Gemalto M2M GmbH MC56 User Manual
MC55/56 Hardware Interface Description
Confidential / Preliminary
Confidential / Preliminary
s
MC55/56_hd_v03.00
Page 66 of 104
16.08.2005
4 Antenna
interface
The RF interface has an impedance of 50Ω. MC55/56 is capable of sustaining a total
mismatch at the antenna connector or pad without any damage, even when transmitting at
maximum RF power.
The external antenna must be matched properly to achieve best performance regarding
radiated power, DC-power consumption and harmonic suppression. Matching networks are
not included on the MC55/56 PCB and should be placed in the host application.
Regarding the return loss MC55/56 provides the following values:
mismatch at the antenna connector or pad without any damage, even when transmitting at
maximum RF power.
The external antenna must be matched properly to achieve best performance regarding
radiated power, DC-power consumption and harmonic suppression. Matching networks are
not included on the MC55/56 PCB and should be placed in the host application.
Regarding the return loss MC55/56 provides the following values:
Table 20: Return loss
State of module
Return loss of module
Recommended return loss of application
Receive
> 8dB
> 12dB
Transmit
not applicable
> 12dB
Idle
< 5dB
not applicable
The connection of the antenna or other equipment must be decoupled from DC voltage.
4.1 Antenna
installation
To suit the physical design of individual applications MC55/56 offers two alternative
approaches to connecting the antenna:
• Recommended approach: U.FL-R-SMT antenna connector from Hirose assembled on
approaches to connecting the antenna:
• Recommended approach: U.FL-R-SMT antenna connector from Hirose assembled on
Figure 26: U.FL-R-SMT connector
Figure 27: Antenna pad and GND plane
Antenna pad
Antenna ground