US4656481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Calibration instrument for continuous wave microwave doppler radar
Assignee: RCA Corp
•
Filing: 1984-08-02
•
Granted: 1987-04-07
•
Expires: 2004-08-02
Abstract
Abstract A calibration instrument for calibrating a continuous wave microwave doppler radar includes a piezoelectric sounder and means to energize the sounder to produce an acoustic signal to simulate motion of a body to the radar.
Inventors
- 👤 Daniel D. Mawhinney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:24
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/40; G01S7/4052; G01S7/4082; G01S7/4095
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
154 words
A calibration instrument for calibrating a continuous wave microwave doppler radar, said radar being of the type utilized to check the heart rate of a patient, said radar having an antenna means for transmitting continuous wave signals and receiving doppler shifted continuous wave signals, comprising in combination: a piezoelectric sounder producing an acoustic signal at a known frequency only when energized with an electrical signal and physically arranged in operating relationship with said antenna of said continuous wave radar; and means producing said electrical signal including means for producing a signal simulating the heart rate of a patient, said signal for alternately energizing and not energizing said piezoelectric sounder in a manner to simulate a patient heart rate for energizing said acoustic signal producing means to produce an acoustic signal which is directed toward said radar antenna whereby the acoustic signal produced by said means when energized may be used to calibrate said radar.
Claim 2
Dependent Claim
154 words
A calibration instrument for calibrating a continuous wave microwave doppler radar, said radar being of the type utilized to check the heart rate of a patient, said radar having an antenna means for transmitting continuous wave signals and receiving doppler shifted continuous wave signals, comprising in combination: a piezoelectric sounder producing an acoustic signal at a known frequency only when energized with an electrical signal and physically arranged in operating relationship with said antenna of said continuous wave radar; and means producing said electrical signal including means for producing a signal simulating the heart rate of a patient, said signal for alternately energizing and not energizing said piezoelectric sounder in a manner to simulate a patient heart rate for energizing said acoustic signal producing means to produce an acoustic signal which is directed toward said radar antenna whereby the acoustic signal produced by said means when energized may be used to calibrate said radar.
Claim 3
Dependent Claim
46 words
The combination as set forth in claim 1 wherein said means producing said electrical signal includes means for producing energy pulses for operating said piezoelectric sounder, said pulses being separated by a distance which is at least several times the width of each produced energy pulse.
References Cited (Backward Citations)
US3277477A
Cited
US3955198A
Cited
US3922572A
Cited
US4037121A
Cited
US4005424A
Cited
US4180816A
Cited
US4163234A
Cited
US4168502A
Cited
US4513748A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-06 | 1990-10-06 | 1991-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-06 | 1994-10-06 | 1995-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-06 | 1998-10-06 | 1999-04-07 | $7700.00 | Window Closed / Lapsed |