Huawei ME909 manual Antenna Design Requirements, Antenna Design Indicators

Page 29

HUAWEI ME909 Series Mini PCIe Module

 

Hardware Guide

RF Specifications

4.5 Antenna Design Requirements

4.5.1Antenna Design Indicators

Antenna Efficiency

Antenna efficiency is the ratio of the input power to the radiated or received power of an antenna. The radiated power of an antenna is always lower than the input power due to the following antenna losses: return loss, material loss, and coupling loss. The efficiency of an antenna relates to its electrical dimensions. To be specific, the antenna efficiency increases with the electrical dimensions. In addition, the transmission cable from the antenna connector of PCIe Adapter to the antenna is also part of the antenna. The cable loss increases with the cable length and the frequency. It is recommended that the cable loss is as low as possible, for example, MXHP32HP1000 made by Murata or equivalent.

The following antenna efficiency (free space) is recommended for ME909 module to ensure high radio performance of the module:

Efficiency of the primary antenna: ≥ 40% (below 960 MHz); ≥ 50% (over 1710 MHz)

Efficiency of the diversity antenna: ≥ half of the efficiency of the primary antenna in receiving band

Efficiency of the GPS antenna: ≥ 50%

In addition, the efficiency should be tested with the transmission cable.

S11 or VSWR

S11 indicates the degree to which the input impedance of an antenna matches the reference impedance (50 Ω). S11 shows the resonance feature and impedance bandwidth of an antenna. Voltage standing wave ratio (VSWR) is another expression of S11. S11 relates to the antenna efficiency. S11 can be measured with a vector analyzer.

The following S11 value is recommended for the antenna of ME909 module:

S11 of the primary antenna: ≤ –6 dB

S11 of the diversity antenna: ≤ –6 dB

S11 of the GPS antenna: ≤ –10 dB

In addition, S11 is less important than the efficiency, and S11 has weak correlation to wireless performance.

Isolation

For a wireless device with multiple antennas, the power of different antennas is coupled with each other. Antenna isolation is used to measure the power coupling. The power radiated by an antenna might be received by an adjacent antenna, which decreases the antenna radiation efficiency and affects the running of other devices. To avoid this problem, evaluate the antenna isolation as sufficiently as possible at the early stage of antenna design.

Antenna isolation depends on the following factors:

 

Huawei Proprietary and Confidential

29

Issue 0.1 (2013-06-09)

Copyright © Huawei Technologies Co., Ltd.

 

Page 28 Page 30
Image 29
Page 28 Page 30
Contents Hardware Guide Issue DateNo Warranty Document Date Chapter Descriptions Version About This DocumentRevision History Contents Certifications FCC Statement Product name Description State Introduction1ME909 series product name Overall Description Feature DescriptionAbout This Chapter Function OverviewLEDWWAN# Active-low LED signal indicating the state Circuit Block DiagramMini PCIe Interface Description of the Application InterfacesVCC3V3 WAKE#COEX1 GNDWDISABLE# UimresetUimpwr UimdataSmbdata SmbclkUsbd Usbdm USBD+ UsbdpPin No Pin Name Minimum Typical Maximum Power Sources and GroundsPower Valid to USB + high Power Supply Time SequenceCutting off 3.3 V will power off the module Parameter Remarks Time Nominal value UnitResinn Signal WAKE# Signal6Reset pulse timing USB Interface WDISABLE# SignalLEDWWAN# Signal Pin Pin Name Description DC Characteristics Min Typ Max Pin No Pin Name Description DC Characteristics Min Typ MaxUsim Card Interface OverviewExternal 2.85 Usim card Circuit Recommended for the Usim Card InterfaceAudio Interface Pin Pin Name Description DC Characteristics Min TypPCM clock PCM data inputRF Antenna Connector NC Pins Reserved PinsPin No Pin Name Description Reserved Reserved, please keep openNC pins Operating Band RF SpecificationsOperating Frequencies Conducted RF Measurement Conducted Rx Sensitivity and Tx PowerTest Environment Test StandardsType Value Band TypicalTBD Modulation RB Allocation MPRdB Conducted Transmit PowerQpsk 16QAMAntenna Design Requirements Antenna Design IndicatorsPolarization 3 GSM/WCDMA/GPS Antenna Requirements InterferenceFrequency range Radio Test EnvironmentOperator, the customer must use the most suitable Antenna for that/those bandsPassive Tests Symbol Specification Min Max Unit Electrical and Reliability FeaturesExternal power voltage Digital input voltage Absolute RatingsElectrical Features of Usim Operating and Storage Temperatures and HumidityElectrical Features of Application Interfaces Specification Min Max UnitInput Power Supply Power Supply FeaturesPower Module Peak GSM Normal Normal LTE Slot Parameter Min Typ Max Ripple UnitDescription Bands Test Value Units Power ConsumptionHsdpa Description Band Test Value Units Power dBmWcdma LTE 23dBm Tx PowerIMT2100 Description Test Value Units ConfigurationGPRS850 TBD GPRS900 TBDEDGE900 TBD Description Max Test Value Units ConfigurationEDGE850 TBD Test Condition Standard Reliability Features− UIM − USB EMC and ESD FeaturesHuawei Proprietary and Confidential Issue 0.1 Dimensions and Interfaces Mechanical Specifications1Dimensions of the ME909 module Dimensions of the Mini PCI Express ConnectorInstalling the Mini PCIe Adapter on the Main Board Specification Selection for FastenersHuawei Proprietary and Confidential Issue 0.1 Removing the Mini PCIe Adapter from the Main Board Page Certifications CertificationsCertification Model name ME909u-521 GCF WeeeInterference Safety InformationMedical Device Area with Inflammables and ExplosivesTraffic Security Safety of ChildrenAirline Security Environment ProtectionLaws and Regulations Observance Care and MaintenanceEmergency Call Regulatory InformationFCC Statement Appendix a Circuit of Typical Interface Acronym or Abbreviation Expansion Appendix B Acronyms and AbbreviationsHsupa HSPA+ISO LCP
Related manuals
Manual 13 pages 25.55 Kb
Top Page Image Contents