Filters for mobile communication systems are currently relying on micro-scale frequency-trimmed piezoelectric resonators. Since modern radios operate in a wide range of the radio frequency (RF) spectrum, hundreds of resonators can be found on a single mobile radio. Frequency trimming often requires technological challenges, resulting in expensive fabrication processes for each of these filters. As the RF spectrum moves up to higher frequencies, these processes will become even more challenging and the need for new filtering solutions will become a top priority. 
Technology Overview
This invention proposes a novel RF filter architecture that relies on a single frequency resonator per band. The circuit is composed of N identical parallel blocks, each one consisting of a one-port resonator and two switches connected to the resonators on a common node, and to the RF ports on the other node. The performances of these new filters are comparable with the current ones, but without the need for frequency trimming at the fabrication level. These new filters are capable of live reconfiguration, as they can exhibit bandpass and bandstop operation by controlling a signal inside the circuitry. This re-programmable nature is of crucial interest, as the bandstop operation is needed for safe operation when the radio channel is not operating.
- Frequency trimming for the same band filters is solved with simple architecture, resulting in cheaper filters
- High RF filtering performances are achieved with small resonators, with lower area consumption and improved out of band rejection in a single cell
- Temperature sensitivity does not suffer from temperature-induced drift from different frequencies resonator
- Active and real-time reconfiguration between bandpass and bandstop filter can improve the rejection of close band interferers in multichannel radios
- Reconfigurable radio front ends 
- Mobile communication circuits 
- Millimeter Wave mobile devices
- License
- Partnering
- Research collaboration
Patent Information:
For Information, Contact:
Mark Saulich
Associate Director of Commercialization
Northeastern University
Giuseppe Michetti
Matteo Rinaldi
Millimeter Wave Spectrum
RF (Radio Frequency)