OEMV Family Installation and Operation User Manual OM-20000093 Rev 5B
Proprietary Notice OEMV Family Installation and Operation User Manual Publication Number: Revision Level: Revision Date: OM-20000093 5B 2007/03/23 Proprietary Notice Information in this document is subject to change without notice and does not represent a commitment on the part of NovAtel Inc. The software described in this document is furnished under a licence agreement or non-disclosure agreement. The software may be used or copied only in accordance with the terms of the agreement.
Table of Contents Table of Contents Table of Contents Notice Software License Warranty Customer Service Foreword 1 Introduction 3 10 15 17 18 19 20 1.1 Overview of the OEMV Family.............................................................................. 20 1.1.1 Common Features....................................................................................... 20 1.2 OEMV Cards......................................................................................................... 21 1.2.
Table of Contents 3.3.2 Universal Serial Bus (USB)......................................................................... 45 3.3.3 CAN Bus ..................................................................................................... 46 3.3.4 Status Indicators ......................................................................................... 47 3.3.5 DL-V3 Status Indicators .............................................................................. 48 3.3.
Table of Contents 6.2 CDU ...................................................................................................................... 99 6.3 Convert ............................................................................................................... 105 6.3.1 Rinex Format ............................................................................................. 105 6.3.2 Convert Command Line Switches ............................................................. 107 6.
Table of Contents Cables ............................................................................................................... 175 SMART-V1 .............................................................................................................. 179 Port Pin-Outs .................................................................................................... 181 Optional Cables ................................................................................................
Figures 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 Primary and Secondary Lightning Protection ................................................................... 12 OEMV-1 Card ................................................................................................................... 21 OEMV-1G Card ................................................................................................................
47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 8 OEMV-1 Board Dimensions ........................................................................................... 130 Top-view of 20-Pin Connector on the OEMV-1 .............................................................. 135 OEMV-1G Board Dimensions ........................................................................................ 136 Top-view of 20-Pin Connector on the OEMV-1G ...........
Tables 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Enclosure Features Comparison................................................................................ 25 NovAtel GNSS Antenna Models ................................................................................ 34 Voltage Input Range for OEMV.................................................................................. 35 Enclosure Power Requirements..............
Notice Notice The following notices apply to the DL-V3, ProPak-V3, FlexPak-V2, FlexPak-V1G, FlexPak-V1, and SMART-V1. An OEMV card might not pass emissions testing by itself. For example, the ProPak-V3 passes regulatory emissions as shown in this Notice. For more information on emissions testing, please refer to the regulatory body in your geographic area. For example, in the US that is the Federal Communications Commission (FCC) and in Europe the Conformité Européenne (CE).
Notice CE NOTICE The enclosures carry the CE mark. WARNING: This is a Class A product. In a domestic environment this product may cause radio interference in which case the user may be required to take adequate measures. "Hereby, NovAtel Inc. declares that this DL-V3, ProPak-V3, FlexPak-V2, FlexPak-V1G, FlexPak-V1 and SMART-V1 is in compliance with the essential requirements and other relevant provisions of Directive 1999/5/EC.
Notice Lightning Protection Notice What is the hazard? A lightning strike into the ground causes an increase in the earth's potential causing a high voltage potential between the centre conductor and shield of the coax cable. Voltages directly applied onto the centre conductor "roll off" and arrive after the shield pulse producing a high voltage potential between the centre conductor and shield of the coax cable.
Notice Electromagnetic Compatibility (EMC) and Safety Regulatory Testing (DL-V3) • • • • FCC, Part 15 Radiated Emissions, Class A EN 55022 Emissions, Class A EN 55024 Immunity • EN 61000-4-2 Electrostatic Discharge Immunity • EN 61000-4-3 Radiated RF EM Field Immunity Test • EN 61000-4-4 Electrical Fast Transient/Burst Test • EN 61000-4-6 Conducted Immunity • EN 61000-4-8 Magnetic Field Immunity EN 60950 Safety of Information Technology Equipment Regulatory Testing (ProPak-V3) • • • • FCC, Part 15 Rad
Notice WEEE Notice If you purchased your OEMV family product in Europe, please return it to your dealer or supplier at the end of its life. The objectives of the European Community's environment policy are, in particular, to preserve, protect and improve the quality of the environment, protect human health and utilise natural resources prudently and rationally. Sustainable development advocates the reduction of wasteful consumption of natural resources and the prevention of pollution.
Software License Software License BY INSTALLING, COPYING, OR OTHERWISE USING THE SOFTWARE PRODUCT, YOU AGREE TO BE BOUND BY THE TERMS OF THIS AGREEMENT. IF YOU DO NOT AGREE WITH THESE TERMS OF USE, DO NOT INSTALL, COPY OR USE THIS ELECTRONIC PRODUCT (SOFTWARE, FIRMWARE, SCRIPT FILES, OR OTHER ELECTRONIC PRODUCT WHETHER EMBEDDED IN THE HARDWARE, ON A CD OR AVAILABLE ON THE COMPANY WEB SITE) (hereinafter referred to as "Software"). 1. License: NovAtel Inc.
Software License ware from unauthorized disclosure or use. 5. Term and Termination: This Agreement and the rights and licences hereby granted shall continue in force in perpetuity unless terminated by NovAtel or Licensee in accordance herewith.
Warranty Warranty NovAtel Inc.
Customer Service Customer Service Firmware upgrades are firmware releases, which increase basic functionality of the receiver from one model to a higher level model type. When available, upgrades may be purchased at a price, which is the difference between the two model types on the current NovAtel Inc. Price List plus a nominal service charge. Firmware upgrades are accomplished through NovAtel authorized dealers. Contact your local NovAtel dealer first for more information.
Foreword Foreword Thank you for purchasing a NovAtel receiver card. Whether it is stand-alone or in an enclosure, this manual will help you get the hardware operational and provide further general information. Afterwards, the OEMV Firmware Reference Manual will be your primary OEMV family command and logging reference source.
Chapter 1 1.1 Introduction Overview of the OEMV Family The OEMV family offers single, dual and triple-frequency GNSS receivers and the first integrated Lband capability without the need for a separate board. The OEMV-based products are GLONASSenabled and are capable of full code and real-time kinematic (RTK) positioning.
Introduction 1.2 Chapter 1 • An extensive command and log set for maximum customization • Outputs to drive external LEDs OEMV Cards The OEMV family cards consist of a single printed circuit board with integrated radio frequency (RF) and digital sections. They are designed for flexibility of integration and configuration.
Chapter 1 1.2.2 Introduction OEMV-1G Card The OEMV-1G is a compact, low-power, single frequency L1 GPS card with integrated GLONASS L1. In addition to the functionality given in Section 1.1.1 on Page 20 and Section 1.2.
Introduction Chapter 1 Figure 4: OEMV-2 Card 1.2.4 OEMV-3 Card The OEMV-3 is a GPS L1/L2/L5 plus GLONASS L1/L2 card that is a drop-in replacement for the OEM4-G2. Triple-frequency capabilities will make the following possible: longer baselines in differential positioning mode due to the reduction of atmospheric errors, faster resolution of carrierphase ambiguities when performing RTK positioning and enhanced positioning precision due to the additional measurements.
Chapter 1 Introduction • Increased memory size and processor speed • Optional Application Program Interface (API) software for loading a custom application Included with the OEMV is a wrist-grounding strap to prevent ESD damage when handling the card and a CD containing NovAtel’s PC utilities and product documentation. For technical specifications on the OEMV-3 please see Section A.5 starting on Page 148.
Introduction 1.3 Chapter 1 OEMV-Based Enclosures The OEMV-3 can be housed in a DL-V3 or ProPak-V3 enclosure to provide a complete receiver solution. The OEMV-2, OEMV-1 and OEMV-1G cards can be housed in a FlexPak. The OEMV-1 card can also be housed in a SMART-V1. When connected to an antenna and a power source, the enclosure and associated OEMV card together form a fully functioning GNSS receiver. The enclosures offer protection against environmental conditions and RF interference.
Chapter 1 1.3.1 Introduction ProPak-V3 and DL-V3 The features of the OEMV-3 are available within the DL-V3 and ProPak-V3. These enclosures, see Figure 6 below, offer GNSS integrators an effective, self-contained system for indoor applications while also providing a rugged, water, shock, and vibration resistant housing for outdoor applications. The DL-V3 is also capable of data logging (DL) using the removable Compact Flash (CF) card.
Introduction Chapter 1 • straight through serial • null modem serial • I/O • 12 V power cable • A CD containing NovAtel’s PC utilities and product documentation For technical specifications on the DL-V3, please see Section A.6 starting on Page 156.
Chapter 1 1.3.2 Introduction FlexPak NovAtel's FlexPak is a rugged, waterproof housing for the OEMV-2, OEMV-1G or OEMV-1 engine. As a result, the FlexPak can deliver centimeter-level positioning in a compact, lightweight enclosure. The FlexPak-V2 provides dual-frequency positioning with a USB interface and an API option for supporting custom applications. Each FlexPak receiver has two SBAS channels. FlexPak-V1G is a GPS + GLONASS model.
Introduction 1.3.3 Chapter 1 SMART-V1 NovAtel’s SMART-V1 is a rugged, self-contained GPS receiver and antenna. It is specially designed for harsh tracking environments in a number of applications. The SMART is available in two side-mount configurations to suit your integration requirements: USB or CAN.
Chapter 2 Receiver System Overview In addition to a NovAtel OEMV card, a complete GNSS receiver system typically contains four other major components: • A custom enclosure and wiring harness • A GNSS antenna (and optional LNA power supply) • A power supply • Data communications equipment The overall system is represented in Figure 9. A brief description of the Radio Frequency (RF) and Digital Electronics sections follow the figure. The components above are also described.
Receiver System Overview 9 10 11 12 13 2.1 32-Bit CPU System I/O AGC Clock VCTCXO Chapter 2 22 23 24 25 26 Input Timing Signal Output Timing Signal USB Communication CAN Communication 1 CAN Communication 2 OEMV Card NovAtel’s OEMV cards consist of a radio frequency (RF) and a digital electronics section. 2.1.1 Radio Frequency (RF) Section The receiver obtains a filtered and amplified GNSS signal from the antenna via the coaxial cable.
Chapter 2 2.3.1 Receiver System Overview Optional LNA Power Supply Power for the antenna LNA is normally supplied by the receiver but not, for example, by the OEMV2 card. If a different type of antenna is required that is incompatible with this supply, then you could connect an external power source to the receiver. See also Antenna LNA Power on Page 51. 2.4 Principal Power Supply A single external power supply capable of delivering the minimum receiver voltage necessary to operate the receiver.
Chapter 3 Installation and Set Up This chapter contains instructions and tips to set up your NovAtel receiver to create a GNSS receiver system similar to that described in Chapter 2, Receiver System Overview on Page 30. 3.
Chapter 3 Installation and Set Up Table 2: NovAtel GNSS Antenna Models Models 3.1.
Installation and Set Up Chapter 3 OEMV Cards The OEMV card contains a DC to DC converter that is very tolerant to noise and ripple at its input. A tightly regulated input supply to the OEMV-3 card is not required, as long as it falls within the given input range. A tightly regulated input supply to the OEMV-1, OEMV-1G or OEMV-2 card is required. The power supply used for any OEMV card should be capable of 5 W. The voltage input range for each the OEMV cards is given in Table 3 on Page 35.
Chapter 3 3.2 Installation and Set Up Installation Overview Once you have selected the appropriate equipment, complete the following steps to set up and begin using your NovAtel GNSS receiver. 1. Install the OEMV card in an enclosure with a wiring harness, as described in Section 3.2.1 on Page 36. 2. Mount the GNSS antenna to a secure, stable structure, as described in Section 3.2.3 on Page 39. 3.
Installation and Set Up Chapter 3 • Failure to follow accepted ESD handling practices could cause damage to the OEMV card. • Warranty may be voided if equipment is damaged by ESD. Mounting the Printed Circuit Board The OEMV family cards are OEM products and therefore the printed circuit board is provided without a housing structure. This allows flexibility in creating a mounting environment to suit particular product and marketing requirements.
Chapter 3 Installation and Set Up 1 3 2 Figure 10: OEMV-1 and OEMV-1G Connector and Indicator Locations .
Installation and Set Up Chapter 3 4 2 3 1 5 Figure 12: OEMV-3 Connector and Indicator Locations Reference 3.2.2 Description 1 P1601 power, data, and signal connector (40 pin dual row male connector with 0.025” square pins and 0.
Chapter 3 Installation and Set Up information. When installing the antenna system: 3.2.4 • Choose an antenna location that has a clear view of the sky so that each satellite above the horizon can be tracked without obstruction. (Refer to the Multipath section in the GPS+ Reference Manual). • Mount the antenna on a secure, stable structure capable of safe operation in the specific environment.
Installation and Set Up Chapter 3 pressed on a handheld data logger that is plugged into one of the DL-V3's serial ports, the time required to come on is only a few seconds. However, it may require an additional few minutes to establish an initial time and position. During power-down and power-up time, the serial ports do not process data. You must wait until the receiver outputs an RXSTATUSA log with a BOOTOK message before typing any commands.
Chapter 3 Installation and Set Up Table 6: SMART-V1 Port Configuration (RS-232 only) Model Ports USB The single port on the USB model of the SMART-V1 can be used for COM1, COM2 or USB CAN The single port on the CAN model of the SMART-V1 can be used for COM1, CAN or COM3 Each port may support some, or all, of the following signals: • Data Terminal Ready (DTR) • Clear To Send (CTS) • Transmitted Data (TXD) • Request To Send (RTS) • Received Data (RXD) • Data Carrier Detect (DCD) On many of
Installation and Set Up Chapter 3 Table 7: SMART-V1 Cable Options (RS-232 only) Model Cables USB SMART-V1 COM1/COM2/USB 01017893 USB: DB9: SMART-V1 Variant 01017923 Bare tagged wire: USB COM1 COM2 PWR PWR2 GND GND2 RESERVED TIMEMARK DIGITAL GND SMART-V1 COM1/CAN/COM3 01017894 DB9: SMART-V1 Variant 01017922 Bare tagged wire: CAN1 COM3 COM1 PWR PWR2 GND GND2 RESERVED TIMEMARK DIGITAL GND CAN Part Numbers Connector Ends USB plug COM1 female COM2 female Bare tagged wire: PWR PWR2 GND GND2 RES
Chapter 3 Installation and Set Up V3 COM3 Configuration starting on Page 44. The OEMV-3 offers a user-selectable configuration for the COM1 port. For OEMV-3, the configuration is selected using the USERIO1 pin. By default, RS-232 is selected as the USERIO1 input is set LOW by an internal pull-down resistor. To select RS-422 upon startup, apply 3.3 V to USERIO1. Alternatively, tie USERIO1 to pin 38 of the 40-pin connector on the OEMV-3.
Installation and Set Up Chapter 3 • FlexPak-V1/V1G/V2 port pin-out starting on Page 173 • SMART-V1 port pin-out on Page 181 3.3.2 Universal Serial Bus (USB) OEMV family receivers, along with the accompanying NovAtel USB drivers for Windows 2000 and Windows XP, provide three virtual serial ports over a single USB 1.1 connection using USB D(+) and USB D(-) signals, see Table 8 below.
Chapter 3 3.3.3 Installation and Set Up CAN Bus A Controller Area Network Bus (CAN Bus) is a rugged differential serial bus with a protocol that provides services for processes, data and network management. CAN Bus is a generic term, as well as referring to a specific standard for several rugged differential bus standards that provide services for processes, data, and network management.
Installation and Set Up Chapter 3 Table 9: Available CAN Signals on Receivers Receiver OEMV-1 and OEMV-1G (no transceiver) J700 Pins/Ports CAN1 Tx Pin 7 CAN1 Rx Pin 6 CAN2 Tx Pin 20 CAN2 Rx Pin 8 OEMV-2 (no transceiver) P1100 CAN1 Tx Pin 19 CAN1 Rx Pin 7 OEMV-3 (with transceiver) P1400 CAN1H Pin 2 CAN1L Pin 1 CAN2H Pin 6 CAN2L Pin 5 CANH Pin 3 CANL Pin 4 SMART-V1 3.3.
Chapter 3 Installation and Set Up Table 11: FlexPak Status Indicators 3.3.
Installation and Set Up Chapter 3 COM3 The COM3 section of the LED panel on the front of the DL-V3, has two LEDs: • 1 for Bluetooth Mode (default) • 1 for Ethernet Mode Only one mode may be used at a time on COM3. The active mode’s LED glows (blue for Bluetooth and orange for Ethernet). See also Appendix C, Ethernet Configuration starting on Page 189.
Chapter 3 Installation and Set Up Positioning Mode Which LEDs are glowing, or blinking, or off, and their colors, correspond to the DL-V3’s current positioning mode. Table 14 below shows the available positioning modes and their corresponding LEDs where the first LED to the left is #1, as you look at the DL-V3, and #5 is the furthest to the right. If the table cell shows the name of a color (red, amber or green) with a solid background, that LED is glowing solidly.
Installation and Set Up Chapter 3 Occupation Time The LED that is glowing green corresponds to the DL-V3’s occupation time gauge. The occupation time LEDs provide an indication of whether sufficient data has been collected for successfully post processing data for the indicated baseline. The LED that appears corresponds to the baseline length that you can process your data to, where the first LED to the left is #1.
Chapter 3 Installation and Set Up The OEMV family receivers and their LNA capabilities are listed in this section. OEMV-3 For the OEMV-3 it is possible to supply power to the LNA of an active antenna either from the antenna port of the OEMV-3 card itself or from an external source. The internal antenna power supply of the OEMV-3 cards can produce +4.75 to +5.10 V DC at up to 100 mA; enough for NovAtel’s dualfrequency GNSS antennas, so that an additional LNA power supply is not normally required.
Installation and Set Up Chapter 3 An example of a 64 MB CF card is shown in Figure 13 below. Figure 13: 64 MB Flash Card When you insert a CF card into the DL-V3, enter a DISK FORMAT command using the Console window in NovAtel’s Control and Display Unit (CDU) graphical user interface software. Wait a few minutes and use the DL-V3 power button to turn it off and then on again. When power is returned, the DL-V3 should be able to recognize and use the CF card. For more information on CDU see Section 6.
Chapter 3 Installation and Set Up 1 Figure 14: Compact Flash Card Door (shown with its latch in the open position) To remove the CF card, unlock the access door. When the door is open, you can see an eject button to the left of the card. You must push this button to partially eject the card. Grasp the card and pull it all the way out. WARNING: Do not change the card while logging is in progress. Data will be lost.
Installation and Set Up Chapter 3 example: #VERSIONA,COM1,0,75.0,UNKNOWN,0,1608.685,004c0000,3681,2678; 3,GPSCARD,"L12LGRVA","DAB06420097","OEMV3G-3.02-2T2","3.200A10","3.000", "2007/Feb/20","11:44:36",DB_USERAPPAUTO,"DL-V3","0","","1.000A16","", "2007/Jan/03","17:39:23",USERINFO,"LMX9820A","0623","","","","","" *c2605fb9 4. Insert the CF card. 5. Type DISK FORMAT in the terminal program and press the key. 6. Wait a minute and power off the DL-V3. 7.
Chapter 4 Operation Before operating the receiver for the first time, please ensure that you have followed the installation instructions in Chapter 3, Installation and Set Up on Page 33. The following instructions are based on a configuration such as that shown in Figure 15 below. It is assumed that a personal computer is used during the initial operation and testing for greater ease and versatility.
Operation 4.1 Chapter 4 Communications with the Receiver Communication with the receiver typically consists of issuing commands through the communication ports from an external serial communications device. This could be either a terminal or an IBMcompatible PC that is directly connected to the receiver serial port using a null modem cable. If you are using an RTK radio it connects to the receiver’s COM port by means of the radio serial cable supplied with the receiver.
Chapter 4 4.2 Operation Getting Started Included with your receiver are NovAtel’s CDU and Convert programs. CDU is a windows-based GUI which allows you to access the receiver's many features without the need for communications protocol or to write special software. The Convert utility is a windows-based utility that allows you to convert between file formats, and strips unwanted records for data file compilation.
Operation Chapter 4 or [COM3] if connected to COM3 port Any of the above prompts indicate that the receiver is ready and waiting for command input. The screen may display other port names for other port types, for example USB1, USB2, USB3 or AUX. 1. You may also have to wait for output from receiver self tests. For example, on start-up, the OEMV family receiver is set to log the RXSTATUSEVENTA log ONNEW on all ports. See Section 7.4, RXSTATUSEVENT Log on Page 119 for more details. 2.
Chapter 4 4.3 Operation Transmitting and Receiving Corrections Corrections can be transmitted from a base station to a rover station to improve position accuracy. The base station is the GNSS receiver which is acting as the stationary reference. It has a known position and transmits correction messages to the rover station. The rover station is the GNSS receiver which does not know its exact position and can be sent correction messages from a base station to calculate differential GNSS positions.
Operation Chapter 4 of data throughput at a rate of 9600 bits per second, and less than 4.0 s latency, is recommended. Once your base and rover are set up, you can configure them as shown in the configuration examples that follow in Sections 4.3.1 - 4.3.2 starting on Page 62. 4.3.
Chapter 4 Operation log com2 cmrobs ontime 1 log com2 cmrref ontime 10 log com2 cmrdesc ontime 10 1 4.3.2 Rover Station Configuration At the rover station, enter: interfacemode port rx_type tx_type [responses] For example: RTCA interfacemode com2 rtca none off RTCM interfacemode com2 rtcm none off RTCMV3 interfacemode com2 rtcmv3 none off CMR+ interfacemode com2 cmr none off CMR interfacemode com2 cmr none off 4.3.
Operation Chapter 4 commands when the rover station is receiving corrections from multiple base stations. See Section 5.2, Satellite-Based Augmentation System (SBAS) on Page 78 for more information on SBAS. All PSRDIFFSOURCE entries fall back to SBAS (even NONE) for backwards compatibility. At the base station it is also possible to log out the contents of the standard corrections in a form that is easier to read or process.
Chapter 4 Operation 1. Select the Group Ensure your antenna is in the correct position on the base or rover. DLVTool is available from our website at: http:// www.novatel.com/support/fwswupdates.htm. The the DL-V3 captures sets of logs using log groups. You create a group in DLVTool and then upload the group to the DL-V3. Launch DLVTool from the Start menu folder specified during the installation process. The default location is Start | Programs | NovAtel OEMV | DLVTool. Select the Group Editor button.
Operation 4.5 Chapter 4 Enabling SBAS Positioning All OEMV family receivers are capable of SBAS positioning. This positioning mode is enabled using the SBASCONTROL command. EGNOS at one time used the IGNOREZERO test mode. At the time of printing, ZEROTOTWO is the correct setting for all SBAS, including EGNOS, running in test mode. On a simulator, you may want to leave this parameter off or specify NONE explicitly.
Chapter 4 Operation To confirm you are tracking an L-Band signal, log the L-Band status information by entering the following command: log lbandstat For example, if you are receiving CDGPS, the fifth field after the header should be 00c2: lbandstat com1 0 43.5 finesteering 1295 149951.671 00000000 976f 34461 <1547546977 46.18 4541.0 0.00 00c2 00f0 0 0 0 8070 0001 0 0 0 Please refer to the LBANDSTAT command for details. 4.
Operation Chapter 4 (by at least 5 ns) Figure 17: OEMV-3 and ProPak-V3 T Sync 5 MHz and 1PPS OEMV Family Installation and Operation User Manual Rev 5B 67
Chapter 4 Operation (by at least 5 ns) Figure 18: FlexPak-V2 T Sync 5 MHz and 1PPS 68 OEMV Family Installation and Operation User Manual Rev 5B
Operation Chapter 4 (by at least 5 ns) Figure 19: OEMV-3 and ProPak-V3 T Sync 10 MHz and 1PPS OEMV Family Installation and Operation User Manual Rev 5B 69
Chapter 4 Operation (by at least 5 ns) Figure 20: FlexPak-V2 T Sync 10 MHz and 1PPS 4.9 Transferring Time Between Receivers The ADJUST1PPS command is used to as part of the procedure to transfer time between receivers. The number of pulses per second (PPS) is always set to 1 Hz with this command. It is typically used when the receiver is not adjusting its own clock and is using an external reference frequency. The TIMESYNC log is also used to synchronize time between receivers.
Operation 4.9.1 Chapter 4 GPS to Receiver Time Synchronization Synchronization of receiver time with GPS time does not occur until the receiver locks onto its first satellite. The GPS L1 signal has two main streams of data modulated on the carrier. These data streams are the C/A code (1.023 MHz rate) and the P(Y) code (10.23 MHz rate). Additionally, a navigation message (at a 50 Hz rate) contains GPS satellite data including the ephemeris, clock corrections and constellation status.
Chapter 4 Operation The section that follows gives procedures for transferring time from a Fine Clock receiver to a Cold or Warm Clock receiver. 4.9.3 Procedures to Transfer Time These procedures are to transfer time between a Fine Clock and a Cold or Warm Clock GPS receiver. Transfer COARSE time (<10 ms) from a Fine Clock to a Cold Clock GPS receiver 1. Connect a COM port from the Fine Clock to the Cold Clock (for example, COM2 on the Fine Clock receiver to COM3 on the Cold Clock receiver).
Operation Chapter 4 The phase of the Warm Clock receiver clock is adjusted by the fractional measurement of the Fine Clock receiver’s 1PPS mark input event. In other words, it synchronizes the Warm Clock receiver’s 1PPS to the incoming 1PPS of the Fine Clock receiver. It does NOT adjust the 1 second Time of Week (TOW) counter or the receiver's Week Number. This procedure is used to make small corrections to the Warm Clock receiver’s clock.
Chapter 5 Positioning Modes of Operation NovAtel's dual frequency GNSS receivers have several important performance advantages depending on your positioning requirements. Dual frequency allows direct measurement of the signal delay through the ionosphere and is critical to fast and reliable integer ambiguity resolution when positioning using carrier measurements. Dual frequency can improve the performance of DGPS, SBAS, and RTK positioning.
Positioning Modes of Operation Chapter 5 By averaging many GPS measurement epochs over several hours, it is possible to achieve a more accurate absolute position. This section attempts to explain how the position averaging function operates and to provide an indication of the level of accuracy that can be expected versus total averaging time. The POSAVE command implements position averaging for base stations.
Chapter 5 Positioning Modes of Operation Figure 22: Single-Point Averaging (Typical Results) Figure 23: Single-Point Averaging (Typical Results with WAAS) 76 OEMV Family Installation and Operation User Manual Rev 5B
Positioning Modes of Operation Chapter 5 The position averaging function is useful for obtaining the WGS84 position of a point to a reasonable accuracy without having to implement differential GPS. It is interesting to note that even a six hour occupation can improve single-point GPS accuracy from over 1.5 meters to better than a meter. This improved accuracy is primarily due to the reductions of the multipath errors in the GPS signal.
Chapter 5 Positioning Modes of Operation and so on). However, because a receiver makes all of its single-point pseudorange measurements using the same common clock oscillator, all measurements are equally offset, and this offset can generally be modeled or quite accurately estimated to effectively cancel the receiver clock offset bias. Thus, in single-point positioning, receiver clock offset is not a significant problem. • 5.
Positioning Modes of Operation Chapter 5 SBAS and NovAtel Worldwide EGNOS: Europe (2001-2002) • 24 RIMS-C receivers (Integrity Channel) SNAS China (2000-2002) • 73 WAAS WRS receivers MSAS: Japan (1998-2003) • 47 MSAS WRS receivers • 6 NLES GUS receivers • 4 UPC receivers WAAS: USA (1996-1999) 1st Generation • 148 WRS receivers • 21 GUS receivers WAAS G-II Receivers Technology Refresh (2004-2006) • 160 WAAS G-II receivers Geostationary Command & Control Segment (2004-2006) • 13 L1/L5 Signal Generators •
Chapter 5 Positioning Modes of Operation 1 2 3 5 4 6 8 9 9 7 11 9 7 10 Figure 25: The SBAS Concept Reference 1 2 3 4 5 6 7 5.2.1 Description Reference Geostationary Satellite (GEO) GPS Satellite Constellation L1 L1 and C-Band L1 and L2 GPS User Integrity data, differential corrections and ranging control 8 9 10 11 Description C-Band SBAS Reference Station SBAS Master Station Ground Uplink Station SBAS Receiver All models of NovAtel OEMV receivers are equipped with SBAS capability.
Positioning Modes of Operation Chapter 5 benefits with no subscription fee. 5.2.2 SBAS Commands and Logs The command SBASCONTROL, enables the use of the SBAS corrections in the position filter. In order to use this command, first ensure that your receiver is capable of receiving SBAS corrections. Several SBAS specific logs also exist and are all prefixed by the word WAAS except for the RAWWAASFRAME log.
Chapter 5 5.3.2 Positioning Modes of Operation Position Solutions Due to the many different applications for differential positioning systems, two types of position solutions are possible. NovAtel’s carrier-phase algorithms can generate both matched and low-latency position solutions, while NovAtel’s pseudorange algorithms generate only low-latency solutions. These are described below: 1.
Positioning Modes of Operation 5.3.3 Chapter 5 Dual Station Differential Positioning It is the objective of operating in differential mode to either eliminate or greatly reduce most of the errors introduced by the system biases discussed in Section 5.1.1, GPS System Errors starting on Page 77.
Chapter 5 Positioning Modes of Operation 1 2 3 4 5 6 7 8 9 Figure 26: Typical Differential Configuration Reference 1 2 3 4 5 6 Description Reference GPS Constellation Radio Data Link GPS Antenna with Choke Ring Modem Differential Corrections Input Differential Corrections Output 7 8 9 Description GPS Receiver Base Station Rover Station The Rover Station A rover station is generally any receiver whose position is of unknown accuracy, but has ties to a base station through an established data l
Positioning Modes of Operation 5.4 Chapter 5 L-Band Positioning The transmission of OmniSTAR or CDGPS corrections are from geostationary satellites. The L-Band frequency of geostationary satellites is sufficiently close to that of GPS that a common, single antenna, such as the NovAtel GPS-702L, may be used. Both systems are portable and capable of sub-meter accuracy over their coverage areas. See also Figure 29, L-Band Concept on Page 89.
Chapter 5 Positioning Modes of Operation Canada/America-Wide CDGPS In order to enable CDGPS positioning, you must set the L-Band frequency for the geographically appropriate CDGPS signal using the ASSIGNLBAND command. See also Section 5.4.3, L-Band Commands and Logs starting on Page 90 for information on this command. The CDGPS signal is broadcast on 4 different spot beams on the MSAT-1 satellite.
Positioning Modes of Operation Chapter 5 Figure 28 on Page 87 is a conservative map of the coverage areas that CDGPS guarantee. The coverage may be better in your area. Figure 28: CDGPS Percentage (%) Coverage Map In Figure 28, 100% coverage means that a correction is received for every visible satellite (at or above 10 degrees). 90% coverage means that a correction is received for 90% of visible satellites.
Chapter 5 5.4.
Positioning Modes of Operation Chapter 5 6 1 1 7 5 4 3 8 2 3 2 3 2 Figure 29: L-Band Concept Reference 1 2 3 4 5 6 7 8 Description GPS satellites Multiple L-Band ground stations Send GPS corrections to 4 Network Control Center where data corrections are checked and repackaged for uplink to 6 DGPS uplink L-Band geostationary satellite L-Band DGPS signal Correction data are received and applied real-time OEMV Family Installation and Operation User Manual Rev 5B 89
Chapter 5 5.4.3 Positioning Modes of Operation L-Band Commands and Logs The ASSIGNLBAND command allows you to set OmniSTAR or CDGPS base station communication parameters. It should include a relevant frequency and data rate, for example: assignlband omnistar 1536782 1200 or, assignlband cdgps 1547547 4800 The PSRDIFFSOURCE command lets you identify from which source to accept RTCA1, RTCM1, CDGPS or OmniSTAR VBS differential corrections.
Positioning Modes of Operation 5.5 Chapter 5 Carrier-Phase Differential Carrier-phase algorithms monitor the actual carrier wave itself. These algorithms are the ones used in real-time kinematic (RTK) positioning solutions - differential systems in which the rover station, possibly in motion, requires base-station observation data in real-time. Compared to pseudorange algorithms, much more accurate position solutions can be achieved: carrier-based algorithms can achieve accuracies of 1-2 cm (RMS).
Chapter 5 5.5.1 Positioning Modes of Operation Real-Time Kinematic (RTK) RT-2 (OEMV-2 and OEMV-3 with AdVance RTK) and RT-20 (OEMV-1 and OEMV-1G) are real-time kinematic software products developed by NovAtel. They can only be used in conjunction with NovAtel GPS receivers. A quick comparison of RT-2 and RT-20 is shown in Table 17 below.
Positioning Modes of Operation Chapter 5 which is affected primarily by the speed of the differential data link. The MATCHEDPOS log contains the matched RTK solution and can be generated for each processed set of base station observations. The RTKDATA log provides additional information about the matched RTK solution and shows a verification flag in the "rtk info" field. It is recommended that you check this verification flag, especially in severe environments.
Chapter 5 Positioning Modes of Operation Table 19: RT-2 Degradation With Respect To Data Delay Data Delay (s) Distance (km) Accuracy (RMS) 0-2 1 +1 cm/s 2-7 1 +2 cm/s 7 - 30 1 +5 cm/s >60 1 single point or pseudorange differential positioning 2 1 Mode = Static or Kinematic 2 After 60 seconds reverts to pseudorange positioning (single point or differential depending on messages previously received from the base station).
Positioning Modes of Operation Chapter 5 RT-20 Performance As shown in Table 20, RT-20 Performance below, Figure 31 on Page 96 and Figure 32 on Page 96 the RT-20 system provides nominal 20 cm accuracy (RMS) after 15 minutes of continuous lock in static mode. After an additional period of continuous tracking (from 10 to 20 minutes), the system typically reaches steady state. The time to steady state is about 3 times longer in kinematic mode.
Chapter 5 Positioning Modes of Operation Figure 31: Typical RT-20 Convergence - Static Mode Figure 32: Typical RT-20 Convergence - Kinematic Mode 96 OEMV Family Installation and Operation User Manual Rev 5B
Positioning Modes of Operation Chapter 5 Performance Considerations When referring to the “performance” of RTK software, two factors are introduced: 1. Baseline length: the position estimate becomes less precise as the baseline length increases. Note that the baseline length is the distance between the phase centres of the two antennas. Identifying the exact position of your antenna’s phase centre is essential; this information is typically supplied by the antenna’s manufacturer or vendor.
Chapter 5 Positioning Modes of Operation ROVER TRACKING LOSS If less than 4 satellites are maintained, then the RTK filter can not produce a position. When this occurs, the BESTPOS and PSRPOS logs will be generated with differential (if pseudorange differential messages are transmitted with RTK messages) or single point pseudorange solutions if possible. DIFFERENTIAL LINK BREAKDOWN 98 1.
Chapter 6 PC Software and Firmware Visit the Firmware and Software Updates section of the NovAtel website, www.novatel.com, for the most recent versions of the PC software and receiver firmware. 6.1 CDU/Convert/DLVTool Installation The CD accompanying this manual contains the Windows applications CDU (Control and Display Unit), Convert and DLVTool. They are installed via a standard Install Shield set-up application.
Chapter 6 PC Software and Firmware CDU is a 32-bit Windows application. The application provides a graphical user interface (GUI) to allow you to set-up and monitor the operation of the NovAtel receiver by providing a series of windows whose functionality is explained in this section. A help file is included with CDU. To access the file, select Contents from the Help menu. See also Section 4.2.2, Communicating with the Receiver Using CDU starting on Page 58.
PC Software and Firmware Chapter 6 North. The colored rings indicate the lowest elevation cut-off angles at which satellites are tracked and can be changed or viewed via the button.
Chapter 6 PC Software and Firmware • The number of satellites used in the solution • The Solution Status • The receiver's date and time (GMT and local) Open this window by selecting Position Window from the View menu or its button in the Window Toolbar. Right-click in the Position window to that enables you to set the PC clock to the receiver's time, change the font used to display the position data or set the units through the Options dialog box.
PC Software and Firmware Chapter 6 point. The current position is shown with a red + marker. The buttons at the top of the window provide options for controlling the plan display: • Zoom in or out of the Plan window • View all configurations or center in on the active configuration • Select a grid or circular display • Show/Hide history • Delete all history (no undo) To open this window, select Plan Window from the View menu or select its button in the Window Toolbar.
Chapter 6 PC Software and Firmware This window automatically opens when CDU is first connected to a receiver. To bring the window to the front, select Console Window from the View menu or click its button in the Window Toolbar.
PC Software and Firmware 6.3 Chapter 6 Convert Convert is a 32-bit Windows application and is shown in Figure 33. Convert will accept GPS file formats and convert them to ASCII, Binary or Rinex format. The application also allows the user to screen out particular logs by selecting the desired logs from the list of available logs. This feature is useful for screening particular logs out of large data files in either ASCII or Binary formats. Figure 33: Convert Screen Examples 6.3.
Chapter 6 PC Software and Firmware The Convert4 utility can be used to produce RINEX files from NovAtel receiver data files. Although RINEX is intended to be a receiver-independent format, there are many optional records and fields. Please keep this in mind when combining NovAtel and non-NovAtel RINEX data. When converting to RINEX, two files are produced - a RINEX observation file and a RINEX navigation file. A third GLONASS file is produced if the data contains GLONASS observations.
PC Software and Firmware Chapter 6 Table 21: NovAtel Logs for Rinex Conversion NovAtel OEMV Family Log Recommended Trigger RANGEA/B, or RANGECMPA/B ontime 15 BESTPOSA/B, or PSRPOSA/B, or RTKPOSA/B, or MARKPOSA/B once IONUTCA/B onchanged RAWEPHEMA/B onchanged GLORAWEPHEMA/B onchanged VERSIONA/B a once SITEDEFA/B b once a.
Chapter 6 PC Software and Firmware The name of the output file is the same as the input file when converting to ASCII or binary formats. The file extension, however, is altered to indicate the format of the data: *.asc for ASCII *.bin for binary When converting to RINEX, the output files are named according to the RINEX Version 2.10 naming convention, see Section 6.3.1, Rinex Format on Page 105. The -batch arguments suppress the window display and convert the specified file automatically.
