Patent US4249174A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4249174A Expired / Lapsed US ⏱️ 0.0 years remaining

Aircraft weather radar system

Assignee: Honeywell Inc
•
Filing: 1979-05-31
•
Granted: 1981-02-03
•
Expires: 1999-05-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A low cost airborne weather radar system suitable for mounting in the wing of a single engine aircraft. The radar antenna is a truncated parabolic dish. The receiver/transmitter, relative to parameters used in a conventional receiver/transmitter operates at relatively small peak transmitter power with a relatively long transmitter pulsewidth which, in turn, is matched to the receiver bandwidth. The relatively small peak power allows for acceptable range performance due to the relatively larger pulse width. Further, the receiver/transmitter assembly is significantly reduced in size so as to facilitate location in an aircraft wing and be thereby directly connected to the antenna to eliminate range reducing intercabling losses.

Inventors

  • 👤 George A. Lucchi
  • 👤 Ramon H. Aires

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 08:08
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/95; G01S13/953; H; H01; H01Q; H01Q1/00; H01Q1/27; H01Q1/28; H01Q1/286; H01Q1/287; Y; Y02; Y02A; Y02A90/00; Y02A90/10

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 229 words
In an airborne weather radar system of the type comprising an antenna means, an indicator means, and receiver/transmitter (R/T) means, said R/T means comprising a modulator adapted to produce periodic bias pulses of a predetermined time duration, means responsive to each bias pulse for producing a radio frequency signal of a given peak power and of time duration corresponding to said predetermined time duration, said antenna means being responsive to said radio frequency signal for radiating said signal and for receiving return signals, said R/T also comprising local oscillator means for producing a local oscillator signal, means for subtractively mixing said return signals and said local oscillator signal for producing an intermediate frequency (IF) signal, and amplifying means responsive to said IF signal for producing a signal which, as a function of time, represents the strength of said return signals, said amplifying means having a bandwidth which is a predetermined function of said time duration, wherein the improvement comprises: (a) said means producing said radio frequency signal producing said radio frequency signal having a peak power not in excess of 2000 watts; and (b) said modulator producing pulses of time duration not less than 8 microseconds; and (c) said amplifier means adapted to have a bandwidth not greater than 1.5 divided by said modulator pulse time duration, said bandwidth and said time duration being in hertz and seconds, respectively.
Claim 2
Dependent Claim 229 words
In an airborne weather radar system of the type comprising an antenna means, an indicator means, and receiver/transmitter (R/T) means, said R/T means comprising a modulator adapted to produce periodic bias pulses of a predetermined time duration, means responsive to each bias pulse for producing a radio frequency signal of a given peak power and of time duration corresponding to said predetermined time duration, said antenna means being responsive to said radio frequency signal for radiating said signal and for receiving return signals, said R/T also comprising local oscillator means for producing a local oscillator signal, means for subtractively mixing said return signals and said local oscillator signal for producing an intermediate frequency (IF) signal, and amplifying means responsive to said IF signal for producing a signal which, as a function of time, represents the strength of said return signals, said amplifying means having a bandwidth which is a predetermined function of said time duration, wherein the improvement comprises: (a) said means producing said radio frequency signal producing said radio frequency signal having a peak power not in excess of 2000 watts; and (b) said modulator producing pulses of time duration not less than 8 microseconds; and (c) said amplifier means adapted to have a bandwidth not greater than 1.5 divided by said modulator pulse time duration, said bandwidth and said time duration being in hertz and seconds, respectively.
Claim 3
Dependent Claim 20 words
The combination as set forth in claim 1, wherein said antenna means comprises an antenna reflecting dish elongated in shape.
Claim 4
Dependent Claim 18 words
The combination as set forth in claim 1, wherein said R/T and antenna are in one unitary housing.
Claim 5
Dependent Claim 26 words
The combination as set forth in claim 2 or claim 3, wherein said R/T and antenna are adapted for mounting in a wing of an aircraft.
Claim 6
Dependent Claim 206 words
In an airborne weather radar system of the type comprising an antenna means, an indicator means, and receiver/transmitter (R/T) means, said R/T means comprising a modulator adapted to produce periodic bias pulses of a predetermined time duration, means responsive to each bias pulse for producing a radio frequency signal of a given peak power and of time duration corresponding to said predetermined time duration, said antenna means being responsive to said radio frequency signal for radiating said signal and for receiving return signals, said R/T means also comprising local oscillator means for producing a local oscillator signal, means for subtractively mixing said return signals and said local oscillator signal for producing an intermediate frequency (IF) signal, and amplifying means responsive to said IF signal for producing a signal which, as a function of time represents the strength of said return signals, said amplifying means having bandwidth which is a predetermined function of said time duration, wherein the improvement comprises: an aircraft wing; and wherein said antenna means includes an antenna reflecting dish of generally elongated parabolic shape having a vertical aperture substantially shorter than the horizontal aperture mounted within said wing; and wherein said R/T is mounted in said wing is proximity to said antenna dish.
Claim 7
Dependent Claim 206 words
In an airborne weather radar system of the type comprising an antenna means, an indicator means, and receiver/transmitter (R/T) means, said R/T means comprising a modulator adapted to produce periodic bias pulses of a predetermined time duration, means responsive to each bias pulse for producing a radio frequency signal of a given peak power and of time duration corresponding to said predetermined time duration, said antenna means being responsive to said radio frequency signal for radiating said signal and for receiving return signals, said R/T means also comprising local oscillator means for producing a local oscillator signal, means for subtractively mixing said return signals and said local oscillator signal for producing an intermediate frequency (IF) signal, and amplifying means responsive to said IF signal for producing a signal which, as a function of time represents the strength of said return signals, said amplifying means having bandwidth which is a predetermined function of said time duration, wherein the improvement comprises: an aircraft wing; and wherein said antenna means includes an antenna reflecting dish of generally elongated parabolic shape having a vertical aperture substantially shorter than the horizontal aperture mounted within said wing; and wherein said R/T is mounted in said wing is proximity to said antenna dish.
Claim 8
Dependent Claim 78 words
The combination as set forth in claims 1, or 2, or 3, or 5, wherein said antenna means comprises a parabolic reflecting antenna dish having an aperture and an elongated feed with reflecting tip extending through said aperture, said feed being coupled to said R/T to receive signals therefrom to be radiated and to pass said returned signals to said R/T, said antenna means including means for pivoting said antenna dish relative to said feed to provide scanning.

References Cited (Backward Citations)

US2607009A Cited
US3009152A Cited
US3108269A Cited
US3781715A Cited
US3825928A Cited
US4092644A Cited
US4106021A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-02-03 1984-08-04 1985-02-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-02-03 1988-08-04 1989-02-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-02-03 1992-08-04 1993-02-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag