ZTE Corporation MG2636 Manuale Utente
MG2636 module
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the module will help obtain superior performance. High Quality/Low loss co-axial cables should be used to
connect the antenna to the RF connectors. Contact the antenna vendor for the specific type of cable that
interfaces with their antenna and ask them to detail the RF losses of the cables supplied along with the antenna.
Typically, the cable length should be such that they have no more than 1-2dB of loss. Though the system will
work with longer (lossy) cables, this will degrade GSM system performance. Care should also be taken to
ensure that the cable end
connectors/terminations are well assembled to minimize losses and to offer a reliable, sturdy connection to the
Module sub-system. This is particularly important for applications where the module is mounted on a mobile or
portable environment where it is subject to shock and vibration.
connect the antenna to the RF connectors. Contact the antenna vendor for the specific type of cable that
interfaces with their antenna and ask them to detail the RF losses of the cables supplied along with the antenna.
Typically, the cable length should be such that they have no more than 1-2dB of loss. Though the system will
work with longer (lossy) cables, this will degrade GSM system performance. Care should also be taken to
ensure that the cable end
connectors/terminations are well assembled to minimize losses and to offer a reliable, sturdy connection to the
Module sub-system. This is particularly important for applications where the module is mounted on a mobile or
portable environment where it is subject to shock and vibration.
6.4.3 Antenna Gain Maximum Requirements
Our FCC Grant imposes a maximum gain for the antenna subsystem: 2 dBi for the GSM850 band and 2dBi for
the 1900 band.
the 1900 band.
Warning: Excessive gain could damage sensitive RF circuits and void the warranty.
6.4.4
Antenna Matching
The module’s RF connectors are designed to work with a 50-ohm subsystem. It is assumed that the antenna
chosen has matching internal to it to match between the 50-ohm RF connectors and the antenna impedance.
chosen has matching internal to it to match between the 50-ohm RF connectors and the antenna impedance.
6.4.5 PCB Design Considerations
• The antenna subsystem should be treated like any other RF system or component. It should be isolated as
much as possible from any noise generating circuitry including the interface signals via filtering and shielding.
• As a general recommendation all components or chips operating at high frequencies such as
micro controllers, memory, DC/DC converts and other RF components should not be placed too close to the
module. When such cases exist, correct supply and ground de-coupling areas should be designed and validated.
• Avoid placing the components around the RF connection and close to the RF line between the RF antenna and
the module.
• RF lines and cables should be as short as possible.
• If using coaxial cable it should not be placed close to devices operating at low frequencies. Signals like
charger circuits may require some EMI/RFI decoupling such as filter capacitors or ferrite beads.
• Adding external impedance matching to improve the match to your cable and antenna assemblies is optional.
Please contact the antenna vendor for matching requirements.
• For better ESD protection one can implement a shock coil to ground and place it close to the RF connector.
much as possible from any noise generating circuitry including the interface signals via filtering and shielding.
• As a general recommendation all components or chips operating at high frequencies such as
micro controllers, memory, DC/DC converts and other RF components should not be placed too close to the
module. When such cases exist, correct supply and ground de-coupling areas should be designed and validated.
• Avoid placing the components around the RF connection and close to the RF line between the RF antenna and
the module.
• RF lines and cables should be as short as possible.
• If using coaxial cable it should not be placed close to devices operating at low frequencies. Signals like
charger circuits may require some EMI/RFI decoupling such as filter capacitors or ferrite beads.
• Adding external impedance matching to improve the match to your cable and antenna assemblies is optional.
Please contact the antenna vendor for matching requirements.
• For better ESD protection one can implement a shock coil to ground and place it close to the RF connector.
Antenna Interface
Proper measures should be taken to reduce the access loss of effective bands, and good shielding should be
established between the external antenna and the RF connector. Besides, the external RF cables should be kept
far away from all interference sources such as high-speed digital signal or switch power supply.
According to mobile station standard, stationary wave ratio of antenna should be between1.1 to 1.5, and input
impedance is 50 ohm. Different environments may have different requirements on the antenna’s gain. Generally,
the larger gain in the band and smaller outside the band, the better performance the antenna has. Isolation
degree among ports must more than 30dB when multi-ports antenna is used. For example, between two
different polarized ports on dual-polarized antenna, two different frequency ports on dual-frequency antenna, or
among four ports on dual-polarized dual-frequency antenna, isolation degree should be more than 30dB.
established between the external antenna and the RF connector. Besides, the external RF cables should be kept
far away from all interference sources such as high-speed digital signal or switch power supply.
According to mobile station standard, stationary wave ratio of antenna should be between1.1 to 1.5, and input
impedance is 50 ohm. Different environments may have different requirements on the antenna’s gain. Generally,
the larger gain in the band and smaller outside the band, the better performance the antenna has. Isolation
degree among ports must more than 30dB when multi-ports antenna is used. For example, between two
different polarized ports on dual-polarized antenna, two different frequency ports on dual-frequency antenna, or
among four ports on dual-polarized dual-frequency antenna, isolation degree should be more than 30dB.