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US4525871A Expired / Lapsed US ⏱️ 0.0 years remaining

High speed optoelectronic mixer

Assignee: Massachusetts Institute of Technology
•
Filing: 1982-02-03
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Granted: 1985-06-25
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Expires: 2002-02-03
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Abstract

Abstract An electronic mixer is decribed which utilizes an optoelectronic switch formed from a semi-insulating substrate of indium phosphide doped with a deep level impurity and disposed intermediate a microstrip transmission line. One conductor of the transmission line has a small gap in its metallization. Upon illumination of the gap by laser pulses from a laser source which are absorbed near the semiconductor surface, a photo-generated electron-hole plasma forms thereby providing a conducting path across the gap. An RF signal to be mixed with a LO signal is coupled to one side of the switch. The LO signal controls the Laser source. The output of the switch is therefore the product of the RF and LO signal.

Inventors

  • 👤 Arthur G. Foyt
  • 👤 Frederick J. Leonberger
  • 👤 Richard C. Williamson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 04:35
CPC Classifications
H; H03; H03D; H03D7/00; H03D2200/00; H03D2200/0041; H03D2200/0047; H03D2200/009

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 188 words
An optoelectronic mixer comprising: (a) a substrate with planar conducting electrodes on a surface thereof; (b) one of said planar conducting electrode structures having a non-conducting space providing a non-conductive gap on said surface and adapted to be illuminated by photons from a photon source which generates a photon beam controlled by a first source of oscillatory electrical signals whereby a photo-generated plasma forms a conducting path across the gap in accordance with such oscillatory signals thereby periodically completing an electrical circuit between: (i) a second source of oscillatory electrical signals adapted to be coupled to one side of said electrode and (ii) a utilization device adapted to be coupled to another of said conducting electrodes; (c) the product of said first and second oscillatory signals being thereby coupled to said load; (d) and wherein the photon source is a laser which is biased so that the intensity of the photon beam produced by the laser varies in a linear fashion throughout its operating range such that the mixer is operated in the bilinear mode such that the first and second signals are mixed in a linear fashion.
Claim 2
Dependent Claim 188 words
An optoelectronic mixer comprising: (a) a substrate with planar conducting electrodes on a surface thereof; (b) one of said planar conducting electrode structures having a non-conducting space providing a non-conductive gap on said surface and adapted to be illuminated by photons from a photon source which generates a photon beam controlled by a first source of oscillatory electrical signals whereby a photo-generated plasma forms a conducting path across the gap in accordance with such oscillatory signals thereby periodically completing an electrical circuit between: (i) a second source of oscillatory electrical signals adapted to be coupled to one side of said electrode and (ii) a utilization device adapted to be coupled to another of said conducting electrodes; (c) the product of said first and second oscillatory signals being thereby coupled to said load; (d) and wherein the photon source is a laser which is biased so that the intensity of the photon beam produced by the laser varies in a linear fashion throughout its operating range such that the mixer is operated in the bilinear mode such that the first and second signals are mixed in a linear fashion.
Claim 3
Dependent Claim 11 words
The apparatus of claim 1 wherein the substrate is indium phosphide.
Claim 4
Dependent Claim 28 words
The apparatus of claim 1 wherein the substrate is subjected to proton bombardment at an energy level in the range of 10-1000 keV to enhance photon response time.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-06-24 1988-12-24 1989-06-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-06-24 1992-12-24 1993-06-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-06-24 1996-12-24 1997-06-25 $7700.00 Window Closed / Lapsed

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