ONCORE TECHNICAL APPLICATION NOTE

It’s Not Where You Are, It’s Where You’re Going.TM
ONCORE ENGINEERING NOTE
M12 Oncore
1.
Product Specifications
2.
Basic Description
3.
Mechanical
4.
Environmental
5.
Electrical
6.
RF Characteristics of Receiver
7.
RF Requirements for Antenna
8.
Performance
9.
Features
10. Serial I/O Messages
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 1 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
1.
Preliminary M12 Oncore Product Specifications
General
Characteristics
Receiver Architecture
• 12 parallel channel
• L1 1575.42 MHz
• C/A code (1.023 MHz chip rate)
• Code plus carrier tracking (carrier aided tracking)
Performance
Characteristics
Tracking Capability
• 12 simultaneous satellites
Dynamics
• Velocity: 515 m/s (1000 knots); > 515 m/s at altitudes < 18,000 m
• Acceleration: 4 g
3
• Jerk: 5 m/s
• Vibration: 7.7G per Military Standard 810E
Acquisition Time
• <15 sec. typical TTFF - Hot (current almanac, position, time, ephemeris)
(Time To First Fix, TTFF)
• <40 sec. typical TTFF - Warm (current almanac, position and time)
• <60 sec. typical TTFF - Cold (No stored information)
(Tested at -30 to +85°C)
• <1.0 sec. internal reacquisition (typical)
Positioning Accuracy
• 100 meters 2dRMS with SA as per DoD specification
• Less than 25 meters, SEP without SA
Timing Accuracy (1PPS)
• < 500 ns with SA on
Antenna
• Active micro strip patch Antenna Module
• Powered by Receiver Module (15 mA @ 3 Vdc) (optional 5 Vdc available)
Datum
• WGS-84
• One user definable datum
Serial
Communication
Output Messages
• Latitude, longitude, height, velocity, heading, time
• Motorola binary protocol at 9600 baud
• NMEA 0183 at 4800 baud (GGA, GLL, GSA, GSV, RMC, VTG, ZDA)
• Software selectable output rate (continuous or poll)
• TTL interface (0 to 3 V)
• Second COM port for RTCM input
Electrical
Characteristics
Physical
Characteristics
Power Requirements
• 2.75 to 3.2 Vdc; 50 mVp-p ripple (max.)
"Keep-Alive" BATT Power
• External 2.75 Vdc to 3.2 Vdc, 5µA (typical @2.7Vdc)
Power Consumption
• <0.225 W @ 3 V without antenna
Dimensions
• 40.0 x 60.0 x 10.0 mm
Weight
• Receiver 25 g (0.9 oz.)
[1.57 x 2.36 x 0.39 in.]
• Active Antenna Module < 40 g
Connectors
• Power/Data: 10 pin (2x5) unshrouded header on 0.050 in. centers
(Available in right angle or straight configuration
• RF: Right Angle MMCX (subminiature snap-on)
Environmental
Characteristics
Antenna to Receiver
• Single coaxial cable with 6 dB Maximum loss at L1 (active antenna)
Interconnection
• Antenna Sense Circuit
Operating Temperature
• -40°C to +85°C
Humidity
• 95% noncondensing +30°C to +60°C
Altitude
• 18,000 m (60,000 ft.) maximum
• > 18,000 m (60,000 ft.) for velocities < 515m/s (1000 knots)
Miscellaneous
Standard Features
• Motorola DGPS corrections at 9600 baud on COM port one
• RTCM SC-104 input Type 1 and Type 9 messages for DGPS at 2400, 4800
or 9600 baud on COM port two
• NMEA 0138 output
• Inverse DGPS support
Optional features
• Lithium battery
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 2 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
2.
Basic Description
2.1
2.2
Receiver architecture
Channels
12 parallel
Frequency
1575.42 MHz
Code
C/A
Tracking
Carrier aided
Description
The highly integrated single board GPS receiver module is optimized specifically for automotive applications. The
GPS receiver tracks the NAVSTAR GPS constellation of satellites. The satellite signals received by an active
antenna are tracked with 12 parallel channels of L1, C/A code then downconverted to an IF frequency and digitally
processed to obtain a full navigation solution of position, velocity, time and heading. The solution is then sent over
the serial link via the 10-pin connector.
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 3 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
3.
Mechanical
3.1
Mechanical Drawings
3.1.1
M12 Oncore with right angle I/O power/data connector
3.1.2
M12 Oncore with straight I/O power/data connector
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 4 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
3.2
Size
Dimensions
4.
3.3
Weight
3.4
Connectors
40.0 x 60.0 x 10.0 mm
< 25 g
Power/Data
SamTech, FTSH-105-D2-L-DH header, 10 pin, 0.050 inch centers
Antenna RF
Sub-miniature MMCX connector type
Environmental
4.1
Temperature
4.2
Operating
-40°C to +85°C
Storage
-40°C to +105°C
Relative humidity
Operating
4.3
Vibration
5% to 95% non-condensing 30°C to 60°C
0.04 G2/Hz, 20 Hz to 1000 Hz
7.7 G per Military Standard 810E
5.
Electrical
5.1
Pin Outputs
Pin #
Signal
Description
1
TTL TXD1
Transmit 3 V logic
2
TTL RXD1
Receive 3 V logic
3
+3.0 V PWR
+3 V regulated main power
4
1 PPS
One pulse per second signal
5
GROUND
Ground (receiver)
6
BATTERY
Externally applied backup power (2.7 to 3.2 V)
7
Reserved
Not currently used
8
RTCM IN
RTCM input
9
ANTENNA VOLTAGE
3 V or 5 V antenna input voltage
10
Reserved
Not currently used
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 5 of 12
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5.2
Main power
Voltage
2.75 to 3.2 Vdc regulated
50 mV maximum peak-to-peak ripple
Power
5.3
0.225 W maximum (without antenna)
Backup power
Voltage
2.7 V to 3.2 V
Current
5 µA typical @ 2.7 V
Retention
Backup power retains date, time, position, satellite
data and operating mode
5.4
Antenna feed power out of RF connector
Voltage
2.7 V to 3.2 V over current range for 3 V antenna
Current
15 mA to 80 mA
Flags set in serial data when limits exceeded
5.5
5.6
6.
1PPS signal definition
Level
0 V to 3 V
Time mark
Rising edge
Width
200 ms typical
Serial I/O signal definition
Levels
0 V to 3 V, active low
Baud rate
9600
Parity
None
Data bits
8
Start/stop bits
1
RF Characteristics of Receiver
6.1
Dynamic range
27 dB
6.2
Saturation
-110 dBm
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 6 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
7.
RF Requirements for Antenna
7.1
General
Frequency
1575.42 MHz (L1)
Bandwidth
± 1.023 MHz
Polarization
Right hand circular
Impedence
50 Ω
7.2
Gain requirement
10 dB to 26 dB (at receiver input)
7.3
Gain Pattern
+0 dBic minimum at zenith
-10 dBic minimum at 0° elevation
7.4
Noise figure
1.8 dB typical
2.2 dB maximum
7.5
VSWR
1.5:1 typical
2.5:1 maximum
7.6
Axial ratio
3 dB typical at zenith
6 dB maximum at zenith
7.7
1 dB compression point
-14 dBm typical (at antenna output)
7.8
3 dB frequency bandwidth
45 MHz maximum
7.9
25 dB frequency rejection
± 95 MHz
7.10
Ground plane
15 x 15 cm recommended
7.11
Power
Voltage
2.75 V to 3.2 V
3.0 V typical
Current
15 mA typical
25 mA maximum
7.12
Temperature
Operating
-40°C to +85°C
Storage
-40°C to +100°C
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 7 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
8.
Performance
8.1
Accuracy
Position
25 m SEP without SA
100 m 2DRMS (95%) with SA
1 to 5 m typical in differential mode
8.2
Altitude
156 m RMS (95%)
Velocity
0.02 m/s without SA
Time pulse
UTC ± 500 ns with SA on
Dynamic limits
Velocity
515 m/s maximum at altitudes > 18 000 m
Altitude
-1 000 m minimum
18 000 m maximum at velocities > 515 m/s
8.3
8.4
8.5
Acceleration
4 G maximum
Jerk
5 m/s3 maximum
Startup time (TTFF)
50% 90%
Hot (date, time, position, almanac and ephemeris)
15 s
30 s
Warm (date, time, position and almanac)
40 s
65 s
Cold (no stored information)
60 s
210 s
Reacquisition time
After 60 s obstruction
2.0 s
Internal
< 1.0 s
Jamming resistance
Resistant to narrow band CW jamming at the receiver input of +20dBm
RFI
at less than 1525 MHz and greater than 1625 MHz for loss of lock with
a signal input of –130 dBm
Burnout protection
Protected from damage by RF signals at frequencies
100 MHz or more from L1 with received power up to
1 W at the antenna
8.6
EMI
Radiated
Complies with Class B, Part 15 of FCC rules
Conducted
Complies with European CE requirements
Tested to IEC 801-4 spec for fast transients at 500 V, 5/50 ns, 5 kHz
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 8 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
9.
Features
9.1
Differential operation
Motorola binary corrections on TTL RX1
RTCM SC-104 Type 1 and Type 9 corrections on TTL RX2
9.2
9.3
NMEA 0183 output
NMEA 0183
Output on TTL TX1 at 4800 baud
Messages supported
GGA, GLL, GSA, GSV, RMC, VTG, ZDA
User definable datum
One user definable datum may be defined using the @@Ap command. The default datum is WGS-84.
9.4
Antenna sense circuit
The M12 Oncore receiver is capable of detecting the presence of an antenna. The receiver utilizes an antenna
sense circuit, which can detect under current (open) and over current (shorted or exceeding maximum limit)
conditions. The status of the antenna circuit is reported in the Position/Status/Data (@@Ha), the Short
Position Message (@@Hb) and the Self-Test Message (@@Ia).
The antenna sense circuit is useful for verifying that the antenna is properly connected to the receiver and is
drawing the proper amount of current. The antenna sense status should be checked after installation and
monitored regularly.
9.5
Undercurrent indication
< 8 mA
Overcurrent indication
> 80 mA
Real time clock
The real-time clock (RTC) is a standard feature on the M12 Oncore. It is used to minimize the time to first fix
(TTFF). The date and time will be retained in the RTC if battery backup power is applied when main power is
off.
The user has two options regarding time initialization:
1)
Set the date and time BEFORE the receiver acquires any satellites
2)
Let the receiver automatically set the date and time AFTER acquiring the first satellite
Note: The date and time cannot be manually set while the receiver is tracking satellites.
Without battery backup, the receiver will start-up with a default time of 12:00:00. To obtain a faster time to
first fix, the time, date and GMT offset should be initialized if both the main power and battery backup power
have been disconnected.
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 9 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
10.
Serial I/O Messages
10.1
10.2
10.3
Solution
Update rate
1 Hz
Latency
<1s
Reported
Position, velocity, time, satellite status, receiver status, antenna status
Reference
WGS-84 or user defined datum
Resolution
Latitude/longitude
1 milliarcsecond
Height
0.01 m
Velocity
0.01 m/s
Heading
0.1°
Time
1 ns
Solution quality indicators
Receiver status
3D, 2D, propagation, acquisition
Geometry
HDOP when in 2D mode
PDOP when in 3D mode
Satellite status
C/No (dB)
Flag indicating satellite tracking status
Flag indicating satellite is used in solution
10.4
Initialization
Startup mode
Acquisition based on information available
Battery backup provided
No initialization required
No battery backup
Receiver will be in default condition, entering date, time, position and
almanac will speed up acquisition process
Default condition
No serial messages active unless there is a power-on self-test failure
(see Oncore User’s Guide)
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 10 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
10.5
Motorola binary I/O command list
Motorola binary commands can be used to initialize, configure, control, and monitor the GPS receiver. The
Motorola binary commands are supported on the primary communications port at 9600 baud. The commands
supported by the M12 Oncore are:
Ag
Ao
Ap
Aq
As
Au
Ay
Az
AM
AN
AQ
AS
Bb
Be
Bo
Cb
Cf
Ch
Ci
Cj
Ck
Eq
Ga
Gb
Gd
Gj
Gk
Ha
Hb
Ia
Satellite Mask Angle
Datum ID Codes
User Defined Datums
Ionospheric Correction Option
Hold Position Parameters
Altitude Hold Height
1-PPS Time Offset
1-PPS Cable Delay
Position Lock Parameters Message
Marine Filter Message
Position Filter Select
Position Lock Select Message
Visible Satellite Data Message
Almanac Data Request [response is Cb]
UTC Offset Output Message
Almanac Data (output) [response to Be] or
Almanac Data (input) [response is Ch]
Set To Defaults
Almanac Data Response [response to Cb]
Switch I/O Format
Receiver ID
Pseudo-Range Correction Input [response to Ce]
ASCII Position Message
Position Message
Time Message
Position Control Message
Leap Second Pending
Vehicle ID
Position/Status/Data (12 Channel)
Short Position Message
Self-Test Message (12 Channel)
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 11 of 12
It’s Not Where You Are, It’s Where You’re Going.TM
10.6
NMEA Commands
The M12 Oncore supports NMEA 0183 at 4800 baud on the primary communications port. Each of the
supported commands can be output at user selectable update rates. The NMEA commands supported are:
10.7
GGA
GPS Fix Data
GLL
Geographic Position-Latitude/Longitude
GSA
GPS DOP and Active Satellites
GSV
GPS Satellites in View
RMC
Recommended Minimum Specific GPS/Transit Data
VTG
Track Made Good and Ground Speed
ZDA
Time and Date
FOR
Switch to Motorola binary
RTCM Commands
The M12 Oncore accepts RTCM SC-104 Type 1 and Type 9 messages. The messages are input on the second
communications port (pin 8) at a user selectable baud rate of 2400, 4800 or 9600. The RTCM messages are
buffered and processed independently from the primary communications port.
Motorola GPS Products
Phone: 888-298-5217
Fax: 847-714-7325
Preliminary Revision 1.0 3/31/99
www.oncore.motorola.com
Email: g14029@email.mot.com
Page 12 of 12