Radwin 2000+ SERIES - C.2.2 Single Antennas at both Sites; C.2.3 Single at One Site, Dual Antennas at the Other

RADWIN2000+SeriesUserManual Release4.2.40 C‐2
SingleAntennasatBothSites
UponselectingAntennaTypeasDual,aRADWIN2000+Seriesradioautomaticallyselectsthis
modeanddoublestheairrates.
TheRADWINManagerindicates acaseofunbalancedRSSbetweenthetwoantennasinthe
centerpanel.
DiversityMode
DiversityModeusestwoantennastoimprovethequalityandreliabilityofthelink.Often,
thereisnotaclearline‐of‐sight(LOS)betweentransmitterandreceiver.Insteadthesignalis
reflectedalongmultiplepathsbeforefinallybeingreceived.
Eachsuch“bounce”canintroducephaseshifts,timedelays,attenuations,andeven
distortionsthatcandestructivelyinterferewithoneanotherattheapertureofthereceiving
antenna.Antennadiversityisespeciallyeffectiveatmitigatingthesemulti‐pathsituations.
Thisisbecausemultipleantennasaffordareceiversever alrecordingsofthesamesignal.Each
antennawillbeexposedtoadifferentinterferenceenvironment.Thus,ifoneantennais
undergoingadeepfade,itislikelythatanotherhasasufficient signal.Collectivelysucha
systemcanprovidearobustlink.
Antennadiversityrequiresaseparationbetweentheantennas;thisisdonebyusingadual‐
polarization antennaorbytwospatiallyseparatedantennas.
UseDiversity insteadofSpatialMultiplexing inthefollowingsituations:
• WhenthesystemcannotoperateinSpatialMultiplexingMode
• Whenoneofthereceivershashighinterferencecomparedtothesecondreceiver(i.e.
thesystemis“unbalanced”)
• WhenyouachievehighercapacityinDiversityModethaninSpatialMultiplexingMode
• WhenhighrobustnessisofimportanceandthecapacityofDiversityModeissufficient
(upto25Mbpsfullduplex)
C.2.2SingleAntennasatBothSites
Byselectingasingleantennaatbothsites,theradiounitsoperatewithasingleradiothatis
connectedtotheANT1connector.Thesecondradioisautomaticallyshutdown.
C.2.3SingleatOneSite,DualAntennasattheOther
Inthismodeoneofthesitesusestheradiounitwithasingleantennawhiletheothersite
usestheradiounitwithadualantenna.
Theadvantagesinthismodeincomparisontousingasingleantennainbothsitesar e
doubledtotalTxPowerandadditionalpolarizationand/orspacediversity(dependingonthe
polarization ofinstalledantennas).
Theairratesusedinthismodearesameaswhenusingsingleantennasinbothsites.