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Incorrect. The relevant agreement is the Missile Technology Control Regime, an informal partnership between 34 countries. http://en.wikipedia.org/wiki/Missile_

by ceequof 11y ago

Incorrect. The relevant agreement is the Missile Technology Control Regime, an informal partnership between 34 countries. http://en.wikipedia.org/wiki/Missile_Technology_Control_Regime http://en.wikipedia.org/wiki/Missile_Technology_Control_Regi... Unlocked GPS receivers are classified as dual-use missile-related components under category II, item 11, section A.3: http://www.mtcr.info/english/MTCR-April2011-Technical-Annex.pdf http://www.mtcr.info/english/MTCR-April2011-Technical-Annex.... b. Designed or modified for airborne applications and having any of the following: 1. Capable of providing navigation information at speeds in excess of 600 m/s; 2. Employing decryption, designed or modified for military or governmental services, to gain access to GNSS secure signal/data; or 3. Being specially designed to employ anti-jam features (e.g. null steering antenna or electronically steerable antenna) to function in an environment of active or passive countermeasures.

tyho 11y ago
Huh, I should have checked that first. How well do you think you could argue that since the treaty did not specify what reference frame you were supposed to use to calculate the 600 m/s limit, you decided to use the reference frame of the receiver and therefore no limit is required because the speed is always 0? I would have thought GPS people most of all would have understood this problem \s.
- ceequof 11y ago
  My crystal ball tells me that the judge would find your argument very amusing, but not substantive.
jevinskie 11y ago
Unfortunately many receivers have a (speed > X || altitude > Y) check when, IIRC, the law only requires (I don't see the altitude part in your quote) (speed > X && altitude > Y). I think the altitude limit was 20 km or 25 km. Anyways, it is a pain for people who want to put a receiver on a high altitude balloon. I was able to... find... a modified firmware for my SIRF receiver but I have been to afraid to flash it. Besides, I don't even know if the receiver has the "bad" logic. I've been jonesing to make a SDR GPS simulator that generates a signal that I can feed directly into the antenna port on the receiver to test high altitude functionality.
- ceequof 11y ago
  MTCR is an informal agreement, not a treaty. Its provisions are actually implemented by laws in the member nations-- in the US, that's the International Traffic In Arms Regulations Act. (ITAR) ITAR Category XV, Section c: Global Positioning System (GPS) receiving equipment specifically designed, modified or configured for military use; or GPS receiving equipment with any of the following characteristics: 1. Designed for encryption or decryption (e.g., Y-Code) of GPS precise positioning service (PPS) signals; 2. Designed for producing navigation results above 60,000 feet altitude and at 1,000 knots velocity or greater; So the US limit isn't even in metric units! Consulting my psychic powers, since I haven't bothered to dig up the laws for each member nation, I predict that each nation implements MTCR slightly differently, some using the word AND, some using the word OR. Since a GPS manufacturer wants to sell worldwide, they would have to use the strictest limits possible.

by ceequof 11y ago

tyho 11y ago

Huh, I should have checked that first. How well do you think you could argue that since the treaty did not specify what reference frame you were supposed to use to calculate the 600 m/s limit, you decided to use the reference frame of the receiver and therefore no limit is required because the speed is always 0? I would have thought GPS people most of all would have understood this problem \s.

ceequof 11y ago
My crystal ball tells me that the judge would find your argument very amusing, but not substantive.

jevinskie 11y ago

Unfortunately many receivers have a (speed > X || altitude > Y) check when, IIRC, the law only requires (I don't see the altitude part in your quote) (speed > X && altitude > Y). I think the altitude limit was 20 km or 25 km. Anyways, it is a pain for people who want to put a receiver on a high altitude balloon. I was able to... find... a modified firmware for my SIRF receiver but I have been to afraid to flash it. Besides, I don't even know if the receiver has the "bad" logic. I've been jonesing to make a SDR GPS simulator that generates a signal that I can feed directly into the antenna port on the receiver to test high altitude functionality.

ceequof 11y ago
MTCR is an informal agreement, not a treaty. Its provisions are actually implemented by laws in the member nations-- in the US, that's the International Traffic In Arms Regulations Act. (ITAR) ITAR Category XV, Section c: Global Positioning System (GPS) receiving equipment specifically designed, modified or configured for military use; or GPS receiving equipment with any of the following characteristics: 1. Designed for encryption or decryption (e.g., Y-Code) of GPS precise positioning service (PPS) signals; 2. Designed for producing navigation results above 60,000 feet altitude and at 1,000 knots velocity or greater; So the US limit isn't even in metric units! Consulting my psychic powers, since I haven't bothered to dig up the laws for each member nation, I predict that each nation implements MTCR slightly differently, some using the word AND, some using the word OR. Since a GPS manufacturer wants to sell worldwide, they would have to use the strictest limits possible.