! 14-1 product description ordering information typical applications features functional block diagram rf micro devices, inc. 7628 thorndike road greensboro, nc 27409, usa tel (336) 664 1233 fax (336) 664 0454 http://www.rfmd.com optimum technology matching? applied si bjt gaas mesfet gaas hbt si bi-cmos sige hbt si cmos ! 14 gps products gainp/hbt gan hemt sige bi-cmos gps antenna (30 db gain, 20 mhz bw) l1 bp filter lna gain digital asic filter adc temp. sensor rtc flash supervisor +2.5 v reg. osc. gps crystal (43 khz) rtc crystal (32 khz) low noise amplifier rf asic digital asic 1. +3.3 v 2. gnd 3. tx1 4. rx1 5. t-mark 6. v_antenna 7. +2.5 v battery 8. rx2 i/o connector RF8000 global positioning system receiver ? automotive navigation ? asset tracking ? fleet management ? telematics ? marine navigation the rfmd global positioning system (gps) receiver is a plug-n-play module designed for oem use. the 12-par- allel-channel gps rece iver works in a wide variety of end products including: marine navigation, telematics, auto- motive navigation, and asset tracking. the gps receiver processes signals from al l the visible gps satellites broadcasting rf navigation information. ?all-in-view? sat- ellite tracking produces high ly accurate, smoothed navi- gation data. the data is rela tively immune to the position jumps that occur when fewer satellites are monitored. designed to withstand harsh industrial environments, the gps receiver performs robust ly in situations where extreme vehicle movement or high signal blockage are concerns (such as dense urban areas). ? fast satellite time-to-first-fix (ttff) with a rapid acquisition module ? small footprint: 38mmx38mm ? supports 3d and 2d navigation modes ? automatic cold start acquisition process RF8000 global positioning system receiver rf8001 gps receiver with right angle connector dk8000 global positioning system receiver evaluation kit 14 rev a3 020603 package style: 38mmx38mm
14-2 RF8000 rev a3 020603 14 gps products absolute maximum ratings parameter rating unit supply current 150 ma rf input level -20 dbm operating ambient temperature -40 to +85 c storage temperature -40 to +85 c parameter specification unit condition min. typ. max. external power requirements 1 voltage 3.17 3.3 3.45 v dc operate mode 1.65 2.5 2.7 v dc battery backup mode power consumption 475 mw operate mode 320 mw 1 second updates 2 210 mw 10 second updates 2 33 mw 10 minute updates 2 6 a battery backup mode ripple peak-to-peak 100 mv operate mode n/a battery backup mode signal acquisition performance accuracy (95% all-in-view) 2 drms horizontal 5.8 m ver tical 9.7 m velocity 0.06 m/s dgps <1 m solution update rate 1 sec time mark 1 sec 1s100ns serial data output protocol binary, nmea-0183 version 2.30 or version 3.0. serial ports primary port 19,200 bps binary, no parity, 8 data bits, 1 stop bit auxiliary port 9600 bps rtcm sc-104, no parity, 8 data bits, 1 stop bit antenna requirements frequency 1575 mhz antenna gain 3 dbic at 90 elevation amplifier gain 30 db including cable loss amplifier filter noise bandwidth 20 mhz at the 3db points noise figure 2.5 db connector type mcx amplifier voltage, 3v dc to 5v dc 50 ma supplied by oem rf signal environment rf input frequency 1575.42 mhz l1 frequency band rf input power 31 db-hz sensitivity -113 dbm costas threshold 1 power must be within the specified li mits within 40ms after power turn-on. 2 results with power management software. (assumes a single 3.3v power supply and includes regulation losses.) expected release september 2002. caution! esd sensitive device. rf micro devices believes the furnished information is correct and accurate at the time of this printing. however, rf micro devices reserves the right to make changes to its products without notice. rf micro devices does not assume responsibility for the use of the described product(s).
14-3 RF8000 rev a3 020603 14 gps products parameter specification unit condition min. typ. max. environmental requirements cooling (operating/storage) free air convection temperature (operating/storage) -40 +85 c humidity 95 % relative humidity up to 95% non-condensing or a wet-bulb temperature of +35c, which- ever is less. altitude -1000 +60,000 ft maximum vehicle dynamic 515 m/s acquisition and navigation (meters per second) jerk 5 m/s 3 acceleration 4 g
14-4 RF8000 rev a3 020603 14 gps products package style module - 38mmx38mm dimensions in mm. 1 8 1.57 4.11 5.74 1 8 20.38 26.32 38.00 32.42 2.79 2.79 4.56 2.54 4 places 24.55 32.42 38.00 1 8 dimensions in mm. 20.38 26.32 38.00 24.55 32.42 2.79 2.79 2.54 4 places 4.11 1 8 1.57 6.22 1.93 32.42 38.00
14-5 RF8000 rev a3 020603 14 gps products theory of operation the rfmd gps receiver is a single-board, 12 parallel-channel engine designed for oem use. the gps receiver pro- cesses signals from the visibl e gps satellites broad casting rf navigation information. ?all-in-view? satellite tracking pro- duces highly accurate, smoothed navigation data. the data is relatively immune to the position jumps that occur when fewer satellites are monitored. designed to withstand harsh industrial environments, the gps receiver performs robustly in situation (such as dense urban areas) where extreme vehicle movement or high signal blockage are concerns. when fewer than four satellites are availa ble or when operating cond itions require, th e gps receiver su pports 2d navi- gation. to calculate a fix while in 2d navigation mode, the receiver uses either the last altitude determined while in 3d navigation mode, or data supplied by the user. satellite acquisition can be ob tained under most initialization situations, as long as the re ceiver can ?see? the satellites. rapid time to first fix (ttff) is a feat ure of the rapid se arch engine. the flexible satellite acquisition system takes advantage of all available information to provide rapid ttff, even without user init ialization. to minimize ttff when pri- mary power is removed from the receiver, a dc supply voltag e maintains the real time clock (rtc). this allows the gps receiver to use the prior position data and satellite information stored in the gps receiver?s flash memory. the receiver has two independent, asynchronous serial input/output ports. the receiver?s primary serial port outputs navigation data and accepts commands in the nmea-0183 or binary message formats. the receiver?s secondary serial port accepts differential gps (dgps) corrections in rtcm sc-104 format. see the ?message definitions? section for more information. receiver architecture the gps receiver chipset includes all the radio frequency (rf) direct sampling and amplification circuitry. these circuits present both the sign and magnitude of sampled data to the digital asic. the digital asic contains an integral micropro- cessor (powerpc r 401), the gps signal processing, sram, and the rtc. memory and other supporting components are needed to make a complete navigation system. receiver operation the receiver requires 3.3v dc primary input power. the receiver?s antenna must have visibilit y of the sky in order to acquire enough satellites to produce a navigation solu- tion. while this is usually not a problem outdoors, operation indoors or in a vehicle may require that the antenna be located with an unob structed view of the sky. if the satellites are blocked from the rece iver?s antenna, the receiver will take longer to acquire a position. if fewe r than four satellites are av ailable, the receiver may be able to determine a valid 2d position solution by using altitude aiding. signal acquisition modes the gps receiver supports the following four signal acquisit ion modes, depending on the av ailability of critical data. cold start in this mode, the receiver has valid almanac and frequency standard parameters available in memory. the receiver enters this mode on start-up when battery back-up power is not maintained. warm start in this mode, the receiver has the following valid data eith er available in memory or provided by the user at initialization: position, time, almanac, and frequency standard parameters. the receiver enters this mode on start-up when battery back-up power is maintained. hot start in this mode, the receiver has th e following valid data available in memory: position, velocity, time, ephemeris, almanac, and frequency standard parameters. the receiver enters this mode following a software reset or short power-off cycle when battery back-up power is maintained. reacquisition in this mode, the receiver has experienced a signal blockage for a short period of time (less than 10seconds) that was preceded by a period of continuous navigation.
14-6 RF8000 rev a3 020603 14 gps products table 1 (below) indicates the time to first fix (ttff) when opera ting in each of the si gnal acquisition modes. navigation modes the gps receiver supports three navigation modes: three-dimensional (3d), two-dimensional (2d) and differential gps (dgps). when four or more satellites are available with good geometry, the receiver enters the 3d navigation mode. when fewer than f our gps satellites are available, or when a fixed alti tude can be used to produc e an acceptable result, the gps receiver enters the 2d navigation mode. to calculate a fix in 2d navigation mode, the receiver uses either the last altitude determined in 3d navigation mode or data supplied by the user. in 2d navigation, navigational accuracy is primarily determined by the relationship of the fixed value of altitude to the tr ue altitude of the antenna. when four or more satellites are available with differential corrections, the receiver enters the dgps navigation mode. accuracy is a function of the entire gps system, including the geometry of the satellites at the time of measurement. individual gps receivers have very little influence over position accuracy. navigational accuracies are provided in table 2. power modes the gps receiver has the following three power modes. electrical requirements the host system supplies power as sp ecified in the parameter table. table 1. signal acquisition mode performance initial position tolerance (3 sigma) acquisition mode ttff 1,2 (seconds) position (km) velocity (m/sec.) time (minutes) maximum almanac age (weeks) maximum ephemeris age (hours) cold start 44 n/a 3 n/a 3 n/a 3 1 n/a 3 warm start 40 100 75 5 1 n/a 3 hot start 10 100 75 5 1 4 reacquisition 1 100 75 5 1 4 1 ty p i c a l va l u e s . 2 times given are valid at 25c with no signal blockage. 3 not available in real time to the receiver. table 2. navigational accuracy position (2drms, 95% all-in-view) horizontal vertical velocity dgps time 5.8m 9.7m 0.06 m/s <1m 100ns off mode the receiver is completely de-energized at all dc supplies, input signals and control signals. operate mode the receiver operates normally when an external dc supply is connected to the receiver?s pri- mary input terminal, v3_3p. battery back-up mode the receiver enters battery back-up mode when the primary input power voltage is removed, provided an external dc supply is connected to the rtc terminal, v2_5bu. if the receiver is powered up in this mode, it us es the current time from the rt c and critical satellite data stored in flash memory to achieve rapid ttff.
14-7 RF8000 rev a3 020603 14 gps products antenna power the gps receiver passes the voltage applied to the v_ant pin on the i/o connector to the center conductor of the rf connector. the voltage to v_ant can be either positive or negative and can range up to 15v dc . note: no form of current limiting is provided, and damage to the board may result if the rf center conductor is shorted to ground. antenna preamp, pass-through current must be limited outside the receiver. antenna sense circuit (optional feature) the optional antenna sense feature is useful for verifying the proper connection to the gps antenna. with this feature implemented, the gps receiver is capable of detecting antenna undercurrent and overcurrent conditions. the antenna sense status can be re quested using the ibit messag e and the results will be repo rted in the obit message. note: if the optional antenna sense circuit is used, the voltage to the v_ant pin on the gps receiver connector may either be +3.3v or 5v dc , depending on the specific antenna requirements. dc current is limited on the board to approx- imately 100ma. input/output signals signals are listed by pin number and described in table 3. all digital i/o signals are 2.5v dc cmos buffered signal levels, tolerant of 3.3v dc . table 3. input/output connections pin number signal name description 1 v3_3p main power input to the receiver. input power requirements are defined in table 3. 2gnd dc ground to the receiver. 3tx1 primary asynchronous full-duplex serial data port transmit (tx) line. binary and nmea mes- sage protocols are supported. the default settings are: message format binary baud 19200bps parity none data bits 8 stop bit 1 for additional information, see the gps receiver evaluation kit user manual. 4rx1 primary asynchronous full-duplex serial data port receive (rx) line. binary and nmea message protocols are supported. the default settings are: message format binary baud 19200bps parity none data bits 8 stop bit 1 for additional information, see the gps receiver evaluation kit user manual. 5tmark utc time-mark pulse, one pulse per second. the binary message otmp contains the utc time associated with the time-mark pulse. 6 v_ant provides a power connection to the center conductor of the rf connector. 7 v2_5bu provides a back-up power connection for the receiver?s real time clock (rtc). input power requirements are defined in table 3. 8rx2 auxiliary asynchronous full-duplex serial data port receive (rx) line. dgps rtcm sc-104 mes- sage protocol is supported. the default settings are: message format rtcm sc-104 baud 9600 parity none data bits 8 stop bit 1 for additional information, see the gps receiver evaluation kit user manual.
14-8 RF8000 rev a3 020603 14 gps products message definitions the following binary and nmea message definitions are provided in the rfmd gps receiver user manual (available with purchase of the gps receiver evaluation kit). contact rfmd customer service for more information. table 4. binary output messages binary message description default on onvd navigation solution data yes osat visible satellites on update ochs channel status yes odgs dgps status no odgc dgps configuration no onoc navigation operational configuration once at power-up/reset onvc navigation validity configuration once at power-up/reset onpc navigation platform configuration no ocsc cold start configuration once at power-up/reset oema elevation mask angle configuration once at power-up/reset odtm map datum select once at power-up/reset odtu user datum definition no otmp utc time mark pulse yes oald download almanac data no oepd download ephemeris data no outd download utc/iono data no oshm satellite health masking configuration no osid receiver software id once at power-up/reset obit built-in-test results (ack) no ofsh command flash upload (ack) no obid receiver boot code id (ack) once at power-up/reset table 5. binary input messages binary message description init navigation initialization idgc dgps configuration inoc navigation operational configuration invc navigation validity configuration inpc navigation platform configuration icsc cold start configuration iema elevation mask angle configuration idtm map datum select idtu user datum definition iald command almanac upload iepd command ephemeris upload iutd command utc/iono upload ishm satellite heal masking configuration irst command reset ifsh command flash upload ilog message log control iioc input/output port configuration impc message protocol configuration ibit command built-in-test
14-9 RF8000 rev a3 020603 14 gps products table 6. nmea output messages nmea message description default on sid software version once at power-up/reset gga gps fix data ye s gll geographic position: latitude/longitude no gsa gps dop and active satellites yes gsv gps satellites in view yes rmc recommended minimum specific gps/transit data yes vtg track made good and ground speed no bto built-in-test results (ack) no chs channel status data no table 7. nmea input messages nmea message description int receiver initialization log message log control ioc input/output port configuration mpc message protocol configuration rst command reset bti command built-in-test required table 8. rtcm sc-104 messages rtcm message description type 1 differential gps corrections type 2 delta differential gps corrections type 9 partial satellite set differential corrections
14-10 RF8000 rev a3 020603 14 gps products
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