GNSS Trilogy: Our Story Thus
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GNSS Trilogy: Our Story GLEN GIBBONS EDITOR, INSIDE GNSS Thus Far “Tell me, O muse, of Oops! Wait a minute! Hold your the labyrinths of Brussels and that ingenious hero who horses there, Homer; it’s not Washington, and that most that Odyssey. We’re talking frightful ogre: the Office of traveled far and wide after about the GNSS odyssey. Management and Budget. he had sacked the famous More than 30 years in the No, it’s not The Lord of town of Troy. .” making, not a mere decade. the Rings or even the first And its heroes didn’t simply three installments of Harry drift idly about the wine- Potter’s adventures, but the dark Mediterranean enjoying GNSS trilogy has produced the rosy-fingered dawn like a fascinating story line and Odysseus and his buddies. The introduced a kind of magic to GNSS crew — GPS, GLONASS, the real world. It has created a and now Galileo — has traveled vast popular utility as profound from California to Colorado in its own right as the Internet to Brussels, Moscow, India, or mobile phones — with the Kazakhstan, Beijing, Tokyo, and ability to discover connections beyond! among people, places, and Oh, sure, Circe and things that were heretofore Polyphemus and the ghost of impossible and nearly Agamemnon made for some unimaginable. rough customers, but try launch But getting there hasn’t failures, dissolution of a nation, been easy. Read on… Russian Federal Space Agency/LockheedMartin/ESA www.insidegnss.com JANUARY/FEBRUARY 2006 • PREMIERE ISSUE InsideGNSS 25 igm_025-031_11.indd 25 2/8/06 8:48:47 AM GNSS TRILOGY falling below its fully operational Will Success Spoil GPS? capability (FOC) of 24 space vehicles sometime between 2007 and 2012 as The more that the Global Positioning System has exceeded the 20–40 percent. Indeed, the task force expectations of its creators, the more challenges it has faced. argues for a 30-satellite constellation to ensure robust coverage in “challenged ike some behemoth rocket environments.” ship launched in the 1970s, The timelines for the last three the Global Positioning System GPS satellite development and launch L sails on through an expanding programs — Block IIR, IIR-M, and III universe of users and applications, — all slid to the right, as they describe seemingly imperturbable, successful schedule delays these days. beyond the expectations of its creators, Intermittently starved for fuel, with an enormous momentum carrying it sporadic guidance from the helm, will into the third millennium. new resources reach the system before To all appearances, GPS is its speed inevitably begins to slow, prospering more than ever: a second threatening its being overtaken by other full signal (L2C) is becoming available GNSS vehicles? to civil and commercial users, a Okay, that’s the bad news. denser ground monitoring system The good news is that no one being built out, improved accuracies connected to the program wants to let squeezed out of the algorithms and one of the world’s leading U.S.-branded operational practices at the Master utilities slip into the shadow of the Control Station in Schriever Air Force other GNSSes under development. Base, prices dropping on products And steps are under way to ensure that with more features and functions than doesn’t happen. ever, hundreds of millions of receivers in use around the world. A follow-on New Game Plan generation (Block IIF) of satellites with A long-awaited next-generation a third civil signal (at the so-called L5 program, GPS III, spent well more than frequency) is being built by Boeing for hundred million dollars on conceptual launch beginning in 2007. studies and several years jogging in Since its first satellite launch 28 place before receiving a renewed go- years ago, GPS has blazed a trail for ahead from the Department of Defense satellite-based positioning, navigation, NASA (DoD). The Fiscal Year 2006 (FY06) and timing. Thanks to GPS, global navigation satellite systems federal budget allocated $87 million for GPS III. The FY07 have gone from being a technological unknown to becoming budget will be finalized soon in Washington, and current a widely recognized utility. GPS, a model and inspiration to indications are that GPS Block III will receive at least $237 its imitators across the oceans. million, according to the GPS Joint Program Office (JPO). Of Or is it? course, GPS III funds have been zeroed out before. In fact, for some years now GPS has been a victim of its Current plans call for GPS JPO decision this summer that own success. Performing better than advertised, the system chooses among proposals submitted for separate space vehicle has suffered from budgetary pilfering for other defense (SV) and operational control (OCX) segment contracts. Once programs and risks getting lost in the shifting maze of diffuse acquisition strategies are formally approved in Washington, dual-use management responsibilities. release of the GPS Block III SV request for proposals (RFP) “History has shown that the Air Force has had chronic are expected to be released by mid-February and later in the difficulty in adequately funding GPS, even in the absence spring for the OCX RFP, according to JPO. of the more expensive GPS III satellites,” observes a high- “Minor adjustments are being implemented in the program level Defense Science Board (DSB) task force report on GPS planning to reflect an incremental development and delivery issued late last year. “If the Air Force continues to use its approach for both acquisitions that will provide increased GPS investments as a funding source to offset other space/ GPS capability sooner and more frequently over the life of the aircraft programs, then GPS service continuity will remain in program,” the JPO told Inside GNSS. Nonetheless, an upgrade jeopardy even without the more costly GPS III.” (See article in the control segment to accommodate the new generations on page 42.) of satellites is behind schedule, which means that the capability Meanwhile, an Air Force Space Command projection to operationally control those signals will not be available until puts the worst-case probability of the GPS constellation 2009 at the earliest, according to the DSB task force. 26 InsideGNSS JANUARY-FEBRUARY 2006 • PREMIERE ISSUE www.insidegnss.com igm_025-031_11.indd 26 2/8/06 8:48:53 AM Modernizing Technology National Geospatial-Intelligence Agency (formerly the In terms of its fundamental design, the Global Positioning National Imagery and Mapping Agency) have been folded System is nearly 35 years old. More recent spacecraft designs into the existing five Air Force GPS monitoring stations using modern electronics, new rubidium clocks, better (which includes the Master Control Station at Shriever AFB, satellite management techniques, and navigation message Colorado.) This will eliminate blank spots in coverage and enhancements have improved performance. But the design of support Air Force plans to monitor the integrity (or health) of the key resource for manufacturers and users, the GPS signals- civil signals as well as military signals. in-space, is essentially the same as when the first satellite was launched in 1978: a C/A-code on L1 (centered at 1575.42 New Political Structure MHz) and P/Y-code military signals at L1 and L2 (1227.60 Under a presidential national security policy directive MHz) (NSPD) released in December 2004, a National Space-Based Over the next five years, however, this situation will change Positioning, Navigation, and Timing (PNT) Executive dramatically. Committee and Coordination Office have taken over from the Beginning with SVN53/PRN17, the first modernized Interagency GPS Executive Board (IGEB). Mike Shaw, a long- Block IIR (IIR-M) satellite built by Lockheed Martin and time GPS hand on both sides of the civil/military interface, launched last September 25, GPS has gained a new open civil stepped in toward the end of 2005 as the first director of the signal at L2 (centered at 1227.6 MHz). A third civil signal, PNT coordination office. L5 (centered at 1176.45 MHz) will arrive with the Block IIF satellites now scheduled to begin launching in 2007. The good news is that no one connected to the program wants to let one of the world’s leading U.S.-branded utilities slip into the shadow of the other GNSSes under development. Gordon EnglaNd Maria Cino Both IIR-M and IIF satellites will offer new military Establishment of the PNT committee — now cochaired M-code signals at L1 and L2 with “flex power” capability of by deputy secretaries of defense and transportation, Gordon transmitting stronger signals as needed. The L5 civil signal England and Maria Cino, respectively — kicked GPS will be broadcast both in phase and in quadrature, with the leadership up a notch from that of the IGEB. Other members quadrature signal being broadcast without a data message. include representatives at the equivalent level from the Air Force Space Command expects to have a full complement departments of state, commerce, and homeland security, the of satellites transmitting L2C and M-code signals by 2013; for Joint Chiefs of Staff and the National Aeronautics and Space L5, fully operational capability is expected by 2014. Administration. Generally, the new signals will be characterized by longer The committee had met once shortly after its formation code sequences broadcast at a higher data rate and with under President Bush’s NSPD, but a January 26 gathering slightly more power. Beginning with the IIR-M satellites, the marks its first with the current leadership. In addition to Air Force will be able to increase and decrease power levels getting acquainted with one another and the PNT topic in on P-code and M-code signals to defeat low-level enemy general, the agenda covered such issues as the DSB task force jamming — a capability known as “flex power.” report, modernization and funding of GPS, and the new UN These new signal features will support improved ranging International Committee on GNSS (see article on page 61).