SiteMetrix Configuring RTK Corrections GPS receivers use a GPS Reference Station to obtain sub-centimeter position accuracy. The GPS Reference Station (Base Station) transmits RTK corrections to nearby GPS rovers over UHF radio or via the internet. Some geographic regions have established GPS networks (referred to as NTRIP) that can be accessed with login credentials. This Quick Reference Guide helps users configure the internal UHF radio of the C321 to receive RTK corrections from a nearby Base Station broadcasting RTK corrections over UHF radio. Another option helps users configure the C321 to receive RTK corrections from a network. First, connect to the C321. Click on Tools -> Advanced Tools -> Configure Rover. The first time you use the software, the following dialogue displays: SiteMetrix Configuring RTK QRG Page 1 of 24
Click GPS Simulation, and scroll over to the Hemisphere tab. Select C321. Most applications require a Bluetooth connection to the C321. Click Type: Serial Port and toggle to Type: Bluetooth. SiteMetrix Configuring RTK QRG Page 2 of 24
Click Remote Device: None. The following dialogue displays. Click Find Receiver. The software searches for nearby Bluetooth devices. Note: The Bluetooth searches for and lists all nearby Bluetooth devices. Click of the C321 serial number, press OK. SiteMetrix Configuring RTK QRG Page 3 of 24
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Click Settings. To connect to a GPS network using your computer/tablet internet connection verify Update Rate is at least 2Hz. SiteMetrix Configuring RTK QRG Page 5 of 24
Click RTK. Most scenarios use one of three connection options. Connect to a GPS Base by: 1) Placing a SIM card into the C321 2) Accessing the internet from a tablet 3) Connecting to a nearby GPS base station via UHF radio Note: Other configurations are available. If the above three do not describe your purposes, please contact your local Hemisphere GNSS dealer for technical support. SiteMetrix Configuring RTK QRG Page 6 of 24
To connect to an NTRIP network using the internal SIM card in the C321, choose RTK Port Type: Internal, select RTK Device: Internal GSM, then select RTK Network: NTRIP. SiteMetrix Configuring RTK QRG Page 7 of 24
Click Radio. Click Advanced Configuration. SiteMetrix Configuring RTK QRG Page 8 of 24
Click APN. Toggle through APN Provider until you reach your SIM card provider. Verify the APN Server, username, and password (this information can be obtained from your provider). To change a value, click the box next to the value. Note: the SIM card must be configured for data (ask your provider for a SIM card configured for a tablet). Press OK. SiteMetrix Configuring RTK QRG Page 9 of 24
Next, click NTRIP. SiteMetrix Configuring RTK QRG Page 10 of 24
Click NTRIP Caster: NtripInfoCaster. SiteMetrix Configuring RTK QRG Page 11 of 24
Click Add New Entry, and select a name. Type the host (either an IP address or DNS), port, username, and password, then click Download Bases. SiteMetrix Configuring RTK QRG Page 12 of 24
Press OK. Your C321 is now configured to receive corrections from NTRIP. Note: If you click Download Bases and receive an error message, check your internet connection, your APN information, and ensure the cellular antenna is screwed into the correct port on the C321. Verify you used the correct login credentials for the NTRIP caster. To connect to an NTRIP network using the internet on your tablet/computer, click RTK. Set the following: RTK Port Type: DC Radio/DC Internet RTK Device: Data Collector Internet RTK Network: NTRIP SiteMetrix Configuring RTK QRG Page 13 of 24
Click Radio. Set Output Port: Data. SiteMetrix Configuring RTK QRG Page 14 of 24
Click NTRIP and follow the instructions above for typing in credentials for NTRIP caster. To use the internal UHF radio, click RTK. Set the following: RTK Port Type: Internal RTK Device: Internal UHF SiteMetrix Configuring RTK QRG Page 15 of 24
Click Radio. SiteMetrix Configuring RTK QRG Page 16 of 24
Click Advanced Configuration. SiteMetrix Configuring RTK QRG Page 17 of 24
Select the Protocol: and Channel: Note: Only a certified HGNSS dealer can enter channels into the UHF radio. If you do not have the correct UHF frequency, please contact your local dealer for a channel table. The channel table provides the channels and the channel spacing you can use for each channel (For example: Channel 1: 469.55 MHz with a channel spacing of 25.0 KHz and then Channel 2: 469.55 MHz with a channel spacing of 12.5 KHz; is configured by your dealer depending on the licensing and regulations of your geographic region). The available protocol is dependent on the channel spacing of your current channel. If your current channel is set for 25.0 KHz channel spacing, then only wideband protocols display. For the definition of each protocol, please see the chart below: SiteMetrix Configuring RTK QRG Page 18 of 24
Click OK. Your C321 is configured for UHF radio. WARNING: if you re not receiving RTK corrections, please check to ensure the UHF antenna is screwed into the UHF slot (and not the GSM antenna slot) the settings of the base UHF match the settings of the C321 UHF). Troubleshooting: Internal UHF if are not receiving corrections, check the front display panel to verify the internal UHF radio is receiving data. A green light (as shown below) indicates the UHF radio is the selected RTK device. The light blinks each time an RTK connection is received (once per second). Note: If the light is not blinking, first check to see if the UHF antenna is connected to the SMA connector on the C321 (and not the GSM connector). Then, verify your base station is outputting RTK corrections. Most base stations or base station radios have a transmit (Tx) light that blinks when the base station outputs an RTK correction (about once per second). If RTK corrections are being sent by the base station, but the UHF LED light still indicates the C321 is not receiving RTK messages, there is probably a frequency, protocol, modulation, or forward error correction mismatch. Verify all SiteMetrix Configuring RTK QRG Page 19 of 24
the settings on the base station UHF radio match the settings on the rover UHF radio. Internal GSM* If you are not receiving RTK over the Internal GSM modem, verify the GSM LED is illuminated (as shown below). The Internal GSM light should blink each time an RTK message is received (about once per second). SiteMetrix Configuring RTK QRG Page 20 of 24
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Note: If the Internal GSM If the light is not blinking, confirm the GSM antenna is connected to the GSM SMA connector at the bottom of the C321 (refer to picture above). Verify the GSM antenna is not connected to the UHF port and the UHF antenna is not connected to the GSM port. After verifying the correct antenna is connected to the correct port, use the function (FN) button to scroll to the Device Status screen on the front panel of the C321. SiteMetrix Configuring RTK QRG Page 22 of 24
Verify the Cellular Signal Quality (CSQ) is not blank. Note: If the CSQt is blank, there is no internet. Ensure the SIM card is active and verify you entered the correct APN, username, and password. If you have verified that the C321 is online, but you are not receiving corrections, verify the correct NTRIP credentials were used. Note:The NTRIP network may be experiencing downtime. *the above assumes there is adqeuate cellular reception. SiteMetrix Configuring RTK QRG Page 23 of 24
Data Collector Internet* if you re using internet on your data collector, exit SiteMetrix and go to the Windows desktop. Open a web browser to access a website. If you cannot access a website your data collector is offline. Check the Wi-Fi or SIM card settings. If your data collector is online, verify the login credentials for the NTRIP caster. *the above assumes adequate internet availability. Hemisphere GNSS Inc. 8515 E. Anderson Drive Scottsdale, AZ 85255, USA Phone: +1 480 348 6380 Fax: +1 480 270 5070 precision@hgnss.com www.hgnss.com SiteMetrix Configuring RTK QRG Page 24 of 24