Milestone-Proposal:LORAN: Difference between revisions
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LORAN first signal began transmissions during the summer 1941. New LORAN transmitting stations were added around the Atlantic coast throughout WW2 and the continental United States. The LORAN-C system became obsolete, replaced by GPS navigation system and the LORAN system was terminated in a special ceremony orchestrated by USGC Washington headquarters in 8 February 2010.theHow the LORAN project was initiated, organized and managed is very interested, if not note worthy. | |||
Rapid construction under extreme weather conditions. System operation by operators from different nations: US, Canada and Denmark. Collaborative effort. MIT Lab was initially responsible for the entire program, but under close hands-on direction of the USCG. USGC's role increased. | Rapid construction under extreme weather conditions. System operation by operators from different nations: US, Canada and Denmark. Collaborative effort. MIT Lab was initially responsible for the entire program, but under close hands-on direction of the USCG. USGC's role increased. | ||
This was a completely successful American project, completed under trying time, progressing during wartime conditions without major false starts There was an exchange of radio engineering technology with the British GEE radio navigation but this is believed to have been minimal and had more to do with RAF bombers having the capability to accompanied two different size of receivers in the cockpit. | This was a completely successful American project, completed under trying time, progressing during wartime conditions without major false starts There was an exchange of radio engineering technology with the British GEE radio navigation but this is believed to have been minimal and had more to do with RAF bombers having the capability to accompanied two different size of receivers in the cockpit. | ||
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A LORAN network with only two stations cannot provide meaningful navigation information as the 2-dimensional position of the receiver cannot be fixed due to the phase ambiguities in the system and lack of an outside phase reference. | A LORAN network with only two stations cannot provide meaningful navigation information as the 2-dimensional position of the receiver cannot be fixed due to the phase ambiguities in the system and lack of an outside phase reference. | ||
A second application of the same principle must be used, based on the time difference of a different pair of stations. In practice, one of the stations in the second pair also may be—and frequently is—in the first pair. In simple terms, this means signals must be received from at least three transmitters to pinpoint the receiver's location. By determining the intersection of the two hyperbolic curves identified by this method, a geographic fix can be determined. | A second application of the same principle must be used, based on the time difference of a different pair of stations. In practice, one of the stations in the second pair also may be—and frequently is—in the first pair. In simple terms, this means signals must be received from at least three transmitters to pinpoint the receiver's location. By determining the intersection of the two hyperbolic curves identified by this method, a geographic fix can be determined. | ||
L | L | ||
LORAN-C was originally developed to provide radionavigation service for U.S. coastal waters & was later expanded to include complete coverage of the continental U.S. as well as most of Alaska. Twenty-four U.S. LORAN-C stations work in partnership with Canadian and Russian stations to provide coverage in Canadian waters and in the Bering Sea. They system provides better than 0.25 nautical mile absolute accuracy for suitably equipped users within the published areas. and provides navigation, location, and timing services for both civil and military air, land and marine users. It is approved as an en route supplemental air navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule (VFR) operations. The LORAN-C system serves the 48 continental states, their coastal areas, and parts of Alaska. Dedicated Coast Guard men and women have done an excellent job running and maintaining the LORAN-C signal for 52 years. It is a service and mission of which the entire Coast Guard can be proud. | LORAN-C was originally developed to provide radionavigation service for U.S. coastal waters & was later expanded to include complete coverage of the continental U.S. as well as most of Alaska. Twenty-four U.S. LORAN-C stations work in partnership with Canadian and Russian stations to provide coverage in Canadian waters and in the Bering Sea. They system provides better than 0.25 nautical mile absolute accuracy for suitably equipped users within the published areas. and provides navigation, location, and timing services for both civil and military air, land and marine users. It is approved as an en route supplemental air navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule (VFR) operations. The LORAN-C system serves the 48 continental states, their coastal areas, and parts of Alaska. Dedicated Coast Guard men and women have done an excellent job running and maintaining the LORAN-C signal for 52 years. It is a service and mission of which the entire Coast Guard can be proud. | ||
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The Coast Guard published a Federal Register notice on Jan. 7, 2010, regarding its intention to terminate transmission of the LORAN-C signal Feb. 8, 2010. A LORAN Programmatic Environmental Impact Statement Record of Decision stating that the environmentally preferred alternative is to decommission the LORAN-C Program and terminate the North American LORAN-C signal was http://www.navcen.uscg.gov/loran/default.htmpublished in the Federal Register on Jan. 7, 2010.
| The Coast Guard published a Federal Register notice on Jan. 7, 2010, regarding its intention to terminate transmission of the LORAN-C signal Feb. 8, 2010. A LORAN Programmatic Environmental Impact Statement Record of Decision stating that the environmentally preferred alternative is to decommission the LORAN-C Program and terminate the North American LORAN-C signal was http://www.navcen.uscg.gov/loran/default.htmpublished in the Federal Register on Jan. 7, 2010.
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USCG announces LORAN-C termination | USCG announces LORAN-C termination | ||
REFERENCES | REFERENCES | ||
JA Pierce, "An Introduction to Loran", IEEE AES Magazine 1990 (attached) | JA Pierce, "An Introduction to Loran", IEEE AES Magazine 1990 (attached) | ||
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http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | http://www.uscg.mil/History/STATIONS/LORAN_Section_1.asp | ||
http://www.scribd.com/doc/35814242/MIT-Radiation-Lab-Series-V2-Radar-Aids-to-Navigation | http://www.scribd.com/doc/35814242/MIT-Radiation-Lab-Series-V2-Radar-Aids-to-Navigation | ||
OTHERS - not consulted | OTHERS - not consulted | ||
I. B.W. Sittelry, “ELEMENTS OFLORAN,” MIT Radiation Laboratoyr Re- port No. 499; March, 1944; also available as Navships 900, 027, Bureau of Ships, April 1944 | I. B.W. Sittelry, “ELEMENTS OFLORAN,” MIT Radiation Laboratoyr Re- port No. 499; March, 1944; also available as Navships 900, 027, Bureau of Ships, April 1944 | ||
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5. J.A. Pierce, “THE FUTURE OF HYPERBOLIC NAVIGATION.” MIT Radiation Laboratory Report No. 625; August 1945 | 5. J.A. Pierce, “THE FUTURE OF HYPERBOLIC NAVIGATION.” MIT Radiation Laboratory Report No. 625; August 1945 | ||
6 . “THE LORAN SYSTEM,” Electronics, vol. 18, 00. 94-100, November, 1945;vol. 18, pp. 1IO- 116,December, 1945;and vol. 19,pp. 109-I 15,March, I946 | 6 . “THE LORAN SYSTEM,” Electronics, vol. 18, 00. 94-100, November, 1945;vol. 18, pp. 1IO- 116,December, 1945;and vol. 19,pp. 109-I 15,March, I946 | ||
7. Alexander A. McKenzie, “LORAN-THE LATEST IN NAVIGATIONAL AIDS,” QST, Part I , vol. 29. pp. 12-16. December, 1945; part 2. vol. 30, pp. 54-57. January, 1946; part 3, vol. 30, pp, 62-65, February, 1946 | 7. Alexander A. McKenzie, “LORAN-THE LATEST IN NAVIGATIONAL AIDS,” QST, Part I , vol. 29. pp. 12-16. December, 1945; part 2. vol. 30, pp. 54-57. January, 1946; part 3, vol. 30, pp, 62-65, February, 1946 | ||
http://www.insidegnss.com/node/1806#Baseband_Technologies_Inc_ | http://www.insidegnss.com/node/1806#Baseband_Technologies_Inc_|a5=Early example of a critical war .. CRASH engineering project. | ||
|a5=Early example of a critical war .. CRASH engineering project. | |||
Global, air and ships | Global, air and ships | ||
Time was critically important, getting the radio navigation grid up and running | Time was critically important, getting the radio navigation grid up and running | ||
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By July of 1943 also two other projects long recommended by Captain Harding began to take definite shape and proportions. The report of Lt. Cowie Acting NLOL for June 31 states; | By July of 1943 also two other projects long recommended by Captain Harding began to take definite shape and proportions. The report of Lt. Cowie Acting NLOL for June 31 states; | ||
"Development of technique and equipment for providing day-time service equal in radius to night-time service by use of a single high frequency...status: investigation of E-layer day-time transmission of high frequency has been completed and the use of a frequency of approximately 10.5 mcs. authorized. It is the opinion of Radiation Laboratory that this frequency will give a satisfactory day-time range of service from 800 to 1,300 miles although it is expected that the 10.5 mcs. signals will be some what weaker that 2 mc. signals. A program to obtain and modify transmitters and start a service test on this frequency will be started in the near future." | "Development of technique and equipment for providing day-time service equal in radius to night-time service by use of a single high frequency...status: investigation of E-layer day-time transmission of high frequency has been completed and the use of a frequency of approximately 10.5 mcs. authorized. It is the opinion of Radiation Laboratory that this frequency will give a satisfactory day-time range of service from 800 to 1,300 miles although it is expected that the 10.5 mcs. signals will be some what weaker that 2 mc. signals. A program to obtain and modify transmitters and start a service test on this frequency will be started in the near future." | ||
The experiments that had been in progress for some time in the Laboratory to develop an automatic synchronizer seemed also to begin bearing fruit as about this time one was developed which did not deviate nor lose control through high noise levels including electrical storms. Four of these units were being built by the laboratory and by July so confident were they of the worth of the auto-sync that the Laboratory placed an order for sixty of these units based on their prototype to be delivered around the end of 1943. | |||
|a7=The original research and design work was carried out in the Hood Building in Cambridge, close to but outside the MIT campus. The proposed milestone plaque could be mounted on MIT Building N42, on Massachusetts Avenue, close to where the original Hood Building used to be. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out | The experiments that had been in progress for some time in the Laboratory to develop an automatic synchronizer seemed also to begin bearing fruit as about this time one was developed which did not deviate nor lose control through high noise levels including electrical storms. Four of these units were being built by the laboratory and by July so confident were they of the worth of the auto-sync that the Laboratory placed an order for sixty of these units based on their prototype to be delivered around the end of 1943.|a7=The original research and design work was carried out in the Hood Building in Cambridge, close to but outside the MIT campus. The proposed milestone plaque could be mounted on MIT Building N42, on Massachusetts Avenue, close to where the original Hood Building used to be. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out | ||
Boston Section Milestone History Committee is currently seeking approval from MIT to carry this out. | Boston Section Milestone History Committee is currently seeking approval from MIT to carry this out. | ||
LORAN operators were trained somewhere in Boston. Transmitters and receivers were fabricated by large manufacturers located elsewhere.|a8=No|a9=The proposed plaque would be be wall-mounted outdoors, probably attached to MIT Building N42, alongside other plaques at 211 Massachusetts Avenue. The plaque would be readily visible to pedestrians walking on this public sidewalk. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out|a10=MIT|a11=No|a12=The Boston Section with support from local Society Chapters, and financial contributions from sponsors.|a13name=Bruce Hecht|a13section=Boston|a13position=2010 Chair|a13email=Bruce Hecht|a14name=Robert Alongi|a14ou=Boston Section|a14position=Section Business Manager|a14email=sec.boston@ieee.org|a15Aname=Gilmore Cooke|a15Aemail=gilcooke@ieee.org|a15Aname2=|a15Aemail2=|a15Bname=c/o Robert Alongi|a15Bemail=sec.boston@ieee.org|a15Bname2=To be assigned later|a15Bemail2=|a15Cname=Gilmore Cooke|a15Ctitle=retired PE|a15Corg=Boston Section Executive Committee|a15Caddress=8 Canvasback, W. Yarmouth, MA 02673|a15Cphone=617-759-4271|a15Cemail=gilcooke@ieee.org}} | LORAN operators were trained somewhere in Boston. Transmitters and receivers were fabricated by large manufacturers located elsewhere.|a8=No|a9=The proposed plaque would be be wall-mounted outdoors, probably attached to MIT Building N42, alongside other plaques at 211 Massachusetts Avenue. The plaque would be readily visible to pedestrians walking on this public sidewalk. The Boston Section Milestone Committee is currently seeking approval from MIT to carry this out|a10=MIT|a11=No|a12=The Boston Section with support from local Society Chapters, and financial contributions from sponsors.|a13name=Bruce Hecht|a13section=Boston|a13position=2010 Chair|a13email=Bruce Hecht|a14name=Robert Alongi|a14ou=Boston Section|a14position=Section Business Manager|a14email=sec.boston@ieee.org|a15Aname=Gilmore Cooke|a15Aemail=gilcooke@ieee.org|a15Aname2=|a15Aemail2=|a15Bname=c/o Robert Alongi|a15Bemail=sec.boston@ieee.org|a15Bname2=To be assigned later|a15Bemail2=|a15Cname=Gilmore Cooke|a15Ctitle=retired PE|a15Corg=Boston Section Executive Committee|a15Caddress=8 Canvasback, W. Yarmouth, MA 02673|a15Cphone=617-759-4271|a15Cemail=gilcooke@ieee.org}} | ||
Revision as of 01:07, 8 December 2010
This Proposal has not been submitted and may only be edited by the original author.
