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1.

 

PID (Point ID) A unique short identifier for each marker (usually a 4 digit integer.) Only 
letters, numbers and the underscore are allowed in the PID. This number ends up as the 
first four characters of the filename submitted to OPUS and can be used to correlate 
occupations to OPUS solutions. 

2.

 

Description  A longer description of the point. Note that quotes “ and ‘ are not allowed in 
the description. 

3.

 

HI  The Instrument Height which is the distance from the ground mark to the bottom of 
the receiver 
 

add ‘F’ to enter feet 

 

add ‘S’ to enter slant height 

 

add ‘SF’ or ‘FS’ to enter slant feet height 

4.

 

Operator  This value gets placed in exported RINEX files 

5.

 

Agency  This value gets placed in exported RINEX files 

If the ‘_New’ folder gets too full, you can make a new project folder (with the “+” button) and move 
some occupations to the new project: 

 

Submitting an Occupation to OPUS 

 

NOTE: The iGx Dowload tool will run under Windows XP however it is not possible to 
submit observation files to NGS OPUS from a Windows XP machine. This limitation is 
imposed by the NGS, not by iGage and there is no work-around. 

Once all of the new occupations have downloaded you can submit an occupation to NGS OPUS, NGS 
OPUS-RS, RTX, AUSPOS. IBGE or post-process them using other software / services. 

Click on an occupation to select it: 

 

 

Click on the 'Submit to OPUS' button: 

 

 

The currently selected occupation will be processed and prepared for upload to OPUS: 

1.

 

the file is decimated to 15-second epochs, header information is stuffed 

2.

 

the file is run through TEQC to insure it will be acceptable to OPUS 

3.

 

an Observation file and a Navigation file are generated 

4.

 

the Observation file is compressed into a ZIP file 

If the ‘Show Advanced Settings’ is set to “Simple” then the program will skip directly to the ‘Verify 
Filename to Upload’ screen (shown below.) If ‘Show Advanced Settings’ is set to “Normal”, “Support 
OPUS-Projects” or “Advanced” then this ‘RINEX Solution’ helper screen is shown: 

Summary of Contents for iG4

Page 1: ...iG4 Static GNSS Receiver User Manual Revision S 2019 08 13 B9630 ...

Page 2: ... a registered trademark of Bluetooth SIG Inc FCC Notice iG4 receivers comply with the limits for a Class B digital device pursuant to the Part 15 of the FCC rules when it is used in the Portable Mode Operation is subject to the following two conditions 1 This device may not cause harmful interference and 2 this device must accept any interference received including interference that may cause unde...

Page 3: ...vation Mask 27 Update Firmware 28 OPUS What is it 30 OPUS RS Rapid Static 30 OPUS Projects 31 OPUS Error Messages and Failures 31 Interpreting OPUS Results 31 Getting ready to use OPUS 32 Using OPUS Projects 34 Best OPUS Practices for New and Experienced Users 35 The OPUS Error Message Joke 35 1 OPUS RS is Dicey 35 2 Only Some Submissions are being returned by OPUS 35 3 OPUS RS is Very dependent o...

Page 4: ...4 RMA 57 ...

Page 5: ...have questions or suggestions don t hesitate to contact us iGage Mapping Corporation 1545 South 1100 East Suite 1 Salt Lake City UT 84105 USA 1 801 412 0011 email support igage com Your input is extremely valuable to us and we will listen to your suggestions Software updates and news are available from www iGage com Click on the Support link and then find the iG4 resource link Technical Specificat...

Page 6: ...lue LED will flash once for every tracked Satellite 4 Verify that the yellow Files LED flashes once every 5 seconds or 1 second if configured as the receiver logs data 5 Let the receiver record data for at least OPUS Rapid Static 16 minutes OPUS Static 121 minutes 6 Turn the receiver off by pushing and holding the ON OFF button for 1 second Office Desktop 7 Install the download tool from the inclu...

Page 7: ...d to Static button as prompted at the bottom of the screen Exporting to other Programs NOT OPUS The files that are submitted to OPUS are decimated and stripped of all satellite information except for GPS Galileo GLONASS and BeiDou are removed If you are using the iG4 occupation file in another application select the Configuration tab then choose Show Advanced Settings Normal or Advanced An Export ...

Page 8: ... compatible static raw data sets Each receiver kit includes these items A Hard Shell Carry Case This User Manual iG4 GNSS Head The iG Download DVD GPS to PC Data Cable Serial USB and Ext Power A high capacity 7 4 V Lithium Ion Battery Quad Battery Charger Power Adapter with Cord A Hold A Pole External Battery Power Clips ...

Page 9: ... absence of specific alerts does not mean that there are no safety risks involved Warning and Caution information is intended to minimize the risk of personal injury and or damage to the equipment Use and Care The iG4 receiver is a field ready instrument however it is also a delicate electronic instrument Take suitable care to avoid damage to the instrument Avoid dropping the receiver as it can ch...

Page 10: ... or puncture the battery Do not open the battery or short circuit its contacts Do not charge the batteries in chargers other than the supplied charger or a direct replacement Do not charge similar batteries in the supplied charger even if they fit well Do not short circuit the battery terminals or store batteries in a way that allows inadvertent shorting WARNING Avoid contact with the rechargeable...

Page 11: ... power is attached Next to each battery is a GREEN LED GREEN LED STATUS Off No Battery Inserted Blinking Battery Charging ON Steady Battery is fully charged After a battery is fully charged it is recommended to remove the battery for extended storage Optional Accessories Optional Heavy Duty External Power Cables are available for the iG4 from iGage They are reasonably priced and are perfect for at...

Page 12: ...eiver Power Red Power is ON If flashing the battery charge is very low SV s Satellite Count Blue Blinks once for each tracked satellite waits 5 seconds repeats Serial Green Blinks when data is received by the serial port Blinks when the Record button is pressed if the receiver is storing to a static file Files Yellow Blinks each time data is stored to the static file When the receiver turns on All...

Page 13: ...uld provide external power to the receiver with the included battery clips the power supply or the optional heavy duty power cable If you use an external battery power you MUST also provide a charged battery in the receiver 1 Place a freshly charged battery into the receiver 2 Place the receiver above the point you want to survey 3 Rotate the receiver so the pushbutton panel faces the North 4 Leve...

Page 14: ... the box and is available by web download Installing the Download Tool Insert the provided disk in the DVD ROM drive of your computer and the installation tool should automatically run If you don t have a DVD ROM drive you can download the latest version of the tool from www iGgps com click on the iGx Download tool link to get the latest program version Follow the on screen instructions to install...

Page 15: ...n and has mounted as a lettered drive just press The program will automatically switch to the _New project and download every new file from your receiver As files are downloaded they are marked on the receiver as Downloaded however they are not deleted from the receiver and may be manually downloaded again at a later time if needed As the HCN binary files are downloaded from the receiver they are ...

Page 16: ...OTE The iGx Dowload tool will run under Windows XP however it is not possible to submit observation files to NGS OPUS from a Windows XP machine This limitation is imposed by the NGS not by iGage and there is no work around Once all of the new occupations have downloaded you can submit an occupation to NGS OPUS NGS OPUS RS RTX AUSPOS IBGE or post process them using other software services Click on ...

Page 17: ...ically entering the Zipped observation file name into the browse dialog Click OK and then Choose File to Upload will be displayed Press Control V then the Enter key on your keyboard You may also press Control V then click the Close button with your mouse You will need to manually select the correct antenna type Click anywhere in the antenna selection box In the drop down selection box Enter IG4 an...

Page 18: ...fy the device type while the receiver is connected on the Configuration tab Viewing the Observation Log Hidden when Simple A detailed log is automatically kept for the files that you download and submit for processing Pressing the Log button shows the log file for the currently selected observation Pressing the Append button adds a date time stamp and opens the log for user editing Press Save to s...

Page 19: ... will launch the UNAVCO TEQC tool and run a standard RINEX QC run on the currently selected observation file When the run is complete the results will be shown in a window You can press the TEQC Help button to download the User Guide for TEQC from the UNAVCO web site TEQC is a great tool for evaluating both the receiver s performance and the site suitability for collected data We use it to verify ...

Page 20: ...the default operator Email your email address If you change Show Advanced Settings from Simple to Normal Support OPUS Projects or Advanced additional setup values are shown You can change the rest of the configuration values as needed Here are detailed descriptions for each of them Base Project Folder Hidden when Simple This is the full Window s path to the base folder where all of the data is sto...

Page 21: ...e backups however they are standard ZIP files and the Windows operating system does include a tool to decompress them GPS Mounts on Drive This is the drive letter that the GPS receiver was last found on Don t worry if the drive letter changes the program will automatically find the receiver when you download data If you want to verify that the GPS receiver is connected and has successfully mounted...

Page 22: ...0 and you won t have to worry about HI blunders FEET If you measure up in feet you can enter the height in decimal feet and put an F after the measurement The program will automatically convert to Meters for you SLANT HEIGHT in Meters If you measure a slant height enter an S after the measurement and the program will compute the vertical height for you SLANT HEIGHT in FEET If you measure a slant h...

Page 23: ... exported directly to RINEX are not decimated Your Email When you submit a file to OPUS you need to provide your Email address so the OPUS processor can return a solution to you The email address that you enter here will be automatically entered for all submissions performed by the program Show Advanced Settings This setting determines the complexity of the iGx Download program Simple the Default ...

Page 24: ...ted report we recommend that you check the Export 8 3 Filenames option Format Extended Only shown when PPP Service OPUS The NGS returns three styles of reports Standard Single Page Report Extended Standard baseline details State Plane in s Ft Standard XML Single Page XML For new OPUS users the Format Extended includes one important addition State Plane coordinates are shown in both Meters and US S...

Page 25: ... files and manually convert them to standard RINEX files Results are always placed in a subfolder named RINEX under the file to be converted 3 Mark One File Unread When files are downloaded from the receiver they are not deleted from the receiver The filename on the receiver is modified to begin with an underscore _ This function allows you to specify a single file to mark as unread Once a file is...

Page 26: ...r does not have a built in serial port you will need to use a USB to Serial converter We highly recommend the PN USB2 VE487 TG Tera Grand Premium USB 2 0 to RS232 Serial DB9 Adapter Supports Windows 10 8 7 Vista XP 2000 98 Linux and Mac Built with FTDI Chipset Which is available from Amazon for less than 12 To configure the receiver turn on the GPS receiver select the Show Advanced Settings checkb...

Page 27: ...available 1 second 2 seconds 3 seconds 59 seconds 1 minute 2 minutes 3 minutes 190 minutes 2 Hz 5 Hz The default interval 5 seconds allows for files to safely contain over 7 days of continuous observations If you intend to use the observation files with OPUS you must use one of these recording intervals 1 2 3 5 10 15 or 30 seconds Auto Sessioning The default Auto Sessioning setting is NONE Some ap...

Page 28: ... Once the current receiver s firmware version is shown the Check Web for Newer will be enabled Click on The program will check the internet for a newer version of GPS control software If updated firmware is available the new firmware will be downloaded and the Update Firmware button will be enabled click on The program will request that you turn off the receiver The firmware will be downloaded and...

Page 29: ...k on the Update button Turn on the GPS receiver After 5 seconds the blue bar will slowly move across the uploader screen When it reaches the end Click on OK then wait 30 seconds turn off the GPS receiver finally turn it back on Your receiver has the latest firmware ...

Page 30: ...most important contributions to vertical accuracy computed by OPUS is the length of occupation Longer times are better If you are concerned about elevation please remember that a 2 hour OPUS static observation has an expected height accuracy of 2 5 cm A 6 hour occupation has an expected accuracy of 1 5 cm OPUS RS Rapid Static Standard OPUS Static sessions require 2 hour observations OPUS RS sessio...

Page 31: ...f possible error messages when processing OPUS solutions It is our experience that almost all errors fall into a single category There is not enough nearby CORS data to effectively process your occupation yet In general the resolution is nearly always the same Wait until more data becomes available and resubmit your job If you are processing OPUS RS jobs in an area with very few CORS stations and ...

Page 32: ...orthometric height is NAVD88 GPS derived and typically is the elevation you need The Peak to Peak error estimate for the orthometric height includes the error estimate for the GEOID in addition to the Peak to Peak error estimate value for the ellipsoid height IMPORTANT The state plane coordinates are listed at the bottom in the right hand column They are in Meters If you need Feet you can convert ...

Page 33: ...you are using OPUS Projects then More Better b Checkout online Mission Planning tools for U S satellite availability using reasonable masks 15 degrees during collection periods If there are any periods with fewer than 6 SV s or PDOPS higher than 3 plan on occupying points longer E How long will you observe a site Again F Are your sites GPS compatible Are there obstructions higher than 10 degrees G...

Page 34: ...ing the NGS project ID 1 Turn ON OPUS Projects support On the Configuration tab set Show Advanced Settings to Support OPUS Projects or Advanced 2 Add the NGS registered OPUS Projects Project Identifier supplied by your project administrator Click the button Enter the exact identifier as the new project name Select the new Project and check the OPUS Project checkbox under the Project selector 3 Now...

Page 35: ...Static jobs fail and most of the Static jobs that fail initially will successfully process when resubmitted the following day When using OPUS RS or Static longer occupations are always better OPUS Static is always more reliable than OPUS Rapid Static Please remember if you are submitting 15 to 30 minute OPUS RS occupations they WILL fail regularly Don t be surprised and don t blame your receiver 2...

Page 36: ...ough stations close to your occupation In many areas a single offline CORS station without data will make OPUS RS impossible 4 Daily vs Hourly CORS Availability If you click a CORS station pin on the NGS CORS map you will get a station summary which includes an Availability note There are two availably types Daily Hourly Daily means that a full day s CORS station data is collected and then sometim...

Page 37: ...ations Red Hourly Stations Green If your observation is in the western part of the state there are only daily stations available Let s look at an example with two observations collected on the Northwest side of Utah near Wendover Nevada The two observations were performed Monday afternoon the red bars One is a section corner the other is vertical bench mark which is only 400 feet northeast of the ...

Page 38: ...ion data that spans midnight UTC It causes additional problems a few days after collection when OPUS is forced to splice ultra rapid and rapid orbits It causes additional problems in a few weeks if precise orbits become available for only the 1st portion of an occupation and OPUS has to splice precise orbits for the first portion and rapid orbits for the second portion 6 Offline CORS Stations Ofte...

Page 39: ... quality low loss coaxial antenna cables with dielectric filled connectors enjoy top of the line GNSS receivers with the latest firmware Stuff happens and some of the CORS stations are unreliable and a few are horrible No matter how bad a station might be NGS CORS will collect the bad data and the OPUS engine will use the bad data and then blame your occupation for all issues The only effective co...

Page 40: ... green error bands Coupled with continuous recent Data Availability this station appears be a great CORS resource However if you look at a station s Time Series and it looks similar to this You will want to ALWAYS exclude the station from your solutions If you catch this site on a bad day and it has a lot of them you can expect significant elevation and horizontal errors Even worse sites abound in...

Page 41: ...r to start tracking a few degrees below 10 or just allow it to track all the way to the horizon 0 degrees Elevation Mask Attributes of a great GPS location for collection OPUS ready occupations No overhead power lines No trees leaves on or leaves off No power poles wood or metal No radar or radio paths that cross over the top of the receiver No chain link fences nearby Locations under busy landing...

Page 42: ...bridged with times of good coverage However in general you should avoid the following scenarios Semi Trucks and Trains This bench mark is 3 feet north of the eastbound edge of pavement of I80 near Green River Wyoming It has fantastic views in all directions unfortunately a semi truck drives by every 20 seconds and completely obscures a receiver s view of the southern sky This forces the receiver a...

Page 43: ...ear view of the sky Even though this location has open water to the South it is directly underneath large trees Water can also be a source of significant multipath see the next section This is a BAD location Large Reflective Surfaces Nearby Your receiver trusts that the signals that it receives have traveled directly from the satellite to your antenna Large nearby surfaces present opportunities fo...

Page 44: ...anyons especially East West trending canyons will present full 100 obstruction below the ridge line to the South Most of the GPS satellites are to the South This is BAD RBUT below is a NGS CORS site and is the closest CORS site to the iGage office in Salt Lake City Utah This site is hindered by a solid mountain 30 mask to the South This could be a challenging location for GPS observations and is n...

Page 45: ...rtant sky is to the East South and West because there are never any GPS satellites directly north So if you are setting up in a field that is surrounded by large trees locations in the middle of the North side of the open area are preferable because the southern sky effectively opens up Longer Observations OPUS RS is especially vulnerable to bad sites If you think a site may have problems try to c...

Page 46: ...y any one hour OPUS RS occupation from 5 30 pm to 9 30 pm will certainly fail However a one hour OPUS RS occupation from 11 30 am to 12 30 pm or most of the rest of the day will probably be successful DOP is a function of how many and where the satellites are in the sky We prefer more satellites spread over a larger portion of the sky with one or more satellites in every quadrant 11 30 am Great 8 ...

Page 47: ...ror is also very common source of blundered instrument height The iGx_Download tool makes this computation automatically for you however you must keep track of Slant vs Vertical and Feet vs Meters Transposition of digits in random heights that occur with tribrachs on tripods is a common source of error Measurement to the wrong place on the antenna is a common source of error Mixing slant measureme...

Page 48: ...combinations ASH701945B_M NONE ASH701945B_M SCIT ASH701945B_M SCIS ASH701945B_M SNOW ASH701945C_M OLGA ASH701945C_M SCIS ASH701945C_M SNOW ASH701945C_M SCIT ASH701945C_M PFAN ASH701945C_M NONE Each revision has a different calibration you must select the correct model or you will introduce substantial height uncertainty to your solution Batteries In or Batteries Out Every single thing inside an in...

Page 49: ...wn as the Fresnel Zone Fresnel is pronounced with a silent s Frenel named after French physicist Monsieur Fresnel Wikipedia has an excellent article on the Fresnel effect https en wikipedia org wiki Fresnel_zone be sure to checkout the section on Fresnel Zone Clearance mid article The Fresnel effect explains for why your GPS receiver will track a satellite which is fully behind a building or ridge...

Page 50: ... there is signal energy everywhere Conclusion There are lots of things that can go wrong with OPUS occupations Some you can control some you can t If you stack multiple problems Bad Constellation Short Occupation Moderate Canopy Bad HI FAILURE Your OPUS solutions will fail or have high RMS estimates and the time you spent collecting the observation will be wasted The OPUS family of online tools OP...

Page 51: ... for 20 seconds B Unplug wait 15 seconds try again C Try another USB port D Use an external USB Hub this fixes intermittent disk mounts but we don t know why E Try other computers F Try turning off your PC wait a minute and then turn on again Reinsert the USB cable G Get the DevView tool from http www nirsoft net utils usb_devices_view html and use it to uninstall the errant device driver for the ...

Page 52: ...d the write operation is very very quick In addition the receiver monitors the battery voltage and automatically closes output files and shuts down a few seconds before the battery expires However if the battery has been allowed to deplete and then is used when downloading to the computer the battery will likely run down while the files are transferring Downloading files keeps files open most of t...

Page 53: ...N Signal Name Description 1 TXD Transmit Data PC receive data through this pin 2 RXD Receive Data PC transmit data through this pin 3 PWR External Power Input 9 15 V DC 4 PWR External Power Input 9 15 V DC 5 GND External Power Ground 6 GND External Power Ground 7 USB PWR USB Power 8 D USB Data 9 D USB Data 10 Not Used nc ...

Page 54: ...cable includes connections for GPS USB Serial and External Power Interface Cable External Power Battery Clips External power should be in the range 9 VDC to 18 VDC The supplied battery clip cable includes a fuse and is reverse polarity protected ...

Page 55: ... 0 1 0 1 6 1 9 1 9 1 7 1 4 1 1 0 9 0 9 0 9 1 1 1 2 1 4 1 6 1 8 2 1 0 0 0 0 1 5 5 7 103 3 0 0 0 3 0 6 0 9 1 1 1 2 1 3 1 4 1 3 1 2 1 2 0 9 0 7 0 7 1 2 2 2 3 7 0 0 0 Calibration Values L1 0 0808 Meters 0 0808 meters L2 0 1033 Meters 0 1033 meters Radius not to bumps 0 1800 meters SHMP 0 0400 meters If you encounter an application that does not have the correct antenna model available the antenna mode...

Page 56: ...t height in feet you can enter a FS or SF after the measured slant height 4 512 FS becomes 1 323 meters vertical If you have a slant height in meters enter an S after the measured slant height 1 523 S becomes 1 480 meters vertical Manually Converting Heights 𝑣 𝑉𝑒𝑟𝑡𝑖𝑐𝑎𝑙 𝐻𝑒𝑖𝑔ℎ𝑡 𝑠 𝑆𝑙𝑎𝑛𝑡 𝐻𝑒𝑖𝑔ℎ𝑡 𝑟 𝑅𝑒𝑐𝑒𝑖𝑣𝑒𝑟 𝑅𝑎𝑑𝑖𝑢𝑠 ℎ 𝑆𝐻𝑀𝑃 𝑆𝑙𝑎𝑛𝑡 𝐻𝑒𝑖𝑔ℎ𝑡 𝑀𝑒𝑎𝑠𝑢𝑟𝑒𝑚𝑒𝑛𝑡 𝑃𝑜𝑖𝑛𝑡 𝑣 s2 r2 h Receiver Radius r meters SHMP h meters iG4...

Page 57: ...including trade secrets 8 Any damage due to accident resulting from inaccurate satellite transmissions Inaccurate transmissions can occur due to changes in the position health or geometry of a satellite or modifications to the receiver that may be required due to any change in the GPS IMC GPS receivers use GPS GLONASS BDS and GALILEO satellites to obtain position velocity and time information GPS ...

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