RADWIN2000+SeriesUserManual Release4.2.40 C‐1
AppendixC:SettingAntenna
Parameters
C.1AntennaIssues
Beforeproceedingtoantennainstallationdetails,thefollowingbackgroundinformation
shouldbeconsidered:
C.2AboutSingleandDualAntennas
EachRADWIN2000+SeriesODUismadeoftworadiotransceivers(radios).Theradiosmake
useofalgorithmsthatutilizebothSpatialMultiplexingandDiversityresultinginenhanced
capacity,rangeandlinkavailability.Thenumberofantennasusedisdeterminedbyuser
configurationandbyautomaticsystemdecisions,explainedbelow.
C.2.1DualAntennasattheRT‐A(HBS)andRT‐B(HSU)
Whenusingdualantennasatbothsites(singlebipolarantennaortwounipolarantennas)you
canchoosebetweenSpatialMultiplexingModeandDiversityMode.
SpatialMultiplexingMode
Underthismode,thesystemdoublesthelinkcapacity.Atthesametime,itkeepsthesame
rateandmodulationperradioaswasusedwithsingleantenna,thusincreasingcapacity,
rangeandavailability.
Forexample,at80MHzCBW,usingadualantenna,aRADWIN2000D+radiounitcantransmit
atmodulationof256QAMandFECof5/6andgetanairrateof866.7Mbps,comparedto
433.3Mbpswithsingleantenna.
Toworkinthismode,eachantennaportmustbeconnectedtoanantenna,theRSSlevelin
bothreceiversshouldbebalancedandaminimalseparationbetweentheantennasmustbe
maintained.(Forex ample,byusingdualpolarizationantennasacrosspolarizationseparation
isattained).