Enfora MLG0208PB001 用户手册

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Enfora Enabler II-G Assisted GPS 
Modem Integration Guide 
The SDK117 has three antenna cables.  One cable is for connection to the RF connector for 
quad band GSM/GPRS antenna.  The second RF cable is for a passive PCB patch antenna 
that can be used for the GSM/GPRS antenna.  The third antenna is for the passive GPS patch 
antenna.   
 
However, if the GPS antenna is more than 10 cm away from the module (a likely scenario), 
one should consider using an active GPS antenna.  An active antenna has an integrated low 
noise amplifier (LNA) and needs power to activate this circuit and for the antenna to work.  
 
For optimum operation, the maximum in band input RF level into the Enfora Enabler II-G A-
GPS GPS antenna port should not exceed –95 dBm. If this condition exceeds, the 
subsequence analog gain stage in the GPS chip set may saturate causing degradation in 
overall system performance. Out of band RF level in excess of –70 dBm at the antenna port 
may also cause system degradation. Because most active antenna do not provide out of band 
rejection with a high Q filter, end users should take special precaution in selecting the active 
gain versus cable loss.  A quality patch antenna can easily provide in band gain of 3 to 5 dBi 
and out of band gain of 0 dBi, together with the LNA gain, it can boost out of band signal above 
the –70 dBm range.  
 
Please refer to MLG0208TN001 – External Active GPS Antenna Design Guide for MLG0208 A-
GPS Module.
  
 
 
6.5.1.  Antenna Solder Pads 
 
Pads are provided to solder a cable or antenna directly to the Enabler II-G A-GPS board. 
 
6.5.2.  GSM Antenna Connector 
 
The Enabler II-G A-GPS module utilizes an ultra Miniature Coaxial Interconnect from 
Sunridge (MCB-ST-00T) as the on-board antenna connector.  A compatible mating 
connector is the Sunridge MCB2-xx-xx-xxx-x series component.  The cable assembly is 
made to order.  Maximum stack height of cable connector and PCB connector is 2.0 mm. 
 
6.5.3.  GPS Antenna Connector 
 
The Enabler II-G A-GPS module utilizes an ultra Miniature Coaxial Interconnect from 
Sunridge (MCB-ST-00T) as the on-board GPS antenna connector.  A compatible mating 
connector is the Sunridge MCB2-xx-xx-xxx-x series component.  The cable assembly is 
made to order.  Maximum stack height of cable connector and PCB connector is 2.0 mm. 
 
NOTE
:  For both the GSM Antenna Connector and the GPS Antenna Connector, please 
refer to Figure 7 MCB2 Cable Assembly.  This diagram will help you determine the 
exact part number you will need to build the cable.  For more detailed information, please 
refer to the Sunridge website at 
.  
 
 
MLG0208PB001 
25 
Version1.01 – 10/3/2006