US5554993A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Global position determining system and method
Assignee: Panasonic Corp of North America
•
Filing: 1994-01-04
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Granted: 1996-09-10
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Expires: 2014-01-04
Abstract
Abstract A global position determining system conserves battery power in a battery powered user terminal by transmitting its approximate position initially and then inhibiting transmission of a homing beacon until a homing terminal is in the vicinity of the user terminal. After user activation, the user terminal determines its own approximate position and transmits an approximate position signal to a satellite. The satellite then relays the approximate position signal to a mobile homing terminal. After moving the mobile homing terminal toward the approximate position, an activate homing beacon command is transmitted to the user terminal. When the transmitted command is received, the homing beacon is activated. Upon activation of the homing beacon, a directional antenna of the mobile homing terminal can be oriented toward a first direction which has a strong homing beacon reception relative to other directions and moved towards that direction.
Inventors
- 👤 John W. Brickell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:09
CPC Classifications
G; G01; G01S; G01S5/00; G01S5/0009; G01S5/0018; G01S5/0027; G01S5/02; G01S5/12; G08; G08B; G08B25/00; G08B25/01; G08B25/016
Claims Analysis
Total Claims: 51
Claim 1
Independent Claim
133 words
A position determining method which uses a satellite for transmitting signals between a mobile homing terminal having a directional antenna and a user terminal having a transmitter and a homing beacon, said method comprising the steps of: generating, at the user terminal, an approximate position signal of the user terminal; transmitting the approximate position signal from the user terminal to the mobile homing terminal via the satellite; moving the mobile homing terminal toward the approximate position; transmitting an activate homing beacon command to the user terminal when the mobile homing terminal has approached the approximate position; activating the homing beacon of the user terminal in response to receipt of the activate homing beacon command; and locating the user terminal using the directional antenna of the mobile homing terminal and the activated homing beacon.
Claim 2
Dependent Claim
133 words
A position determining method which uses a satellite for transmitting signals between a mobile homing terminal having a directional antenna and a user terminal having a transmitter and a homing beacon, said method comprising the steps of: generating, at the user terminal, an approximate position signal of the user terminal; transmitting the approximate position signal from the user terminal to the mobile homing terminal via the satellite; moving the mobile homing terminal toward the approximate position; transmitting an activate homing beacon command to the user terminal when the mobile homing terminal has approached the approximate position; activating the homing beacon of the user terminal in response to receipt of the activate homing beacon command; and locating the user terminal using the directional antenna of the mobile homing terminal and the activated homing beacon.
Claim 3
Dependent Claim
78 words
A method according to claim 1 wherein the step of determining an approximate position is preceded by the following step which is performed by the satellite: transmitting satellite position data and satellite velocity data; and wherein said determining step comprises the steps of: receiving the transmitted satellite position data and satellite velocity data from the satellite; and determining an approximate position of the user terminal from the received satellite position data, satellite velocity data, and doppler shift measurements.
Claim 4
Dependent Claim
50 words
A method according to claim 1 wherein the step of transmitting an approximate position signal comprises the step of transmitting an approximate position signal from the user terminal to the satellite, from the satellite to a network control center, and from the network control center to the mobile homing terminal.
Claim 5
Dependent Claim
27 words
A method according to claim 3 wherein the approximate position signal is transmitted from the network control center to the mobile homing terminal via a base station.
Claim 6
Dependent Claim
21 words
A method according to claim 1 wherein the step of transmitting an activate homing beacon command is performed by the satellite.
Claim 7
Dependent Claim
23 words
A method according to claim 1 wherein the step of transmitting an activate homing beacon command is performed by the mobile homing terminal.
Claim 8
Dependent Claim
26 words
A method according to claim 1 wherein the step of activating the homing beacon comprises the step of activating a low power continuous wave homing beacon.
Claim 9
Dependent Claim
52 words
A method according to claim 1 wherein the step of locating the user terminal comprises the steps of: orienting the directional antenna of the mobile homing terminal in a first direction which has a strong homing beacon reception relative to other directions; and moving towards the homing beacon in the first direction.
Claim 10
Independent Claim
66 words
A method of operating a battery powered user terminal to conserve battery power during a search mission, comprising the steps of: generating an approximate position signal of the user terminal; transmitting the approximate position signal; inhibiting transmission of a homing beacon of the user terminal until receipt of an activate homing beacon command; and activating the homing beacon upon receipt of the activate homing beacon command.
Claim 11
Independent Claim
66 words
A method of operating a battery powered user terminal to conserve battery power during a search mission, comprising the steps of: generating an approximate position signal of the user terminal; transmitting the approximate position signal; inhibiting transmission of a homing beacon of the user terminal until receipt of an activate homing beacon command; and activating the homing beacon upon receipt of the activate homing beacon command.
Claim 12
Dependent Claim
48 words
A method according to claim 9 wherein the step of determining an approximate position comprises the steps of: receiving transmitted satellite position data and satellite velocity data from a satellite; and determining an approximate position from the received satellite position data, satellite velocity data, and doppler shift measurements.
Claim 13
Dependent Claim
33 words
A method according to claim 9 wherein the step of activating the homing beacon comprises the step of activating the homing beacon in response to an activate homing beacon command from a satellite.
Claim 14
Dependent Claim
35 words
A method according to claim 9 wherein the step of activating the homing beacon comprises the step of activating the homing beacon in response to an activate homing beacon command from a mobile homing terminal.
Claim 15
Dependent Claim
26 words
A method according to claim 9 wherein the step of activating the homing beacon comprises the step of activating a low power continuous wave homing beacon.
Claim 16
Independent Claim
99 words
A method of operating a mobile homing terminal having a directional antenna, in order to conserve battery power of a battery powered user terminal during a search mission, comprising the steps of: receiving an approximate position signal of the user terminal; moving the mobile homing terminal towards the approximate position based upon the received approximate position signal of the user terminal; transmitting an activate homing beacon command when the mobile homing terminal approaches the approximate position; and locating the user terminal using the directional antenna of the mobile homing terminal and the activated homing beacon of the user terminal.
Claim 17
Independent Claim
99 words
A method of operating a mobile homing terminal having a directional antenna, in order to conserve battery power of a battery powered user terminal during a search mission, comprising the steps of: receiving an approximate position signal of the user terminal; moving the mobile homing terminal towards the approximate position based upon the received approximate position signal of the user terminal; transmitting an activate homing beacon command when the mobile homing terminal approaches the approximate position; and locating the user terminal using the directional antenna of the mobile homing terminal and the activated homing beacon of the user terminal.
Claim 18
Dependent Claim
24 words
A method according to claim 14 wherein said receiving step comprises the step of receiving an approximate position signal from a network control center.
Claim 19
Dependent Claim
22 words
A method according to claim 14 wherein said receiving step comprises the step of receiving an approximate position signal from a satellite.
Claim 20
Dependent Claim
23 words
A method according to claim 14 wherein said receiving step comprises the step of receiving an approximate position signal from a base station.
Claim 21
Dependent Claim
31 words
A method according to claim 14 wherein the step of transmitting an activate homing beacon command comprises the step of transmitting an activate a low power continuous wave homing beacon command.
Claim 22
Dependent Claim
52 words
A method according to claim 14 wherein the step of locating the user terminal comprises the steps of: orienting the directional antenna of the mobile homing terminal in a first direction which has a strong homing beacon reception relative to other directions; and moving towards the homing beacon in the first direction.
Claim 23
Dependent Claim
104 words
A position determining system comprising: a mobile homing terminal; and a battery powered user terminal comprising: means for generating an approximate position signal of the user terminal; means for transmitting the approximate position signal in response to user activation, to initiate a search mission; and means, responsive to radio reception of an activate homing beacon command, for activating a homing beacon; and wherein said mobile homing terminal comprises: means for receiving an indication of said approximate position signal from said battery powered user terminal; and means, responsive to receipt of said homing beacon, for homing on said homing beacon to locate the user terminal.
Claim 24
Dependent Claim
104 words
A position determining system comprising: a mobile homing terminal; and a battery powered user terminal comprising: means for generating an approximate position signal of the user terminal; means for transmitting the approximate position signal in response to user activation, to initiate a search mission; and means, responsive to radio reception of an activate homing beacon command, for activating a homing beacon; and wherein said mobile homing terminal comprises: means for receiving an indication of said approximate position signal from said battery powered user terminal; and means, responsive to receipt of said homing beacon, for homing on said homing beacon to locate the user terminal.
Claim 25
Dependent Claim
27 words
A position determining system according to claim 20 wherein said mobile homing terminal further comprises means, responsive to user activation, for transmitting said activate homing beacon command.
Claim 26
Dependent Claim
29 words
A position determining system according to claim 20 further comprising a satellite for relaying said approximate position signal between said battery powered user terminal and said mobile homing terminal.
Claim 27
Dependent Claim
28 words
A position determining system according to claim 22 further comprising a network control center for relaying said approximate position signal between said satellite and said mobile homing terminal.
Claim 28
Dependent Claim
29 words
A position determining system according to claim 23 further comprising a base station for relaying said approximate position signal between said network control center and said mobile homing terminal.
Claim 29
Dependent Claim
37 words
A position determining system according to claim 20 wherein said means for generating the approximate position signal further comprises: means for determining the approximate position of said battery powered user terminal in response to received satellite data.
Claim 30
Dependent Claim
43 words
A position determining system according to claim 25 wherein said means for determining an approximate position comprises: means for measuring doppler shifts in said received satellite data; and means for calculating said approximate position from said satellite data and said measured doppler shifts.
Claim 31
Dependent Claim
32 words
A position determining system according to claim 21 wherein said means for transmitting said activate homing beacon command comprises means for transmitting an activate a low power continuous wave homing beacon command.
Claim 32
Dependent Claim
28 words
A position determining system according to claim 21 wherein said means for transmitting said activate homing beacon command comprises means for omnidirectionally transmitting said activate homing beacon command.
Claim 33
Dependent Claim
28 words
A position determining system according to claim 20 wherein said means for homing on said homing beacon comprises means for indicating received signal strength of said homing beacon.
Claim 34
Dependent Claim
28 words
A position determining system according to claim 20 wherein said means for homing on said homing beacon comprises means for displaying received signal strength of said homing beacon.
Claim 35
Dependent Claim
69 words
A mobile homing terminal comprising: means for receiving an indication of an approximate position signal from a battery powered user terminal; means for transmitting an activate homing beacon command to the user terminal to thereby activate a homing beacon thereof when the mobile homing terminal approaches the user terminal; and means, responsive to receipt of a homing beacon, for homing on said homing beacon to locate the user terminal.
Claim 36
Dependent Claim
69 words
A mobile homing terminal comprising: means for receiving an indication of an approximate position signal from a battery powered user terminal; means for transmitting an activate homing beacon command to the user terminal to thereby activate a homing beacon thereof when the mobile homing terminal approaches the user terminal; and means, responsive to receipt of a homing beacon, for homing on said homing beacon to locate the user terminal.
Claim 37
Dependent Claim
34 words
A mobile homing terminal according to claim 31 wherein said means for receiving an indication of an approximate position signal comprises means for receiving an indication of an approximate position signal from a satellite.
Claim 38
Dependent Claim
36 words
A mobile homing terminal according to claim 31 wherein said means for receiving an indication of an approximate position signal comprises means for receiving an indication of an approximate position signal from a network control center.
Claim 39
Dependent Claim
35 words
A mobile homing terminal according to claim 31 wherein said means for receiving an indication of an approximate position signal comprises means for receiving an indication of an approximate position signal from a base station.
Claim 40
Dependent Claim
32 words
A mobile homing terminal according to claim 31 wherein said means for transmitting an activate homing beacon command comprises means for transmitting an activate a low power continuous wave homing beacon command.
Claim 41
Dependent Claim
28 words
A mobile homing terminal according to claim 31 wherein said means for transmitting an activate homing beacon command comprises means for omnidirectionally transmitting said activate homing beacon command.
Claim 42
Dependent Claim
28 words
A mobile homing terminal according to claim 31 wherein said means for homing on said homing beacon comprises means for indicating received signal strength of said homing beacon.
Claim 43
Dependent Claim
28 words
A mobile homing terminal according to claim 31 wherein said means for homing on said homing beacon comprises means for displaying received signal strength of said homing beacon.
Claim 44
Dependent Claim
54 words
A battery powered user terminal comprising: means for generating an approximate position signal for the user terminal; means for transmitting the approximate position signal in response to user activation, to initiate a search mission; a homing beacon; and means for activating said homing beacon responsive to radio reception of an activate homing beacon command.
Claim 45
Dependent Claim
54 words
A battery powered user terminal comprising: means for generating an approximate position signal for the user terminal; means for transmitting the approximate position signal in response to user activation, to initiate a search mission; a homing beacon; and means for activating said homing beacon responsive to radio reception of an activate homing beacon command.
Claim 46
Dependent Claim
29 words
A battery powered user terminal according to claim 39 wherein said means for transmitting an approximate position signal comprises means for transmitting an approximate position signal to a satellite.
Claim 47
Dependent Claim
32 words
A battery powered user terminal according to claim 39 wherein said means for generating the approximate position signal further comprises means for determining an approximate position in response to received satellite data.
Claim 48
Dependent Claim
44 words
A battery powered user terminal according to claim 41 wherein said means for determining an approximate position comprises: means for measuring doppler shifts in said received satellite data; and means for calculating said approximate position from said satellite data and said measured doppler shifts.
Claim 49
Dependent Claim
28 words
A battery powered user terminal according to claim 39 wherein said means for activating a homing beacon comprises means for activating a low power continuous wave homing beacon.
Claim 50
Dependent Claim
35 words
A battery powered user terminal according to claim 39 wherein said means for activating a homing beacon is responsive to receipt of an activate homing beacon command from a satellite for activating the homing beacon.
Claim 51
Dependent Claim
36 words
A battery powered user terminal according to claim 39 wherein said means for activating a homing beacon is responsive to receipt of an activate homing beacon command from a homing terminal for activating the homing beacon.
References Cited (Backward Citations)
US3063048A
Cited
US3440635A
Cited
US3876980A
Cited
US4045799A
Cited
US4177466A
Cited
US4240079A
Cited
US4596988A
Cited
US4965586A
Cited
US4908629A
Cited
US4819053A
Cited
US4740792A
Cited
US5021794A
Cited
US5252963A
Cited
US5119102A
Cited
US5111209A
Cited
US5043736A
Cited
US5043736B1
Cited
US5115223A
Cited
US5202829A
Cited
US5223844A
Cited
US5223844B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-09-10 | 2000-03-11 | 2000-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-09-10 | 2004-03-11 | 2004-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-09-10 | 2008-03-11 | 2008-09-10 | $7700.00 | Window Closed / Lapsed |