User's Manual

SIM800H Document
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4.2. Module RF Receive Sensitivity
The following table shows the module’s conducted receive sensitivity, it is tested under static condition.
Table
10: SIM800H conducted RF receive sensitivity
Frequency
Receive sensitivity
˄
Typical
˅
Receive sensitivity(Max)
GSM850 -108dBm -106dBm
EGSM900 -108dBm -106dBm
DCS1800 -108dBm -106dBm
PCS1900 -108dBm -106dBm
4.3. Module Operating Frequencies
The following table shows the module’s operating frequency range; it is followed by the 3GPP TS 05.05 technical
specification requirement.
Table
11: SIM800H operating frequencies
Frequency Receive Transmit
GSM850 869 ~ 894MHz 824 ~ 849 MHz
EGSM900 925 ~ 960MHz 880 ~ 915MHz
DCS1800 1805 ~ 1880MHz 1710 ~ 1785MHz
PCS1900 1930 ~ 1990MHz 1850 ~ 1910MHz
5. Antenna interface
There are three antenna ports for SIM800H, GSM antenna port named RF_ANT, Bluetooth antenna port named
BT_ANT and FM antenna port named FM_ANT_P, The RF interface of the three antenna ports has an
impedance of 50.The maximum gain of the GSM antenna gain should not exceed 3dBi considering the SAR
radio. And the maximum gain of the Bluetooth antenna gain shout not exceed 2dBi.1RDQWHQQDJDLQPD\EHXVHG
WKDWZRXOGH[FHHGWKH:(,53SRZHUOLPLWLQ0+]EDQG
z The input impendence of the antenna should be 50, and the VSWR should be less than 2.
z It is recommended that the GSM antenna and the BT antenna be placed as far as better.
z The isolations of the three antenna should be bigger than 30d
%

5.1 GSM Antenna Interface
There is a GSM antenna pad named RF_ANT for SIM800H the connection of the antenna must be decoupled
from DC voltage. This is necessary because the antenna connector is DC coupled to ground via an inductor for
ESD protection.
The external antenna must be matched properly to achieve best performance, so the matching circuit is
necessary, the connection is recommended as following: