US5689248A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods for reducing power consumption in remote sensing applications
Assignee: Gas Technology Institute
•
Filing: 1994-12-15
•
Granted: 1997-11-18
•
Expires: 2014-12-15
Abstract
Abstract The methods of this invention reduce the amount of power consumed by a remotely positioned (i.e. downhole) sensor/transmitter used in applications such as well bore telemetry. The method involves the sensing of physical characteristics such as pressure and/or temperature to generate a first absolute value than is transmitted to a surface receiver located at the earth's surface. At a later time (or period) the physical characteristic is again sensed to generate a second absolute value that is subtracted from the first absolute value to generate a difference. If the difference is significant (i.e., greater than a predetermined value), the difference will be transmitted to the surface receiver. Because the difference will generally have fewer bits of data than the absolute data, less data can be transmitted so that battery power is conserved in the remote sensor/transmitter. In the event that the difference is not significant, even fewer bits need to be transmitted by the remote sensor/transmitter. Another method uses the fact that temperature is a more slowly changing phenomenon than pressure, and transmits data in frame formats constructed so that the transmission bit rate of sensed pressure data is higher than the transmission rate of sensed temperature data. In another method of this invention, the remote sensor/transmitter is programmed into a sleep state in which the remote sensor/transmitter consumes no appreciable battery power, for example, while being run down a well bore. The remote sensor/transmitter then transitions from the sleep state to the operation state after the expiration of a predetermined time period or by transmission of a control signal thereto.
Inventors
- 👤 Farhad Esfahani
- 👤 James Lloyd Davis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:39
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/12; E21B47/125; G; G01; G01V; G01V3/00; G01V3/18; G01V3/34
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
81 words
A method comprising the steps of: sensing a first amount of a physical characteristic at a first time; sensing a second amount of a the physical characteristic subsequent to said first time; storing said second amount of said physical characteristic as an absolute measurement; determining a difference between the first and second amounts; choosing a data transmission frame based upon said difference; transmitting said difference in a format of said frame; and simultaneously transmitting said absolute measurement sequentially in said frame.
Claim 2
Independent Claim
81 words
A method comprising the steps of: sensing a first amount of a physical characteristic at a first time; sensing a second amount of a the physical characteristic subsequent to said first time; storing said second amount of said physical characteristic as an absolute measurement; determining a difference between the first and second amounts; choosing a data transmission frame based upon said difference; transmitting said difference in a format of said frame; and simultaneously transmitting said absolute measurement sequentially in said frame.
Claim 3
Dependent Claim
46 words
A method as claimed in claim 1, wherein said step of choosing a data transmission frame based upon said difference further comprises the steps of: comparing the difference with a predetermined value to generate a result; and choosing said data transmission frame based on said result.
Claim 4
Dependent Claim
13 words
A method as claimed in claim 1, wherein the physical characteristic is pressure.
Claim 5
Dependent Claim
13 words
A method as claimed in claim 1, wherein the physical characteristic is temperature.
Claim 6
Independent Claim
109 words
A method comprising the steps of: sensing a first amount of a physical characteristic at a first time; sensing a second amount of the physical characteristic at a second time later than the first time; storing said second amount of said physical characteristic as an absolute measurement; extrapolating a third amount of the physical characteristic corresponding to the second time, based on the first amount and the first time; determining a difference between the second and third amounts; choosing a data transmission frame based on said difference; transmitting said difference in the format of said frame; and transmitting said absolute measurement sequentially in said frame simultaneously with said difference.
Claim 7
Independent Claim
109 words
A method comprising the steps of: sensing a first amount of a physical characteristic at a first time; sensing a second amount of the physical characteristic at a second time later than the first time; storing said second amount of said physical characteristic as an absolute measurement; extrapolating a third amount of the physical characteristic corresponding to the second time, based on the first amount and the first time; determining a difference between the second and third amounts; choosing a data transmission frame based on said difference; transmitting said difference in the format of said frame; and transmitting said absolute measurement sequentially in said frame simultaneously with said difference.
Claim 8
Dependent Claim
41 words
The method as claimed in claim 5, further comprising the step of comparing the difference with a predetermined value to generate a result, said step of choosing a data transmission frame based on said difference being performed based on said result.
Claim 9
Dependent Claim
13 words
A method as claimed in claim 5, wherein the physical characteristic is pressure.
Claim 10
Dependent Claim
13 words
A method as claimed in claim 5, wherein the physical characteristic is temperature.
Claim 11
Independent Claim
94 words
A method for minimizing transmission power consumption of a remote apparatus, comprising the steps of: taking a first measurement of at least one physical characteristic; taking a second measurement of said physical characteristic subsequent to said first measurement; comparing a difference between said first measurement and said second measurement with a predetermined value; creating a transmission frame based on said difference, the length of said frame substantially equaling the length necessary to transmit said difference, wherein unnecessary consumption of transmission power is avoided; and transmitting said difference in the form of said transmission frame.
Claim 12
Independent Claim
94 words
A method for minimizing transmission power consumption of a remote apparatus, comprising the steps of: taking a first measurement of at least one physical characteristic; taking a second measurement of said physical characteristic subsequent to said first measurement; comparing a difference between said first measurement and said second measurement with a predetermined value; creating a transmission frame based on said difference, the length of said frame substantially equaling the length necessary to transmit said difference, wherein unnecessary consumption of transmission power is avoided; and transmitting said difference in the form of said transmission frame.
Claim 13
Dependent Claim
23 words
The method of claim 9, further comprising the step of sequentially transmitting an absolute measurement of said physical characteristic simultaneously with said difference.
Claim 14
Dependent Claim
23 words
The method of claim 10, further comprising the steps of: measuring said physical characteristic transmitting an absolute measurement of said physical characteristic periodically.
Claim 15
Dependent Claim
33 words
The method of claim 9, wherein said step of taking said first measurement, further comprises the steps of: taking a first measurement of a pressure; and taking a first measurement of a temperature.
Claim 16
Dependent Claim
49 words
The method of claim 12, wherein said step of taking said second measurement, further comprises the steps of: taking a second measurement of said pressure subsequent to said first measurement of said pressure; and taking a second measurement of said temperature subsequent to said first measurement of said temperature.
Claim 17
Dependent Claim
56 words
The method of claim 13, wherein said step of comparing said difference further comprises the steps of: comparing a difference between said first and second measurements of said pressure with a predetermined change in pressure value; and comparing a difference between said first and second measurements of said temperature with a predetermined change in temperature value.
Claim 18
Dependent Claim
57 words
The method of claim 14, wherein the step of creating said transmission frame further includes the step of creating a word including a parity bit, a sign bit for said difference in pressure, a plurality of bits for the magnitude of said difference in pressure, and a sequence bit to sequentially transmit absolute pressure and temperature data.
Claim 19
Dependent Claim
77 words
The method of claim 14, wherein the step of creating said transmission frame further includes the step of creating a word including a parity bit, a sign bit for said difference in pressure, a plurality of bits for the magnitude of said difference in pressure, a sign bit for said difference in temperature, a plurality of bits for the magnitude of said difference in temperature and a sequence bit to sequentially transmit absolute pressure and temperature data.
Claim 20
Dependent Claim
37 words
The method of claim 14, wherein the step of creating said transmission frame further includes the step of creating a word including a parity bit and a sequence bit to sequentially transmit absolute pressure and temperature data.
Claim 21
Dependent Claim
57 words
The method of claim 14, wherein the step of creating said transmission frame further includes the step of creating a word including a parity bit, a sign bit for said difference in temperature, a plurality of bits for the magnitude of said difference in temperature and a sequence bit to sequentially transmit absolute pressure and temperature data.
Claim 22
Independent Claim
51 words
A method for minimizing transmission power consumption of a remote apparatus, comprising the steps of: determining an absolute pressure and an absolute temperature; determining a change in a pressure and a change in a temperature; transmitting a plurality of frames of variable length depending upon the change in pressure and temperature.
Claim 23
Independent Claim
51 words
A method for minimizing transmission power consumption of a remote apparatus, comprising the steps of: determining an absolute pressure and an absolute temperature; determining a change in a pressure and a change in a temperature; transmitting a plurality of frames of variable length depending upon the change in pressure and temperature.
Claim 24
Dependent Claim
30 words
The method of claim 19, further comprising the steps of: transmitting said absolute pressure periodically in a single frame; and transmitting said absolute temperature sequentially within said plurality of frames.
Claim 25
Dependent Claim
27 words
The method of claim 20, wherein said step of transmitting said plurality of frames further includes the step of transmitting a frame comprising sequential absolute temperature data.
Claim 26
Dependent Claim
32 words
The method of claim 20, wherein said step of transmitting said plurality of frames further includes the step of transmitting a frame comprising said change in pressure and sequential absolute temperature data.
Claim 27
Dependent Claim
32 words
The method of claim 20, wherein said step of transmitting said plurality of frames further includes the step of transmitting a frame comprising said change in temperature and sequential absolute temperature data.
Claim 28
Dependent Claim
36 words
The method of claim 20, wherein said step of transmitting said plurality of frames further includes the step of transmitting a frame comprising said change in pressure, said change in temperature and sequential absolute temperature data.
Claim 29
Dependent Claim
24 words
The method of claim 19, further comprising the step of transmitting said absolute pressure and said absolute temperature sequentially within said plurality of frames.
Claim 30
Dependent Claim
23 words
The method of claim 25, wherein said step of transmitting said plurality of frames further includes a frame comprising said change in pressure.
Claim 31
Dependent Claim
23 words
The method of claim 25, wherein said step of transmitting said plurality of frames further includes a frame comprising said change in temperature.
Claim 32
Dependent Claim
28 words
The method of claim 25, wherein said step of transmitting said plurality of frames further includes a frame comprising said change in pressure and said change in temperature.
References Cited (Backward Citations)
US2507351A
Cited
US3771118A
Cited
US3863203A
Cited
US4012712A
Cited
US4468665A
Cited
US4513403A
Cited
US4686625A
Cited
US4593559A
Cited
US4665398A
Cited
US4663628A
Cited
US4709234A
Cited
US4855732A
Cited
US4995058A
Cited
US4903245A
Cited
US5142472A
Cited
US5187473A
Cited
US5511037A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-11-17 | 2001-05-19 | 2001-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-11-17 | 2005-05-19 | 2005-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-11-17 | 2009-05-19 | 2009-11-18 | $7700.00 | Window Closed / Lapsed |