The Sokkia GSR1700 CSX Video on YouTube

We are all hearing about GNSS modernization and all the wonderful capabilities of new receivers, but have you ever stopped to wonder what it does for you?  How does all the marketing noise translate into you getting your job done faster and with more confidence?  Forget the hype – here is what you need to know.

L2C

Originally launched in late 2005, L2C is currently available on 6 satellites.  For you, L2C is like a stronger L2 signal, so you can track it easier in some places where L2 may be weak such as under light foliage.  But remember, multipath increases significantly under foliage; the benefits may be marginal.  In good GPS environments virtually no improvement in time to fix or position accuracy is seen due to L2C.  Look for it to offer some improved fix times in marginal environments once there are 19 or more satellites transmitting L2C.  This could be as soon as 2012, but with the current US economic situation, late 2013 is more realistic.  The good news:  minimal effort is needed for your current modern dual frequency gear to track L2C.  Ensure you keep the firmware up to date (check with Benchmark annually for any updates) to benefit from this signal.

L5

Fingers crossed this signal will be transmitting within the first half of 2009 experimentally.  The first fully functioning L5-capable satellite will launch in late 2009 or early 2010.  We will likely reach a level of 19 L5 satellites sometime in 2015 or later.  At that time L5 will deliver the possibility of triple-frequency RTK for faster, more reliable solutions.  The bad news is that these features will likely come at an additional cost to you, and may only be supported on certain receivers, but you have some time to save before then.

Galileo

The European Union has been pursuing their own satellite system that will operate independently from GPS, but, at the exact same L1 and L5 frequencies.  In theory this will make it easier to manufacture receivers that can receive both GPS and Galileo signals.  However, perpetual funding delays are pushing out the useful date for this system until 2013 officially.  That date was determined in 2007, when the European economy was performing well, so the date may slide further into the future too.  The good news:  a combined GPS L1/L5 and Galileo receiver will offer very fast, accurate and reliable RTK solutions.  These future receivers will offer significant improvements over what is currently on the market today.  The bad news:  you are left relying on EU and USA funding to launch many satellites at a significant cost.  Realistically this type of system will be available in 2015 and beyond.

GLONASS

Not everything is set in the future.  GLONASS has been available for many years, but due to poor Russian funding the system dwindled to 8 satellites in 2002.  Since 2007 they have worked steadily to improve the system.  There are currently 16 operational satellites.  For a combined GPS / GLONASS RTK system, such as the GSR2700 ISX, this translates typically to 2 to 3 additional ranges improving fix times and reliability.  With 9 satellites scheduled for launch in 2009, Russia’s renewed commitment to revitalizing GLONASS is on track to reaching 24 operational satellites in 2010.  This is one improvement that is actually delivering on its promise in a way that you can see and measure.  By 2010 GPS / GLONASS RTK receivers will track 40 to 50% more satellites than GPS-only systems.  This significantly improves your ability to get and maintain lock in partially obstructed environments such as around buildings and tree lines.

So while there are some interesting and exciting improvements on the horizon, only GLONASS offers usable performance today.  As the Russians continue launching, your GSR2700 ISX performance – and the performance of your crew - will continue to increase.  This is positive economic news we all want to be part of.  Contact Benchmark today to discuss how you can fast-track your team to improved efficiency.

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The information has largely been gathered from the internet from such sources as GPS World, Wikipedia, FAA, USAF, USCGNavCen, ESA, UNB, Boeing, Inside GNSS, NovAtel, Point Inc., the US Naval Observatory and other satellite information websites.