Compass — Chinese SatNav or Galileo Bluff?

As has been widely reported, China plans to con­struct its own global satel­lite nav­i­ga­tion net­work. Or so it would appear. No ones quite sure. The sys­tem, dubbed Compass, is mired in con­fu­sion, with pos­si­ble inten­tions rang­ing from a mod­est upgrade of their regional Beidou sys­tem to a full blown com­peti­tor to GPS and Galileo.
China invested in the European Galileo sys­tem through the Galileo Joint Undertaking. Remarkably, this invest­ment will not allow the Chinese any role in Galileo when it tran­si­tions to the Supervisory Authority at the end of the year, likely due to the sen­si­tive nature of Galileos encrypted sig­nals. Its no sur­prise, then, that China would feel betrayed by its part­ner­ship in the Joint Undertaking. Compass may be a result of Chinas desire to strike out on its own or a bluff aimed at wran­gling a more sub­stan­tive role in Galileo.
The busi­ness case for Galileos com­mer­cial sig­nals is ques­tion­able, since most peo­ple are con­tent with using GPS and the free Galileo sig­nals. Another com­mer­cial com­peti­tor, such as Compass, would surely hurt Galileo. As such, China can eas­ily use Compass as lever­age for bet­ter stand­ing within the Supervisory Authority.
China has ordered 18–20 rubid­ium atomic clocks, a key com­po­nent of satel­lite nav­i­ga­tion sys­tems. However, this is nowhere near enough to cre­ate a global con­stel­la­tion, which requires at least 21 satel­lites, espe­cially since there are usu­ally mul­ti­ple clocks per satel­lite, with GPS satel­lites hav­ing at least three and Galileo hav­ing four.
At best, China would be able to build eight or nine satel­lites with just two clocks each, which would allow for a regional nav­i­ga­tion sys­tem for East Asia and the Indian sub­con­ti­nent. Such a sys­tem would not be a com­mer­cial threat to Galileo, but has poten­tial to become a global com­peti­tor fairly quickly if China buys more clocks; this ini­tial order may only rep­re­sent a first install­ment.
The International Telecommunications Union (ITU) data­base has 36 satel­lite slots reg­is­tered to Compass. Fourteen are in geo­syn­chro­nous orbits, and the remain­ing 22 are in the medium orbits tra­di­tion­ally used for nav­i­ga­tion sys­tems. While there is a ten­dency to reg­is­ter more slots with the ITU than will real­is­ti­cally be filled, such a large num­ber of reg­is­tra­tions for a regional sys­tem would be exces­sive and place China in a poor posi­tion with the ITU for future reg­is­tra­tions.
What is Europe to do? The eco­nomic returns on Galileo must be pro­tected if the project is to suc­ceed. China could be given rights under the Supervisory Authority, min­i­miz­ing its need for Compass. However, this would prob­a­bly allow Chinese com­pa­nies to build Galileo ground receivers, a poten­tially lucra­tive mar­ket that Europe would like to keep for itself. It would also give China access to the encrypted, and sen­si­tive, public-​​safety sig­nals. The stakes are high, but can Europe afford to call Chinas bluff?
An inter­est­ing aside: there is no guar­an­tee that the clocks would be used for Compass. Another pos­si­ble appli­ca­tion is naval sig­nal recon­nais­sance satel­lites sim­i­lar to the Navys Ocean Surveillance Satellites pro­gram. In that case, the clocks are used for radio infer­om­e­tery, in turn deter­min­ing the ori­gin of the inter­cepted sig­nals. Such a capa­bil­ity for the Chinese would undoubt­edly have sig­nif­i­cant mil­i­tary impli­ca­tions. That pos­si­bil­ity, how­ever, is a sub­ject for another day.
Another con­sid­er­a­tion: there is a pos­si­bil­ity that Compass could jam GPS and Galileo. Even as a regional sys­tem, Compass could have sig­nif­i­cant mil­i­tary impli­ca­tions. These aspects will be dis­cussed in another entry tomor­row.
– Ryan Caron

August 3rd, 2006 | Eye on China, Space | 207481 Comments »http://defensetech.org/2006/08/03/compass-chinese-satnav-or-galileo-bluff/Compass+-+Chinese+SatNav+or+Galileo+Bluff%3F2006-08-03+20%3A04%3A49sharon_weinberger You can skip to the end and leave a response. Pinging is currently not allowed.