Multi-Tech Systems MTCBA-E-EN User Manual

Appendix B – Wireless Antenna 

Multi-Tech Systems, Inc. MultiModem Wireless Modem with Ethernet Interface (S000375F) 

 

 

 

 

The antenna sub-system and integration in the application is a major issue: Choice of antenna (type, length, 
performances, thermal resistance, etc.) These elements could affect GSM performances such as sensitivity and 

emitted power. 

There cannot be any alteration to the authorized antenna system. The antenna system must be the same 

type with similar in-band and out-of-band radiation patterns and maintain the same specifications.  

The antenna gain, including cable loss, must not exceed 3.0 dBi at 1900 MHz / 1.6 dBi at 850 MHz for 
mobile operating configurations and 7.0 dBi at 1900 MHz / 2.3 dBi at 850 MHz for fixed mounted 
operations, as defined in 2.1091 and 1.1307 of the rules for satisfying RF exposure compliance. 

 

The integrated modem antenna connector is a SMA connector.

 

The SMA connector incorporates a 'Screw-on'  

action in order to make the connection easier while providing an excellent RF performance. An additional 

advantage is its small physical size, which is 50% of the standard MCX connector. 
This type of connector is suitable for the standard ranges of flexible and semi-rigid cables. The characteristic 

impedance of the MMCX coaxial connector is 50 ohm. The antenna manufacturer must guarantee that the 
antenna will be working according to the radio characteristics presented in the table below. 
 

 

 

869 to 894 MHz 

925 to 960 MHz

1805 to 1880 MHz 

1930 to 1990 MHz

824 to 849 MHz 

880 to 915 MHz

1710 to 1785 MHz 

1850 to 1910 MHz

2W at 12.5% duty cycle 2W at 12.5% duty cycle 1W at 12.5% duty cycle  1W at 12.5% duty cycle

                                                  50 ohms

                                                      <2

     0 dBi on azimuth plane

 

869 to 894 MHz

1930 to 1990 MHz 

824 to 849 MHz

1850 to 1910 MHz 

                          50 ohms

                             <2

              0 dBi in at least one direction