TheJG-His a self-contained trailer tracking device that combines GPS location with
WCDMA/GSM/GPRSconnectivity.It is primarily a location reporting device that responds to
requests (user, server) and events (timers, geo-fences). Data reports consist of a sing le record
that contains all location data and system status.
The device comes pre-configured from the factory, ready to use.TheJG-H appears to a user or
a server application as a single endpoint device. It can be queried, updated and configured
either through a serial connection, an over the air IP connection, or through SMS messaging.
TheJG-Hpresents itself over these co nnections as an enhanced cellular modem with attached
functional elements. These elements include:
• GPS
• Accelerometer
• I/O pins and tamper alert
• Serial UART port for management and for cargo sensor
• Status LEDs
• Timers
• Watchdog lockup protection
• Power Management
• Power Output
• Solar panel power supply
Access to these elements and general purpose interfaces is done through an extended AT
command set as defined herein.Configuration parameters ar e stored to flash memory and
are automatically used on the next power up event. For more d etails, please reference the
AT Command document.
This product is designed based on the MT6276 Baseband chipset, supporting WCDMAand
GPRS protocol for wirelessdata; using an internal dual band antenna(GSM850&PCS 1900).
The device also includes stand-alone GPS functionality, an accelerometer for motion
detection, as well as support for solar panel power supply. The JG-H can operate from an
internal rechargeable battery or an external power source. The battery is recharging via the
solar panel or external power.
2 Hardware Design
2.1 Basic Hardware
RF 3G Transceiver
Memory
Antenna
GPS Antenna
RF7411TR7
2G band support : 850MHz & 1.8GHz
Support for 12 class GPRS
3G band support : Band2 and Band5
Internal Antenna[850M&1900M]
Dedicate high performance ceramic antenna
No-UIM mode, SIM card connector
On: Indicates external power and batter y is fully charged
: Indicates running from battery. Blinks shortly every
30sec.
Battery
Power Out
Solar Panel
Power Consumption
The JG-Hprovides support for specialized hardware f eatures th roug h extend ed AT commands.
The features supported include the following.
Built in rechargeable batteryfor up to 6 months
Yes
Yes
<20 Watts
GPS
GPS location functionality is provided by the device GPS receiver. Warm start from sleep is
supported.
GPIO
One general purpose GPIO and three additional mul tiplex ed IO’ s are presented to the exter nal
environment on the main connector. They are capable of providing system interrupts to
generate a report or drive logic l evels to ex ternal d evi ces. The se lin es are 2 .8V l ogic lev el an d
are 16V tolerant. The multiplexed IO’s are typically configured as Ignition, Relay and
Tamper.
LED’s
Three LED status indicators are provided to verify correct installation and operation. The
status LEDs are color coded and directly convey the status of the cellular and GPS
subsystems, as well as the power input; describ ed in the table below. Their valid operation
also indicates operational status and power.
LED Function Status
Red GPS
On: GPS satellites acquired and locked
Flash Slow: GPS satellite search is in progress
Indicates cellulardata connection is available
Connection
charging
The JG-H provides user control allowing the LEDs to be extinguished once installation is
verified. This feature reduces power and further conceals the JG-H Tracker from untrained
parties wishing to defeat its operation.
Flash Slow: cellular subsystem initialized but no connection
Flash Fast: cellular initialization in process
Flash: Indicates external power and battery i s charging
Off
Remark
Accelerometer
The accelerometer is used for motion start detectio n to wake the unit up from a sleep mode
and driving behavior monitoring.
UART
A UART port is provided for AT command and data interaction. The UART can also serve to
attach other accessories, such as cargo sensor.
1-Wire
A 1-Wire interface is supported to attach ext er nal sensors, such as temperature sensor, etc.
Relay Driver
A 500mA sink capable output pin is provided. This pin is meant to drive a relay coil indented
to interrupt the starter solenoid relay for the ignition circuit to a car.
Ignition Monitor
One of the GPIO’s can be wired to vehicle ignit ion to monitor and trigger event upon ignition
start and stop.
Power Out
The JG-H provides a power out option at 3.3V and up to 300mA to enable powering up
external devices. The power out is turned off by default and is controlled by software.
Tamper
Tamper detection pin is available on the external connector. The Tamper pin can trigger an
alert when disconnected from ground.
Solar Panel
The JG-H includes an integrated solar p anel that co nstantly charges the battery when exposed
to light.
Power Monitor
The internal power monitor circuitry allows to measure the voltage on all possible power
sources: Main, Auxiliary, Battery, Solar.
Timers
Timers resident on the baseband chip generate periodic interrupts for power down, wakeup,
report generation and other timer related functions.
The code domain power in each inactive code channel
below the total output power
Conducted spurious emission
(test2: -60dBm/1.23MHz) -10.7±9.5dBm
WCDMA Band1 RX
Maximum output power 21~24dBm
Minimum controlled output
<-50dBm
power
WCDMA Band1 TX
3G Frequency range 1920MHz~1980MHz
Maximum Frequency error ±200KHz
Maximum output power 21~24dBm
Minimum controlled output
<-50dBm
power
Standby output power <-61dBm
Error Vector Magnitude <17.5%
DCS Band RX
Frequency range 1805MHz ~ 1880MHz
Sensitivity -108dBm (FER≤0.5%)
Dynamic range -25 ~ -108dBm (FER≤0.5%)
Single tone Desensitization -102.4dBm(FER≤1%,-40dBm@±1250KHz)
Intermediation Spurious
Response Attenuation
-102.4dBm(FER≤1%,-43dBm@±1250KHz/±2050KHz)
<-76dBm/1MHz(RX band)
Conducted Spurious
Emission
<-61dBm/1MHz( TX band)
<-47dBm/30KHz(other frequency)
Maximum Frequency error ±200KHz
Maximum output power 23 ~ 30dBm
Minimum controlled output
Code domain power
Time reference ±1.0uS
Waveform quality >0.944
Range of open loop output
power
The JG-Hsupports OTA field upgrades of the JG-Hresident application. An over the air TFTP
(Trivial File Transfer Protocol) connection is made over a UDP/IP connection. A replacement
file is then transferred from a server to the JG-Hand that fil e replaces the previou s application
image.
3.3 Power Modes
The JG-H device supports several power modes that are set by AT commands. In full power
mode the GPS is active and the cellular subsystem will maintain a persistent cellular
connection whenever service is available. IP connection is maintained according to the
configuration of the device.
The device can be put in a sleep mode whenever it runs on an internal battery, if the external
battery is low or if the device is not moving. In low power mode the GPS is not running and
the LED’s are off. The device would return to full power whenever an event occurs that
triggers a report. Those events include:
• GPIO change
• Battery threshold
• Heartbeat
• Power-up
• Accelerometer
• Tamper
Any hardware or software reset will return the device to full power mode.
JG-Hcommands are AT extensions specific to JG-H devices. They are closely based on
commands that are as similar as possible to other industry common devices. Native AT
commands supported by the baseband modem are also available via the serial interface.
Command Summary
The following commands are specific to the JG-H. They are organized by categories.
Event Setting Commands
The following set of commands enables/disables reporting of the various events and state
transitions that take place in the system. The event setting commands typically include
trigger(s) that indicate what event or st ate transition would cause an event report to b e sent.
Often state transitions also qualified with “debounce” time to prevent various flickers and
intermittent state transitions. Examples are: (1) state change of an input pin; (2) crossing a
geo-fence line for a brief period of time and then crossing it back.
As a general rule every event and stat e transition has its own un ique event ID t hat is reflecte d
in the report triggered by the said event. Refer to Table 2 – Events for the co mplete list of
event ID’s. Those default event ID’s can be changed by the user to accommodate specific
server implementations, by explicitly specify ing what they are in the respective commands.
As an example, all trip related event s can be mapped to the same ev ent ID, so there is no need
to parse the specific event trigger. Following i s a list of event setting commands:
Periodic Action commands trigger time based periodic action, such as reset, data session
renewal, etc. Some actions can trigg er an event report to indicate the respective action took
place. Following is a list of event setting commands:
41. AT+XKA Keep Alive
42. AT+XPST Packet Session T imeout
43. AT+XRSTP Reset Periodically
Configuration Commands
Configuration commands control various parameter settings of the device. For convenience
they are grouped into topical settings. Following is a list of configuration commands:
Communication related settings
44. AT+XAPN Set APN (GSM devices only)
45. AT+XCSW Cellular Session Watc hdog
46. AT+XIP Set target server IP address and port number
47. AT+XLPORT Set Local IP port number
48. AT+XMIP Set Maintenance server IP address and port number
49. AT+XPRP PxP Renewal Policy
50. AT+XSMSD SMS Destination
51. AT+XSMSS SMS Source
52. AT+XSPIP Set Serial Port (A-UART) IP address and port number
53. AT+XUIP Set Update server IP address and port number
Information commands simply output various data regarding the current status of the device.
They are mostly useful for troubleshooting. Following is a list of information commands:
The JG-H captures data and forms a repor t record with that data. A report is a data struct ure
containing all of the sensory and other typically useful data on the device. Reports are
generated in response to specified events, such as periodic timeout, speed threshold,
geo-fence crossing, etc., or in response to a Repo r t Now command (AT+XRN).
Report Queuing
If a report trigger occurs while UDP connection is unavailable, it will be queued until
connection becomes available and transmitted at such time. The only way report(s) can be lost
is if too many reports are queued and the report-queue is overflowing. In such case the earliest
report(s) will be discarded. The size of the queue can be configured via the Report Queue
(AT+XRPQ) command.
Ack’ed Mode
UDP is not a 100% reliable connection and o ccasional reports or co mmand/responses may be
lost. Since all commands have respon ses, the server can repeat any command to which there
is no response. In order to assure reliable reception of reports, the device can be configured
either in Normal or Ack’ed mode to send the reports. In the Normal mode the reports are
simply sent “as is” with no acknowledgment from the server. In the Ack’ed mode every
report sent is expected to be acknowle dged by the server by sending back an ACK messag e
back. If acknowledgement is not received within th e specified ti meout, the rep ort is re-sent. I f
the report is not acknowledged after the specified number of attempts, it is queued. If
acknowledgement is received after the rep ort is queued (i.e. past timeout of the last atte mpt),
it is ignored.
Report is not considered “complete” until its ackn owledgement is received. Thus, if repo rt X
is sent and report X+1 is triggered while waiting for acknowledgement of X, report X+1 will
be queued until such acknowledgement is received and only then sent. The JG-H will attempt
to re-send queued report(s) every time a new report is triggered. If there is more than one
report queued, the reports will attempt to be sent in the order of triggering and only once the
report is acknowledged, the next report is attempted. This assures that reports are sent and
received in order.
Ack’ed mode assures that all reports are r eceived, but adds ov erhead in time and data. Report
that is not acknowledged is sent again and eventually will be queued and sent again. The
number and frequency of re-tries is configurable via the Report Acknowledgement command
(AT+XRPA).
There are a number of resets availabl e on the device. Soft reset o nly restarts the baseband on
the device. Hard reset is caused by resetting the whole b aseband module v ia a reset p in. There
is also an option to reset the cellular and GPS sub-systemsindividially.
3.5.1 Context Preservation
When a self-initiated reset is performed due to Network Watchdog or by the Reset command
(modes 0,1), the context of the system is being p reserved and is restored after the reset. The
context includes all the periodic timers, the report queue, the odometer, etc. This allo ws to
reset the unit as a troubleshooting or preventive measure without losing reports that are
already in the queue or are pending on running timers. Note that the reset process may cause
1-2min of inaccuracy in the timers and should not be considered as very precise.
3.6 Startup Banner
After a reset a startup banner is printed through the UART only.
The antenna(s) used for this transmitter must be installed to provide a separation distance of at
least 20 cm from all persons during the normal operations.
This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection
against harmful interference in a residential installation. This equipment generates uses and can
radiate radio frequency energy and, if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment
off and on, the user is encouraged to try to correct the interference by one or more of the following
measures:
-- Reorient or relocate the receiving antenna.
-- Increase the separation between the equipment and receiver.
-- Connect the equipment into an outlet on a circuit different from that to which the receiver is
connected.
-- Consult the dealer or an experienced radio/TV technicia n for help.
This device complies with part 15 of the FCC Rules. Operation is subject to the following two
conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.
Changes or modifications not expressly approved by the party responsible for compliance could
void the user's authority to operate the equipment.
IC STATEMENT
This device complies with Industry Canada licence-exempt RSS standard(s). Operation is subject
to the following two conditions: (1) this device may not cause interference, and (2) this device
must accept any interference, including interference that may cause undesired operation of the
device.
Le présentappareilestconforme aux CNR d'Industrie Canada applicables aux appareils radio
exempts de licence. L'exploitationestautorisée aux deux conditions suivantes : (1) l'appareil ne doit
pas produire de brouillage, et (2) l'utilisateur de l'appareildoit accepter tou t
brouillageradioélectriquesubi, mêmesi le brouillageest susceptible d'encompromettre le
fonctionnement.
In order to avoid the possibility of exceeding the IC radio frequency exposure limits, human