

Subclass 552: Active filter
Subclass 554: Switched capacitor filter

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