跳到主要內容

protectionism and tariffs of various GNSS

Sometimes more overt forms of shaping domestic markets arise. Both Russia and China have announced plans to require commercial transportation operators in their countries to use their respective national GNSS systems.

Russia has also drawn criticism for its efforts to impose tariffs on imports of navigation devices that don’t incorporate GLONASS capability, and Europe once proposed fees on receivers that would have taxed GPS as well as Galileo.
Russia’s recent announcement to require civil aircraft operating in its domestic airspace to carry GLONASS equipment has caused a controversy still under way at ICAO and among aircraft manufacturers.
China has yet to reveal any regulatory plans that would affect foreign companies entering its domestic market with BeiDou-capable products, although the nation’s Certification and Accreditation Administration (CNCA) says it will establish “an authoritative testing and certification system” for BeiDou equipment by 2015. 

In short, everybody is trying to find the sweet spot between open trade and protectionism, between supporting domestic manufacturers and accessing foreign markets, meanwhile running the gauntlet of regulatory filters and competitive advantages that fill the world of commerce. Amid all this positioning of individual systems, GNSS operators still must meet the increasingly clear expectation of users for transparent, synergistic, seamless, ubiquitous solutions.
Interoperability
The lead organization promoting multilateral efforts among system operators, the International Committee on GNSS (ICG), grew out of an initiative by the United Nations Committee on the Peaceful Uses of Outer Space.
The ICG’s primary objectives are to encourage compatibility — that is, avoiding harmful interference among systems — and interoperability, using GNSS services together to provide better capabilities than can be achieved by individual systems alone. In fact, the first of four ICG subgroups — Working Group A — specifically addresses compatibility and interoperability issues.
Ultimately, overseeing RF compatibility falls under the responsibility of the Radiocommunication Bureau of the International Telecommunications Union (ITU), another UN-affiliated organization. So, the ICG’s real contribution has come in the area of interoperability.
Formally established in 2005, the ICG provides an invaluable forum for multilateral discourse — a venue where GNSS system operators can work out terms of reference, introduce new cooperative ventures, and try to agree on common goals toward which to work.
A number of other efforts are under way that could eventually cohere into — or at least contribute to — a more comprehensive infrastructure to support interoperability.
The 17-member Multi-GNSS Asia (MGA) is organizing a demonstration campaign to take advantage of the rich GNSS signal resources in the Asia-Pacific region.
And, last November, China’s BeiDou office issued a call for participation in an international GNSS Monitoring and Assessment System (iGMAS), first proposed at the ICG-6 meeting in Japan in 2011.
The iGMAS would do the following: equip multi-GNSS reference stations with BeiDou/GPS/GLONASS/Galileo-capable receivers, set up new tracking stations jointly for GNSS monitoring and assessment, perform joint experiments addressing technical issues of GNSS monitoring and assessment, define and formulate jointly the GNSS monitoring parameters covering GNSS constellation status, navigation signals, navigation messages, and service performance, and develop and share products jointly.
No musical group is conducted by consensus, however. Indeed, like barbershop quartets, the GNSS programs may have to harmonize by taking their cues from one another. So, bilateral negotiations and agreements will continue in parallel with the multilateral efforts.
Receiver versus System Solutions. Many of the differences among GNSS signals can be reconciled within the receivers to produce a melded position/velocity/time (PVT) solution. But the greater and more numerous the corrections needed, the greater the computational overhead on the device itself, as well as adverse effects on performance, size, weight, power, and cost.
Ideally, the various GNSS systems would converge on common standards. Optimizing the alignment of signals and frequencies, time and geodetic coordinate systems, however, are long-term projects — although the sooner progress is made on them, the sooner they become a present reality.
Another approach would actually create an common, active monitoring system with direct participation of all the GNSS providers — also a challenging prospect.
A shorter path could involve putting data into spare frames of the various GNSS services’ navigation messages to correct offsets between their geodetic and time frames and those of other systems. A couple of years ago, GPS godfather Brad Parkinson proposed what he called a Cross-Augmentation Reference System (CARS) in which each GNSS SV would broadcast corrections — similar to those transmitted by the Wide Area Augmentation System (WAAS) — to allow that satellite to be seamlessly operated as a part of any other constellation.
The plan would avoid the issue of which time or which geodetic system to use and enable GNSS providers to retain some control over use of their own system, Parkinson said, characterizing such an approach as “interchangeability.”
But even this would require an arduous and lengthy process of bilateral and multilateral negotiations to coordinate changes in basic GNSS navigation messages.
Another approach, advocated by Lu Xiaochun of the Chinese Academy of Sciences National Time Service Center, would add such data to other space-based or terrestrial systems, such as the Internet, the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), or mobile communication services.
First, however, the individual programs have to look to their own needs and circumstances — to ensure that their systems are robust, their financing secure, and their technologies forward-looking and future-proofed.

留言

這個網誌中的熱門文章

CMOS sensor trends and astrophotography, from amateur astronomers perspective

Nowadays, even in low light conditions, digital camera can quality pictures with higher ISO, noise and hot pixels have been gradually reduced. Sony has introduced back illumination process for consumer market. Sony BSI sensors evolved  from Exmor to now Exmor RS( stacked) technology. This stacked technology allows further chip size reduction, which has strong demands in smartphone camera market. Digital astrophotography is also benefited from such advances, utilising Back Side Illumination technology Exmor: Within the CMOS sensor, it outputs low-noise digital signals by "on-chip column AD conversion" and "dual noise reduction" to suppress noise in the first half of the process In low light conditions, when a wide aperture is desirable to collect as much light as possible. At apertures wider than f/2.0, back-illuminated Exmor R sensors are significantly more efficient at collecting light than conventional, front-illuminated sensor...

ultrafast rendezvous to ISS

    14 Oct 2020,  being the first to use a new “ultrafast” rendezvous” scheme with the ISS. Following a flawless ascent to the correct orbit, Soyuz 2 .1a , Soyuz MS-17 caught up with the orbiting laboratory in only two orbits (three hours), halving the time it takes for crew to get to the Station.   The three space travelers of the Soyuz MS-17 mission launched on a six-month mission the International Space Station.  previous 3/4 orbit rendezvous: Soyuz MS-16 4 orbit rendezvous A three-orbit profile was deemed possible without major flight design changes after inauguration of the Soyuz 2-1A rocket that provides a much higher orbit injection accuracy than its predecessors and would allow the two correction maneuvers on Orbit #2 to be eliminated while the Automated Rendezvous Phase would still remain untouched. The deletion of the Orbit #2 maneuvers was expected to slightly tighten the already restrictive phase angle window from and upper limit of 30-35° to 25-28°...

Scythians 斯泰基 塞種 西古提人

900 BC - 200 AD British museum   Tomb of scythe prince, Buktarma valley, 1200 masl, Google map Herodotus   絲路上的帝國 Biblegeography   哥羅西書 3:11  在此並不分希利尼人、猶太人、受割禮的、未受割禮的、化外人、 西古提人 、為奴的、自主的.惟有基督是包括一切、又住在各人之內。 塞種 塞迦  saka 史記漢書 西域傳: 塞種  ctext 昔匈奴破大月氏,大月氏西君大夏,而塞王南君罽賓。塞種分散,往往為數國。自疏勒以西北,休循、捐毒之屬,皆故 塞種 也。 匈奴列傳 Ctext :塞王 《史記》在《大宛列傳》與《匈奴列傳》中, 詳細 記錄了中亞至天山一帶的塞種(塞王、塞地)狀況。例如,文中記載了月氏西破走塞王,導致塞人南遷越過懸度(今帕米爾高原及克什米爾一帶) Baike Genetic history   Genetics  Nih griffin  ? Scytho-Siberian  world 塞迦 saka  wiki Disappeared? Sarmatians ( 薩爾馬泰 , 奄蔡 史記 ,  Aorsi )and goths YouTube