Method and apparatus for selecting at least one desired channel utilizing a bank of vibrating micromechanical apparatus

• US 6,680,660 B2
• Filed: 01/14/2003
• Issued: 01/20/2004
• Est. Priority Date: 01/14/1999
• Status: Expired due to Term

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Nguyen, Clark T. C.
• Primary Examiner(s): Summons, Barbara
• Application Number:
  US10/342,029
• Publication Number:
  US 20030184413A1
• Time in Patent Office: 371 Days
• Field of Search: 333/133, 333/186-192, 333/197, 333/198
• US Class Current: 333/133
• CPC Class Codes: H01H 2059/0072 with stoppers or protrusions for maintaining a gap, reducing the contact area or for preventing stiction between the movable and the fixed electrode in the attracted position
• CPC Class Codes: H01H 59/0009 making use of micromechanics
• CPC Class Codes: H03H 2009/02511 Vertical, i.e. perpendicular to the substrate plane
• CPC Class Codes: H03H 2009/02519 Torsional
• CPC Class Codes: H03H 2009/02527 Combined
• CPC Class Codes: H03H 3/0078 involving adjustment of the transducing gap
• CPC Class Codes: H03H 9/02409 by application of a DC-bias voltage H03H9/02417 takes precedence
• CPC Class Codes: H03H 9/24 Constructional features of resonators of material which is not piezoelectric, electrostrictive, or magnetostrictive
• CPC Class Codes: H03H 9/2452 Free-free beam resonators
• CPC Class Codes: H03H 9/462 Microelectro-mechanical filters
• CPC Class Codes: H03H 9/465 in combination with other electronic elements
• CPC Class Codes: H03H 9/467 Post-fabrication trimming of parameters, e.g. center frequency
• CPC Class Codes: H03H 9/505 for microelectro-mechanical filters

Abstract

Several MEMS-based methods and architectures which utilize vibrating micromechanical resonators in circuits to implement filtering, mixing, frequency reference and amplifying functions are provided. For example, a method and apparatus for selecting at least one desired channel in an RF receiver subsystem is shown. One of the primary benefits of the use of such architectures is a savings in power consumption by trading power for high selectivity (i.e., high Q). Consequently, the present invention relies on the use of a large number of micromechanical links in SSI to VLSI networks to implement signal processing functions with basically zero DC power consumption.

Claims

1. A method for selecting at least one desired channel from a plurality of channels to reduce power handling requirements of circuits in a system, the method comprising:

providing a bank of micromechanical apparatus wherein each apparatus has a passband corresponding to at least one channel and each of the apparatus has an input port, an output port, and a conductive mechanical network coupling the input port and the output port such that each of the apparatus is switchable between on and off states via excitation of the respective conductive mechanical network of each apparatus;

controllably switching the bank of micromechanical apparatus to select the at least one desired channel and to substantially attentuate power outside the at least one desired channel; and

vibrating the micromechanical apparatus corresponding to the at least one desired channel.

2. The method of claim 1 wherein the conductive mechanical network is excited via application of a bias voltage.

3. The method of claim 2 herein the conductive mechanical network is an open circuit when the bias voltage is not applied.

4. In a system, a channel selector apparatus for selecting at least one desired channel while minimizing the power consumption in the rest of the system, the apparatus comprising:

a parallel bank of on/off switchable micromechanical filters wherein each of the filters has a passband which corresponds to at least one channel and wherein each of the filters has an input port, an output port, and a conductive mechanical network coupling the input port and the output port such that each filter is switchable between on and off states via excitation of the respective conductive mechanical network of each filter; and

a controller for selectively switching a desired filter of the bank of filters “

on”

while switching the rest of the filters “

off”

to thereby provide channel selection and remove interferers.

5. The apparatus of claim 4 wherein the conductive mechanical network is excited via application of a bias voltage.

6. The apparatus of claim 5 wherein the conductive mechanical network is an open circuit when the bias voltage is not applied.

7. The apparatus as claimed in claim 4 wherein each of the filters includes at least one, high-Q, micromechanical resonator.

8. The apparatus as claimed in claim 4 wherein the filters are interlinked and wherein each of the filters has an input connected to a common input and each of the filters has an output connected to a common output.

9. The apparatus as claimed in claim 4 wherein the controller includes a decoder for controlling application of an appropriate bias voltage to the desired filter.

10. The apparatus as claimed in claim 4 wherein the apparatus operates like a narrowband filter.

11. The apparatus as claimed in claim 4 wherein the apparatus operates like a highly selective, low-loss filter that is tunable from channel to channel.

12. The apparatus as claimed in claim 4 wherein each of the filters has a Q greater than 100.

13. The apparatus as claimed in claim 4 wherein each of the filters is switchable and tunable.

14. The system as claimed in claim 4 wherein the system includes an RF receiver subsystem and wherein the apparatus in an RF channel selector apparatus for selecting at least one desired RF channel.