Patent US3594801A successfully refreshed from Google Patents.
US3594801A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direction finder
Assignee: Individual
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Filing: 1969-07-15
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Granted: 1971-07-20
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Expires: 1989-07-15
Abstract
Abstract The present invention relates to direction finding apparatus for determining the direction and/or distance to a transmitter by moving a blocking antenna between a receiving antenna and a transmitter, physically to block energy radiated to the receiving antenna from the transmitter. The receiving antenna is connected to a receiver which applies energy in accordance with the received signal to a control circuit connected to drive a motor which moves the blocking antenna until it blocks the energy path from the transmitter. The control circuit is simply a null seeking circuit to stop the motor when the received signal is at a null thereby aligning the two antennas in the direction of the transmitter. Two or more pairs of such antennas and associated apparatus will determine distance to the transmitter if the spacing between the pairs is known because the included angles are measured. Further, by orienting the antennas in a direction substantially parallel with the earth''s surface, the apparatus can be used to follow a glide path for aircraft.
Inventors
- 👤 John M Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:40
CPC Classifications
G; G01; G01S; G01S11/00; G01S11/02; G01S11/04; G01S1/00; G01S1/02
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
88 words
Direction finding apparatus for determining the direction to a transmitter comprising a frame; a pair of antennas; means supporting the antennas from tHe frame for relative movement; means for moving one antenna relative to the other to a position to block radiated transmitter energy from reaching said other antenna; a receiver connected to said other antenna; a null seeking control circuit responsive to output energy from said receiver; and motor means responsive to the null seeking circuit to drive the means for moving one antenna to said position.
Claim 2
Dependent Claim
88 words
Direction finding apparatus for determining the direction to a transmitter comprising a frame; a pair of antennas; means supporting the antennas from tHe frame for relative movement; means for moving one antenna relative to the other to a position to block radiated transmitter energy from reaching said other antenna; a receiver connected to said other antenna; a null seeking control circuit responsive to output energy from said receiver; and motor means responsive to the null seeking circuit to drive the means for moving one antenna to said position.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 further comprising impedance means matching the impedance of said one antenna connected to terminate said one antenna to dissipate received energy as heat.
Claim 4
Dependent Claim
38 words
The apparatus of claim 2 wherein the means supporting the antennas for relative movement comprises a platform adapted to rotate around said other antenna and to carry said one antenna in a circular path about the other antenna.
Claim 5
Dependent Claim
40 words
The apparatus of claim 3 further comprising indicia means responsive to movement of said one antenna to indicate the direction of alignment of said antennas when the one antenna is in said position thereby indicating the direction to the transmitter.
Claim 6
Dependent Claim
30 words
The apparatus of claim 4 further comprising means independently operable to energize the motor means apart from the null seeking circuit to drive the one antenna out of said position.
Claim 7
Dependent Claim
34 words
The apparatus of claim 2 further comprising mounting means for orienting the antennas generally parallel to the earth''s surface to determine the glide path direction to said transmitter from positions above the earth''s surface.
Claim 8
Independent Claim
68 words
The method of determining the direction to a transmitter comprising the steps of: disposing a receiving antenna and a blocking antenna in parallel orientation; deriving energy from the transmitter via the receiving antenna to move the blocking antenna to a position between the transmitter and the receiving antenna to block said energy; and indicating the direction of alignment of the antennas to determine the direction to the transmitter.
Claim 9
Independent Claim
68 words
The method of determining the direction to a transmitter comprising the steps of: disposing a receiving antenna and a blocking antenna in parallel orientation; deriving energy from the transmitter via the receiving antenna to move the blocking antenna to a position between the transmitter and the receiving antenna to block said energy; and indicating the direction of alignment of the antennas to determine the direction to the transmitter.
Claim 10
Dependent Claim
74 words
Apparatus for determining the direction to a transmitter comprising a receiving antenna and a blocking antenna; means mounting the antennas in parallel orientation and for relative movement; means deriving energy from the transmitter via the receiving antenna to move the blocking antenna to a position between the transmitter and receiving antenna to block said energy; and means for indicating the direction of alignment of the antennas from the receiving antenna through the blocking antenna.
Claim 11
Dependent Claim
74 words
Apparatus for determining the direction to a transmitter comprising a receiving antenna and a blocking antenna; means mounting the antennas in parallel orientation and for relative movement; means deriving energy from the transmitter via the receiving antenna to move the blocking antenna to a position between the transmitter and receiving antenna to block said energy; and means for indicating the direction of alignment of the antennas from the receiving antenna through the blocking antenna.
Claim 12
Dependent Claim
105 words
The apparatus of claim 8 for determining distance to the transmitter further comprising a second receiving antenna and a second blocking antenna; second means mounting the antennas in parallel orientation for relative movement and at a distance from the first mentioned receiving and blocking antennas; second means deriving energy from the transmitter via the second receiving antenna to move the second blocking antenna to a position between the transmitter and the second receiving antenna to block the energy to the second receiving antenna; and means for indicating the direction of alignment of the second antennas from the second receiving antenna through the second blocking antenna.
Claim 13
Dependent Claim
20 words
The apparatus of claim 8 further comprising means connected to the blocking antenna characterized by impedance matching the antenna impedance.
Claim 14
Dependent Claim
83 words
Apparatus for determining the direction to a transmitter comprising a receiving antenna and blocking means; means mounting the antenna and the blocking means for relative movement; means deriving energy from the transmitter via the receiving antenna to move the blocking means to a position determined by an unique response at the energy deriving means; and means for indicating the direction of alignment of the blocking means relative to the receiving antenna from the receiving antenna through the blocking means when in said position.
Claim 15
Dependent Claim
83 words
Apparatus for determining the direction to a transmitter comprising a receiving antenna and blocking means; means mounting the antenna and the blocking means for relative movement; means deriving energy from the transmitter via the receiving antenna to move the blocking means to a position determined by an unique response at the energy deriving means; and means for indicating the direction of alignment of the blocking means relative to the receiving antenna from the receiving antenna through the blocking means when in said position.
References Cited (Backward Citations)
US2425387A
Cited
US2492354A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |