Lassen SQ Reference Manual Download

Page: 61 / 196

C H A P T E R

Operation and Performance

In this chapter:

Introduction

GPS Satellite Message

Satellite Acquisition and Time to First Fix

Satellite Mask Settings

Standard Operating Modes

Position Accuracy

Coordinate Systems

Performance Characteristics

GPS Timing

System Architecture

Summary of Contents for SQ

Page 1: ...F Part Number 47838 00 Revision A June 2002 Lassen SQ GPS Receiver System Designer Reference Manual...

Page 2: ...ve others which vary from state jurisdiction to state jurisdiction Hardware Limited Warranty Trimble warrants that this Trimble hardware product the Product shall be free from defects in materials and...

Page 3: ...ATION PRODUCTION INSTALLATION OR DISTRIBUTION INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE TITLE AND NONINFRINGEMENT THE STATED EXPRESS W...

Page 4: ......

Page 5: ...6 TSIP 6 NMEA 6 Ordering Starter Kit Components 7 Starter Kit Interface Unit 8 Serial Port Interface 11 Pulse Per Second PPS 12 Power 13 Hardware Setup 15 Software Toolkit 17 2 Hardware Integration Ge...

Page 6: ...odes 38 Automatic TSIP Output Options and Defaults 38 Automatic TSIP Output Packets fixed rate 39 Packet Output Order 40 NMEA 0183 Protocol and Data Output Options 41 Custom Port Configuration 42 Timi...

Page 7: ...cture 65 A Trimble Standard Interface Protocol TSIP Interface Scope 68 Packet Structure 69 Automatic Output Packets 70 Customizing Receiver Operations 71 Automatic Position and Velocity Reports 71 Ini...

Page 8: ...Packet 0x2D Request Oscillator Offset 88 Command Packet 0x2E Set GPS Time 89 Command Packet 0x31 Accurate Initial Position 90 Command Packet 0x32 Accurate Initial Position 91 Command Packet 0x35 Set...

Page 9: ...122 Report Packet 0x82 Differential Position Fix Mode 122 Report Packet 0x83 Double Precision XYZ Fix and Bias 123 Report Packet 0x84 Double Precision LLA Fix and Bias 124 Packets 0x8E and 0x8F Superp...

Page 10: ...48 ZDA Time Date 149 Exception Behavior 150 Power up with No BBRAM 150 Power up with BBRAM 150 Interruption of GPS Signal 151 D Specifications and Mechanical Drawings Lassen SQ GPS Receiver Specificat...

Page 11: ...Contents Lassen SQ GPS Receiver xi General 163 Mechanical 164 Compact Unpackaged Antenna 166 Glossary...

Page 12: ...Contents xii Lassen SQ GPS Receiver...

Page 13: ...assumes that you are familiar with Microsoft Windows and know how to use a mouse select options from menus and dialogs make selections from lists and refer to online help Technical Assistance If you h...

Page 14: ...About this Manual xiv Lassen SQ GPS Receiver...

Page 15: ...C H A P T E R 1 Starter Kit 1 Product Overview Starter Kit Receiver Performance Interface Protocols Ordering Starter Kit Components Starter Kit Interface Unit Power Hardware Setup Software Toolkit...

Page 16: ...band chip The IO TS C33 integrates Trimble s IO digital signal processor with the Epson C33 RISC processor real time clock UART and 1Mbit memory Together with the colossus RF this implementation of Fi...

Page 17: ...r The motherboard also contains 3 6V lithium battery that provides back up power to the receiver Circuitry to convert the TTL output to RS 232 enabling the user to connect the RS 232 port in the Start...

Page 18: ...l flat head screw driver to pry the Lassen SQ GPS receiver module off the motherboard Warning Once the Lassen SQ GPS receiver module is removed from the motherboard the double sided tape looses some o...

Page 19: ...a CMOS TTL level pulse per second PPS output for timing applications or for use as a general purpose synchronization signal The Lassen SQ GPS receiver acquires a position fix with minimal delay after...

Page 20: ...tem designer maximum configuration control over the GPS receiver for optimum performance in any number of applications TSIP supports over 20 commands and their associated response packets for use in c...

Page 21: ...adapter power cable CD ROM containing software tools and the System Designer Reference Manual Table 1 1 provides ordering information for the Lassen SQ GPS module and the associated antennas and cabl...

Page 22: ...r an easy connection to a PC serial port using the serial interface cable provided in the Starter Kit The metal enclosure protects the module and the motherboard for testing outside of the laboratory...

Page 23: ...interface to a computer A 3 6V lithium backup battery enables quick hot starts The TTL level PPS is brought directly out to Pin 9 of the Port 2 DB9 connector on the front of the interface unit The St...

Page 24: ...four screws The eight pin I O header on the receiver module connects to a mating connector on a ribbon cable The ribbon cable is attached to a mating I O connector on the interface motherboard Figure...

Page 25: ...omputer or DTE Data Terminal Equipment device use a straight through cable To connect a Differential Radio DCE device to the receiver DCE Device use a cross over cable or null modem cable Table 1 2 Po...

Page 26: ...affect the pulse shape and rise time The PPS can drive a load up to 5mA without damaging the module The falling edge of the pulse should not be used The PPS is always on early PPS and is driven by the...

Page 27: ...environments The power cable is terminated at one end with a 3 pin plastic connector which mates with the power connector on the metal enclosure The un terminated end of the cable provides easy connec...

Page 28: ...a regulated 12 VDC compatible with the interface unit The AC DC power converter output cable is terminated with a 3 pin connector compatible with the power connector on the metal enclosure The AC pow...

Page 29: ...single port supports both the input output of TSIP messages and the output of NMEA messages Follow the steps below to setup the Starter Kit interface unit Figure 1 5 illustrates the setup Figure 1 5...

Page 30: ...na cable grasp the antenna mating MCX connector and pull from the MCX connector mounted on the interface unit 3 Using either the DC power cable or an AC DC power converter connect to the 3 pin power c...

Page 31: ...plug in the AC DC converter 3 Insert the CD in the computer s CD ROM drive 4 The SQ_Monitor program may be run directly off the CD or it may be copied onto your computer s hard drive To run the progr...

Page 32: ...for this field If a remains in the data field the GPS module may not be communicating with the computer Re check the interface cable connections and verify the serial port selection and settings If th...

Page 33: ...C H A P T E R 2 Hardware Integration 2 In this chapter General Description Connectors Power Requirements Serial Interface Pulse Per Second PPS Mounting GPS Antennas...

Page 34: ...locity and time PVT solutions for use in mobile battery powered applications such as cell phones pagers PDAs and digital cameras The Lassen SQ GPS module is packaged in a tiny form factor 26 mm x 26 m...

Page 35: ...Note See Appendix D for mechanical drawings and specifications Mating Connectors The customer must supply his own mating connector to the Lassen SQ GPS receiver 8 pin 2x4 connector There are two matin...

Page 36: ...for the symbol substitute the letter S for single end or D for double end for the XX symbol substitute the overall length in inches 1 8 inch with a 2 inch minimum Since the signals are CMOS TTL level...

Page 37: ...type Figure 2 3 Lassen SQ GPS Module with Connectors Possible cable manufactures include the following 1 48 mm diameter single shield cable CO 6F FH SB manufactured by Hitachi Cable Ltd UL1979 manufa...

Page 38: ...le to the module s RF connector For more information on the antennas see pag e30 2 2 3 Digital IO Power Connector Pinout The digital IO Power connector pinout information is listed in Table 2 1 Table...

Page 39: ...a command is sent to the receiver within this 2 1 second window the receiver will ignore the command The Lassen SQ GPS receiver will not respond to commands sent within the 2 1 second window and will...

Page 40: ...enter the cold start command TSIP Packet 0x1E to force a system reset and a cold start Cycle power and issue the cold start TSIP command immediately after switching the power back on Note 2 5V is the...

Page 41: ...e RX and TX signals on the J2 I O connector are driven directly by the UART on the Lassen SQ GPS receiver Interfacing these signals directly to a UART in your application circuitry provides direct ser...

Page 42: ...and rise time The PPS can drive a load up to 5mA without damaging the module The falling edge of the pulse should not be used The PPS is always on early PPS and is driven by the Real Time Clock RTC u...

Page 43: ...n the user s PCB When the cable strip I O connector scheme is used the connector side of the Lassen SQ GPS module will be faced up and the mounting tabs will be on the top of the module away from PCB...

Page 44: ...ed antenna is approximately the same size as the module itself and can be easily integrated into mobile applications This antenna is supplied with the Starter Kit see Figure 2 4 2 A Compact Unpackaged...

Page 45: ...Lassen SQ GPS Receiver 31 Hardware Integration 2 Figure 2 4 Ultra Compact Embedded GPS Antenna Figure 2 5 Compact Unpackaged GPS Antenna Figure 2 6 Compact Magnetic Mount GPS Antenna...

Page 46: ...2 Hardware Integration 32 Lassen SQ GPS Receiver...

Page 47: ...3 Software Interface 3 In this chapter Start up Communicating with the Lassen SQ GPS receiver Module Port Protocol and Data Output Options Custom Port Configuration When prompted select the factory d...

Page 48: ...ered up it is searching for satellites from a cold start no almanac While the receiver will begin to compute position solutions within the first two minutes the receiver must continuously track satell...

Page 49: ...pplications to facilitate communication with the receiver via the Trimble Standard Interface Protocol TSIP This CD also includes sample C source code and reusable routines to aid in developing applica...

Page 50: ...the TSIP protocol in text format use the TSIPCHAT or the SQ_Monitor program see the CD ROM provided in the Starter Kit The serial port driver in the TSIPCHAT Tool Kit matches the Lassen SQ GPS receive...

Page 51: ...the DOS or Windows operating systems Responses are displayed on the computer monitor in text format SQ_Monitor a Windows based GUI provides a versatile graphical interface for monitoring TSIP data Thi...

Page 52: ...automatic output packets is configured using packets 0x35 0x70 and 0x8E 20 see Appendi xA for packet details Packet settings are stored in BBRAM They can also be saved in non volatile memory Flash us...

Page 53: ...ic Filter enabled Position Velocity static Filter enabled Altitude Filter enabled Default 0x8E 20 setting byte 1 1 0x8F 20 output is included in the super packet for automatic output IF packet 0x35 se...

Page 54: ...ut Order After power up or a software reset packet 0x1E seven start up packets are sent only once by the receiver in this order 45 46 4B 4A 56 41 82 Before position fixes are available the 1 second an...

Page 55: ...ntence In the Lassen SQ GPS receiver NMEA is an output only protocol The NMEA protocol is described in detail in Appendix C The receiver is shipped from the factory with the TSIP protocol configured o...

Page 56: ...tile memory Following are step by step instructions for using TSIPCHAT to customize Lassen SQ GPS receiver port configuration Customizing the Configuration 1 Insert the CD in the CD ROM drive of your...

Page 57: ...e returned to the default configuration 2 To save the configuration to Flash Enter to access the command list page for the 0x8E command packet Enter s to send the 0x8E 26 command packet Communication...

Page 58: ...sh Memory Command Packet 0x8E 26 TSIP Command ID TSIPCHAT Keystroke Description TSIP Response ID 0x35 O TSIP input output formatting Superpacket output on off Position format LLA and or ECEF Precision...

Page 59: ...sk DOP mask PDOP switch DGPS correction age 0xBB 0xBC U Serial port configuration Protocol input output Baud data bits parity stop bits 0xBC 0x8E 20 g Fixed point superfix control default on 0x8F 20 T...

Page 60: ...of April 2002 the GPS UTC offset was 13 seconds The offset increases by 1 second approximately every 18 months System designers should plan to read the offset value as a part of the timing interface t...

Page 61: ...4 In this chapter Introduction GPS Satellite Message Satellite Acquisition and Time to First Fix Satellite Mask Settings Standard Operating Modes Position Accuracy Coordinate Systems Performance Chara...

Page 62: ...to the detailed discussion of the satellite acquisition and tracking process please review the GPS satellite message description on the next page The Lassen SQ GPS receiver satellite acquisition and t...

Page 63: ...The ephemeris is repeated every 30 seconds The system almanac contains information about each of the satellites in the constellation ionospheric data and special system messages The GPS system almana...

Page 64: ...cted satellites is acquired after a pre determined period of time time out the receiver will select a new search set of eight satellites and will repeat the process until the first satellite is acquir...

Page 65: ...SQ GPS receiver identifies the satellites which are expected to be in view given the system almanac the initial position and the approximate time The receiver calculates the elevation and expected Dop...

Page 66: ...re invalid The stored information is flushed from memory if the cold start search proves effective and the warm search fails 4 3 5 System Reset The Lassen SQ GPS receiver can be reset with software co...

Page 67: ...reset Issuing the 0x1E command with a value of 0x4B Cycling power without back up power applied Using this method power must be removed for at least 3 minutes to ensure any residual memory storage is...

Page 68: ...asks observed by the Lassen SQ GPS receiver are listed in Table 1 These masks serve as the screening criteria for satellites used in fix computations and ensure that position solutions meet a minimum...

Page 69: ...sually necessary to use satellites below a 5 elevation to improve GPS coverage time In some applications like urban environments a higher mask may be warranted to minimize the frequency of constellati...

Page 70: ...l contribute to a lower position accuracy For most applications a DOP mask of 12 offers a satisfactory trade off between accuracy and GPS coverage time With world wide GPS coverage now available the D...

Page 71: ...the Lassen SQ GPS receiver will only generate 2 dimensional 2D position solutions latitude and longitude only regardless of the number of visible satellites If the altitude is not entered the receiver...

Page 72: ...h to 2 dimensional 2D mode and will use the last calculated altitude if available or the default altitude in the position solution In 2D 3D Automatic mode the PDOP switch is active 4 6 Position Accura...

Page 73: ...dinate systems The output format is chosen by TSIP command 0x35 The output formats include the following LLA position Latitude longitude altitude LLA according to the WGS 84 ellipsoid Altitude can be...

Page 74: ...e world UTC time replaced GMT Greenwitch Mean Time as the world standard in 1986 GPS time is steered relative to Universal Coordinated Time UTC GPS does not recognize leap seconds resulting in a situa...

Page 75: ...isted below These operating limits assume that the GPS module is correctly embedded and that the overall system is designed to operate under the same dynamic conditions Note The Lassen SQ GPS Receiver...

Page 76: ...ration the receiver continues to search for the lost signal at the satellite s last known Doppler frequency If the signal is available again within 15 seconds the receiver will normally re establish t...

Page 77: ...ated by its internal clock which is constantly corrected using the GPS clocks This timing pulse is synchronized to UTC within 95 ns In addition to serving as a highly accurate stand alone time source...

Page 78: ...and I O connector The rising edge of the PPS pulse is synchronized with respect to UTC The timing accuracy is 95 nanoseconds when valid position fixes are being reported The rising edge of the pulse...

Page 79: ...nals through the antenna feed line connector and passes them to the RF down converter A highly stable crystal reference oscillator operating at 12 504 MHz is used by the down converter to produce the...

Page 80: ...Filter PLL XTAL1 I LPF RF Q LPF Baseband Filter POWMON VSTBY XCLK Linear Regulator 12 504MHz TCXO RF Connector Active L1 Antenna Antenna Protect and Monitor I_OUT Q_OUT SAMP_IN CLK_out 3 126MHz Sampli...

Page 81: ...f a specific application This appendix provides the information needed to make judicious use of the powerful features TSIP has to offer to greatly enhance overall system performance and to reduce the...

Page 82: ...SIP protocol is based on the transmission of packets of information between the user equipment and the unit Each packet includes an identification code 1 byte representing 2 hexadecimal digits that id...

Page 83: ...hat a simple DLE ETX sequence does not necessarily signify the end of the packet as these can be bytes in the middle of a data string The end of a packet is ETX preceded by an odd number of DLE bytes...

Page 84: ...d below depending on the selected I O options While there are other packets automatically output the following packets provide the information most commonly used No input packets are required Table A...

Page 85: ...by Packet 35 Setting the control bits as indicated in the table below allows you to control which position and velocity packets are output Table A 2 Packet 35 Automatic Position and Velocity Reports...

Page 86: ...th battery power when main power is off you can still warm start the receiver by sending the following commands after the receiver has completed its internal initialization and has sent Packet 82 Tabl...

Page 87: ...complete and the receiver is ready to accept commands A 8 Timing Packets If you are using the Lassen SQ GPS receiver as a timing system you may need to implement the following TSIP control commands Ta...

Page 88: ...in the Lassen SQ GPS receiver are backward compatible with those used in Lassen SK II GPS receiver For information regarding compatibility with other Trimble receivers contact the Trimble Technical As...

Page 89: ...ecision LLA 0x37 auto 0x84 double precision XYZ 0x37 auto 0x83 ENU velocity 0x37 auto 0x56 XYZ velocity 0x37 auto 0x43 Satellite and tracking information query receiver state health 0x26 0x46 0x4B que...

Page 90: ...full reset clear battery backup and or non volatile settings 0x1E soft reset 0x25 set GPS time 0x2E 0x4E set exact LLA 0x32 set approx XYZ 0x23 set approx LLA 0x2B set exact XYZ 0x31 Table A 8 User S...

Page 91: ...an ECEF 0x32 accurate initial position 0x35 I O options 0x55 0x37 status and values of last position and velocity 0x57 0x38 load or request satellite system data 0x58 0x3C tracking status 0x5C see Not...

Page 92: ...46 health of Receiver 0x26 auto power up 0x47 signal level for all satellites 0x27 0x4A single precision LLA position 0x37 auto 0x4B machine code status 0x26 auto power up 0x4D oscillator offset 0x2D...

Page 93: ...obscuration and whether accuracy or fix density is important In this table NA indicates that the operating parameter is not applicable DC don t care indicates that the user may choose the operating pa...

Page 94: ...an the DOP mask This mode supplies fairly continuous position fixes even when there is frequent obscuration This mode is preferable for most land or air applications where altitude changes are occurri...

Page 95: ...tines are optimized for vehicle type environments In SEA mode the search and re acquisition routines assume a low acceleration environment and reverts to user entered altitude in 2 D auto In AIR mode...

Page 96: ...AMU High accuracy users may use a slightly higher mask of 6 0 8 0 since weaker measurements may be slightly noisier and are often caused by reflected signals which provide erroneous ranges One should...

Page 97: ...ich the receiver stops attempting a 3 D solution and tries for a 2 D solution when in automatic 2 D 3 D mode The switch level has no effect in either manual mode Raising the DOP mask will generally in...

Page 98: ...executing the Factory Reset command In normal use this packet should not be sent Warning It is very helpful to keep a fresh copy of the current almanac which is stored in the file GPSALM DAT collected...

Page 99: ...Position XYZ Cartesian ECEF This packet provides the GPS receiver with an approximate initial position in XYZ coordinates This packet is useful if the user has moved more than about 1 000 miles since...

Page 100: ...he GPS receiver sends Packet 0x45 only on power up and reset or on request thus if Packet 0x45 appears unrequested then either the GPS receiver power was cycled or the GPS receiver was reset A 15 7 Co...

Page 101: ...t sets or requests the altitude parameters used for the Manual 2 D mode Reference Altitude and Altitude Flag Packet 0x4A 9 byte format is returned Note With no data bytes this packet requests the curr...

Page 102: ...ed for initialization This packet is ignored if the receiver is already calculating positions The data format is shown in the table below Note To initialize with ECEF position use Command Packet 0x23...

Page 103: ...1980 The seconds count begins at the midnight which begins each Sunday morning This packet is usually not required when the battery back up voltage is applied as the internal clock keeps time to suffi...

Page 104: ...he position provided in this packet to be accurate This packet is used for satellite acquisition aiding in systems where another source of position is available For acquisition aiding the position pro...

Page 105: ...iver assumes the position provided in this packet to be accurate This packet is used for satellite acquisition aiding in systems where another source of position is available For acquisition aiding th...

Page 106: ...ir default settings and the byte values for all possible configurations are shown below The Set Request I O options are stored in battery backed memory To store them in non volatile RAM Flash use the...

Page 107: ...utput Bit 0 1 HAE Note 1 MSL geoid 0x4A 0x84 0x8F 17 0x8F 18 3 ALT input Bit 0 1 HAE Note 1 MSL geoid 0x2A 4 Precision of position output Bit 0 1 Send single precision packet Send double precision pac...

Page 108: ...output of 0x5A messages is supported in the Lassen SQ GPS receiver for backwards compatibility with older TSIP applications Auxiliary Pseudo Range Measurements 3 0 Raw measuring Bit 0 1 Raw measuremen...

Page 109: ...te System Data This packet requests current satellite data almanac ephemeris etc or permits loading initialization data from an external source for example by extracting initialization data from an op...

Page 110: ...e retrieved and stored for later download The ephemeris data cannot be loaded into the receiver Table A 20 Command Packet 0x38 Data Formats Byte Item Type Value Definition 0 Operation UINT8 1 2 Reques...

Page 111: ...shown below Note UTC time lags behind GPS time by an integer number of seconds UTC GPS time GPS UTC offset Warning GPS week number runs from 0 to 1023 and then cycles back to week 0 week 0 began Janu...

Page 112: ...tion in Packet 0x41 and the Packet 0x46 status code Note Before using the GPS time from Packet 0x41 verify that the Packet 0x46 status code is 00 Doing position fixes This will ensure the most accurat...

Page 113: ...I O Precision of Position Output byte 0 bit 4 Packet 0x35 is set to single precision then the GPS receiver sends this packet each time a fix is computed The data format is shown below The time of fix...

Page 114: ...ket 0x35 then the GPS receiver sends this packet each time a fix is computed The data format is shown below The time of fix is in GPS time or UTC as selected by the I O timing option byte 2 bit 0 Pack...

Page 115: ...this packet after power on and in response to Packet 0x1F The first 5 bytes refer to the Navigation Processor and the second 5 bytes refer to the Signal Processor Table A 26 Report Packet 0x45 Data Fo...

Page 116: ...des in Byte 1 of Packet 0x46 are encoded into individual bits within the byte The bit positions are their meanings are shown below Note After status is detected its bit remains set until the receiver...

Page 117: ...may be sent indicated by the count field Signal level is normally positive If it is zero then that satellite has not yet been acquired If it is negative then that satellite is not currently in lock Th...

Page 118: ...d depending on which I O LLA altitude option is selected The time of fix is in GPS time or UTC depending on which I O timing option is selected This packet also is sent at start up with a negative tim...

Page 119: ...de used for manual 2 D positions if the altitude flag is set Altitude is in units of HAE WGS 84 or MSL depending on the selected I O options set for positioning with Command Packet 35 Altitude Flag A...

Page 120: ...e equipment is connected Then the interpretation and use of packets can be adjusted accordingly The status codes are encoded into individual bits within the bytes The bit positions and their meanings...

Page 121: ...29 Report Packet 0x4E Response to Set GPS Time Indicates whether the receiver accepted the time given in a Set GPS time packet the receiver sends this packet in response to Packet 0x2E This packet con...

Page 122: ...0x35 Data Descriptions Byte Bit Item Type Value Definition Position 0 0 XYZ ECEF Bit 0 1 XYZ ECEF output off XYZ ECEF output on 0 1 LLA Output Bit 0 1 LLA output off LLA output on 0 2 LLA ALT Output...

Page 123: ...assen SQ GPS receiver for backwards compatibility with older TSIP applications Timing 2 0 Time Type Bit 0 1 GPS time UTC 2 1 7 reserved Auxiliary Range Measurements 3 0 Raw measuring Bit 0 1 Raw measu...

Page 124: ...conditions Each time that a fix is computed In response to Packet 0x37 last known fix The data format is shown below The time of fix is in GPS or UTC time as selected by the I O timing option Table A...

Page 125: ...of the previous position fix The receiver sends this packet among others in response to Packet 0x37 The data format is shown below Table A 36 Report Packet 0x57 Data Formats Byte Item Type Units Byte...

Page 126: ...referred To get ionosphere or ephemeris this report must be used Note Ephemeris cannot be loaded into Lassen SQ GPS receiver Table A 37 Report Packet 0x58 Data Formats Byte Item Type Value Definition...

Page 127: ...45 a_f1 Single Sec 20 3 3 5 1 2 46 49 Axis Single Sec 20 3 3 5 1 2 50 53 n Single Sec 20 3 3 5 1 2 54 57 OMEGA_n Single Sec 20 3 3 5 1 2 58 61 ODOT_n Single Sec 20 3 3 5 1 2 62 65 t_zc Single Sec 20 3...

Page 128: ...e Sec 20 3 3 5 1 9 40 43 beta_3 Single Sec 20 3 3 5 1 9 Table A 41 Byte Item Type Definition IDC GPS 200 4 16 not used 17 24 A_0 Double Sec 20 3 3 5 1 8 25 28 A_1 Single Sec 20 3 3 5 1 8 29 30 delta_t...

Page 129: ...3 36 a_f0 Single Sec 20 3 3 3 Table 20 I 37 40 SVacc Single Sec 20 3 3 3 Table 20 I 41 IODE UINT8 Sec 20 3 3 4 42 fit_interval UINT8 Sec 20 3 3 4 43 46 C_rs Single Sec 20 3 3 4 47 50 delta_n Single Se...

Page 130: ...mega Double Sec 20 3 3 4 123 126 OMEGADOT Single Sec 20 3 3 4 127 130 IDOT Single Sec 20 3 3 4 131 138 Axis Double sqrt_A 2 139 146 n Double derived from delta_n 147 154 r1me2 Double sqrt 1 0 e2 155 1...

Page 131: ...measurement taken from this satellite 12 15 Elevation Singles radians Approximate elevation of this satellite above the horizon Updated about every 15 sec s Used for searching and computing measureme...

Page 132: ...le length equal to 16 nSVs where nSVs is the number of satellites used in the solution The GPS receiver sends this packet in response to Packet 0x24 The data format is shown below Note The Lassen SQ G...

Page 133: ...is no lag due to vehicle dynamics There may be a small increase in accuracy however A feature of the PV filter is the Static Filter which engages when the receiver is moving very slowly This feature i...

Page 134: ...a response to Command Packet 0x70 as either a query or a set It contains four bytes as shown in Table A 46 Table A 45 Command Packet 70 Data Formats Byte Item Type Value Definition 0 Position Velocit...

Page 135: ...val and message mask While fixes are being generated the output order is ZDA GGA GLL VTG GSA GSV RMC Table A 46 Command Packet 0x7A and Report Packet 0x7B Data Formats Byte Bit Item Type Value Definit...

Page 136: ...current automatic mode 2 or 3 and does not do position solutions Valid modes are Mode 0 Differential off Manual GPS The receiver does position solutions without differential corrections even if the d...

Page 137: ...ecision of Position option is set to Double see Packet 0x35 the receiver sends this packet each time a fix is computed The data format is shown below The time of fix is in GPS time or UTC as selected...

Page 138: ...or UTC as selected by the I O timing option Warning When converting from radians to degrees significant and readily visible errors will be introduced by use of an insufficiently precise approximation...

Page 139: ...mand Packet 0xBB Query Mode Data Format Byte Item Type Value Definition Default 0 Subcode UINT8 0x00 Query mode Table A 50 Command and Report Packet 0xBB Field Descriptions Byte Item Type Value Defini...

Page 140: ...xBC and provides query field descriptions The BC command settings are retained in battery backed RAM 17 20 DOP Switch Single 0 2 100 Selects 2D 3D mode 5 0 21 DGPS Age Limit UINT8 2 90 seconds Maximum...

Page 141: ...T8 2 3 7 bits 8 bits 4 Parity UINT8 0 1 2 None Odd Even 5 Stop Bits UINT8 0 1 1 bit 2 bits 6 Flow Control UINT8 0 0 none 7 0 reserved Bit 0 1 TSIP input Bit 0 1 off on 2 reserved Bit 0 3 reserved Bit...

Page 142: ...Fix with Extra Information This packet requests Packet 0x8F 20 or marks it for automatic output If only the first byte 20 is sent an 0x8F 20 report containing the last available fix will be sent imme...

Page 143: ...eport Packet 0x8F 20 Data Formats Byte Bit Item Type Value Definition 0 Sub packet id UINT8 Id for this sub packet always 0x20 1 KeyByte UINT8 Reserved for Trimble DGPS Post processing 2 3 east veloci...

Page 144: ...UTC Offset UINT8 Number of leap seconds between UTC time and GPS time 30 31 Week INT16 GPS time of fix weeks 32 0 5 PRN 1 UINT8 1 32 PRN of first satellite 6 7 reserved 33 IODE 1 UINT8 IODE of first...

Page 145: ...IODE of fifth satellite 42 0 5 PRN 6 UINT8 1 32 PRN of sixth satellite 6 7 reserved 43 IODE 6 UINT8 IODE of sixth satellite 44 0 5 PRN 7 UINT8 1 32 PRN of seventh satellite 6 7 reserved 45 IODE 7 UINT...

Page 146: ...lues have been saved See Chapter 3 Software Interface for information on the settings that can be saved to non volatile memory A 16 4 Report Packet 0x8F 26 Non Volatile Memory Status This report will...

Page 147: ...ware so the source code in ANSI C is included for many of these programs The GPS Tool Kit program disk includes the following programs 32 bit Windows Applications SQ_Monitor is a 32 bit windows applic...

Page 148: ...plication which interprets a binary TSIP data stream such as logged by TSIPCHAT or SQ_Monitor and prints it to a file Source code is provided For further information on the above programs see the READ...

Page 149: ...itor displays delta position which is the difference between the current position and the initial position The initial position can be reset at anytime by selecting Reset Initial Position see B 1 4 Fi...

Page 150: ...B TSIP Tool kit User s Guide 136 Lassen SQ GPS Receiver...

Page 151: ...se in applications other than marine electronics The latest release of NMEA 0183 is Version 3 0 July 1 2000 Trimble Navigation supports both version 2 1 and version 3 0 The primary change in release 3...

Page 152: ...1 The NMEA 0183 Communication Interface NMEA 0183 allows a single source talker to transmit serial data over a single twisted wire pair to one or more receivers listeners The table below lists the st...

Page 153: ...the navigation information The GP identification signifies a GPS source MSG The message identification is a three letter mnemonic which describes the message content and the number and order of the d...

Page 154: ...luded for degrees and minutes to maintain fixed length The decimal point and associated decimal fraction are optional if full resolution is not required Longitude yyyyy yyy Fixed Variable length field...

Page 155: ...indicated in this standard by the presence of one or more valid characters Excluded from the list of allowable characters are the following that are used to indicated field types within this standard...

Page 156: ...es are permanently replaced until the receiver is returned to the factory default settings Note The user can configure a custom mix of the messages listed in Table C 3 See Chapter 3 and TSIP command p...

Page 157: ...1 UTC of Position 2 3 Latitude N North or S South 4 5 Longitude E East or W West 6 GPS Quality Indicator 0 No GPS 1 GPS 2 DGPS 7 Number of Satellites in Use 8 Horizontal Dilution of Precision HDOP 9 1...

Page 158: ...tatus GPGLL llll lll a yyyyy yyy a hhmmss ss A i hh CR LF Table C 5 GLL Geographic Position Latitude Longitude Message Parameters Field Description 1 2 Latitude N North or S South 3 4 Longitude E East...

Page 159: ...ameters Field Description 1 Mode M Manual A Automatic In manual mode the receiver is forced to operate in either 2D or 3D mode In automatic mode the receiver is allowed to switch between 2D and 3D mod...

Page 160: ...pectively GPGSV x x xx xx xx xxx xx xx xx xxx xx xx xx xxx xx xx xx xxx xx hh CR LF Table C 7 GSV GPS Satellites in View Message Parameters Field Description 1 Total number of GSV messages 2 Message n...

Page 161: ...ily unavailable GPRMC hhmmss ss A llll ll a yyyyy yy a x x x x xxxxxx x x a i hh CR LF Table C 8 RMC Recommended Minimum Specific GPS Transit Data Message Parameters Field Description 1 UTC of Positio...

Page 162: ...hh CR LF Table C 9 VTG Track Made Good and Ground Speed Message Parameters Field Description 1 Track made good in degrees true 2 Track made good in degrees magnetic 3 4 Speed over the ground SOG in k...

Page 163: ...ly identify the local time zone offsets Warning If UTC offset is not available time output will be in GPS time until the UTC offset value is collected from the GPS satellites When the offset becomes a...

Page 164: ...y If the output message list and output rate has been customized using TSIP command packet 0x7A and stored in Flash memory then at power up the receiver will output the messages according to the custo...

Page 165: ...n of GPS Signal If the GPS signal is interrupted temporarily the NMEA will continue to be output according to the user specified message list and output rate Position and velocity fields will be blank...

Page 166: ...C NMEA 0183 152 Lassen SQ GPS Receiver...

Page 167: ...is designed for embedded industrial computing or control mobile computing or data collection precision timing and vehicle tracking applications This appendix includes the system specifications and mec...

Page 168: ...c PPS 95 nanoseconds Acquisition Reacquisition 2 sec 90 Hot Start 14 sec 50 18 sec 90 Warm Start 38 sec 50 45 sec 90 Cold Start 90 sec 50 170 sec 90 Dynamics Acceleration 4g 39 2 m sec2 Motional jerk...

Page 169: ...3 mW 3 3V Backup Power 2 5 VDC to 3 6 VDC Ripple Noise Max 60 mV peak to peak from 1 Hz to 1 MHz D 1 4 Environmental Operating Temp 40 C to 85 C Storage Temp 55 C to 105 C Vibration 0 008 g2 Hz 5 Hz...

Page 170: ...onnector Compact Unpackaged Antenna 3 V active micropatch unpackaged antenna Cable length 11cm Dim 34 6 mm W x 29 mm L x 9 mm H 1 362 x 1 141 x 0 354 Connector MCX mates with optional RF transition ca...

Page 171: ...Lassen SQ GPS Receiver 157 Specifications and Mechanical Drawings D...

Page 172: ...1 8 1 6 1 4 1 2 9 7 5 3 1A1 1A2 1A3 1A4 2A1 2A2 2A3 2A4 1 G 2 G 1 Y 1 1 Y 2 1 Y 3 1 Y 4 2 Y 1 2 Y 2 2 Y 3 2 Y 4 R 4 1 1 K P A R T _ N O D 1 2 6 8V BiDirect Trans P A R T _ N O 2 1 J2 N O _ L O A D P A...

Page 173: ...X 60mm square ground plane Polarization RHCP Axial Ratio 90 4 0dB max 10 6 0dB max mounted on the 60mm X 60mm square ground plane D 2 2 LNA Frequency range 1 575 42 1 023MHz Gain 24 3 dB 25 C 5 C 24 4...

Page 174: ...utput Impedance 50 VSWR 2 0 max MTBF 5 13E 6Hr D 2 4 Storage Conditions Store in room condition as listed below Temperature 20 C to 45 C humidity 80 max Data Gain at 3 0V 0 3V f 1575MHz and power cons...

Page 175: ...Lassen SQ GPS Receiver 161 Specifications and Mechanical Drawings D...

Page 176: ...he 65mm X 65mm square ground plane Polarization RHCP Axial Ratio 90 4 0dB max 10 6 0dB max mounted on the 65mm X 65mm square ground plane D 3 2 LNA Frequency range 1 575 42 1 023MHz Gain 28 3 dB 40 C...

Page 177: ...Output Impedance 50 VSWR 2 0MAX ESD Antenna surface 15KV Connector pin 8KV MTBF 5 13E 6Hr D 3 4 Storage Conditions Temperature 20 C to 45 C humidity 80 max consumption at room temperature D 3 5 Gener...

Page 178: ...sweep time 15 min 3 axis Withstand min speed of 180Km h Cable pulling force5kgf min Visible or electrical damage must not appear when applying up to 5kgf pulling force between cable and antenna as we...

Page 179: ...Lassen SQ GPS Receiver 165 Specifications and Mechanical Drawings D...

Page 180: ...6 Lassen SQ GPS Receiver D 4 Compact Unpackaged Antenna The specifications for this antenna are identical to that of the Compact Magnetic Mount Antenna described earlier in this Appendix see page 162...

Page 181: ...Lassen SQ GPS Receiver 167 Specifications and Mechanical Drawings D...

Page 182: ...D Specifications and Mechanical Drawings 168 Lassen SQ GPS Receiver...

Page 183: ...altitude 2 D Two Dimensional A 2 D position is defined as latitude longitude and altitude 3 D GPS mode A procedure of determining a 3 D position using signals received from the best or only four avail...

Page 184: ...clockwise from true North bandwidth The range of frequencies occupied by a signal Also the information carrying capability of a communication channel or line baud A measure of the speed of data transm...

Page 185: ...of the earth Many local datums model the earth for a small region e g Tokyo datum Alaska NAD 27 North America Others WGS 84 for example model the whole earth DCE Data Communications Equipment The equ...

Page 186: ...positioning Determination of relative coordinates of two or more receivers which are simultaneously tracking the same satellites Static differential GPS involves determining baseline vectors between...

Page 187: ...gle is used to prevent the GPS receiver from computing position solutions using satellites which are likely to be obscured by buildings or mountains ellipsoid In geodesy unless otherwise specified a m...

Page 188: ...lipsoid and a point on the topographic surface established as the origin of datum This relationship can be defined by six quantities generally but not necessarily the geodetic latitude longitude and t...

Page 189: ...combination of a GPS antenna and a GPS processor GPS time The length of the second is fixed and is determined by primary atomic frequency standards Leap seconds are not used as they are in UTC Therefo...

Page 190: ...a function of time masks See satellite masks maximum PDOP A measure of the maximum Position Dilution of Precision PDOP that is acceptable in order for the GPS processor to determine a location soluti...

Page 191: ...of the range from the GPS antenna to a GPS satellite Pseudo range is obtained by multiplying the speed of light by the apparent transit time of the signal from the GPS satellite Pseudo range differs...

Page 192: ...k A satellite is said to rise when its elevation angle exceeds the mask and set when the elevation drops below the mask ROM Read Only Memory RS 232 A communication standard for digital data Specifies...

Page 193: ...o A measure of the relative power levels of a communication signal and noise on a data line SNR is expressed in decibels dB SNR Signal to Noise Ratio spread spectrum The received GPS signal is a wide...

Page 194: ...nced Navigation Sensor Also refers to a Trimble specified interface protocol for digital packet communication to from the GPS receiver Data output includes time tagged position and velocity satellite...

Page 195: ...e apparent clock and ephemeris prediction accuracies to the ranging accuracies obtainable with a specific satellite based on historical data UTC Universal Time Coordinated Uniform atomic time system s...

Page 196: ...Glossary 182 Lassen SQ GPS Receiver...

Search results

Summary of Contents for SQ

Reviews:

Related manuals for SQ

Brands by name

Popular brands

Lassen SQ, Reference Manual

Search results

Summary of Contents for SQ

Reviews:

Related manuals for SQ

Brands by name

Popular brands