Apache Labs ANDROMEDA ANAN-7000DLE MKII - 6.4.4 Noise Blanking & Reduction; 6.4.5 Diversity Operation; 6.5 RIT, XIT Tuning

ANDROMEDAManual Page30of56
6.4.4 NoiseBlanking&reduction
Variousmeanstoreducenoiseareavailable.Thetishasmodern,powerfulalgorithmsavailableto
optimiseitsperformance.ThesecontrolscanbeaccessedthroughtheRXMenu.
NR Activatesnoisereduction,tominimiserandomnoise.Thisattemptstoreducethe
noiseinthechannelwhilepreservingsignalcontent.
Off: Noisereduction
inactive
NR: ActivatestheLMSnoisereductionalgorithm
NR2: Activatesthespectralnoisereductionalgorithm
NB Activatesthewidebandnoiseblanker,toremoveimpulseinterference.
Off: NoiseBlankerinactive
NB: NoiseBlankeractive,andsetsreceiverinputtozeroduringimpulse
NB2: NoiseBlankeractive,andestimatesthesignalthereceiver
would
haveseenduringanimpulse.
ANF ActivatestheAutomaticNotchFilter.Thisfilterwillattempttonotchoutinterfering
carriersignalswithinthereceiverpassband.
SNB ActivatesthespectralNoiseBlanker.TheSNBdetectsimpulseinterferenceand
attemptstoestimatethe“correct”receiversignalduringthepresenceofthe
impulse.
6.4.5 Diversity
Diversityallowstheradiotoimplementbeamforming.Thisrequirestwofullyindependentinputs,
onethrougheachA‐Dconverter,fromtwoantennas.Thiscanbeusedtoenhanceaweaksignal,or
tosteeranulltowardsaninterferencesource.DiversityimprovesthereceivedsignalforRX1,butis
independentof
theoperationofRX2.RX2canbeusedonadifferentbandifdesired;theonly
constraintisifitisonadifferentband,itsRXfilterswillneedtobedisabled.
Tousediversity:
1. SelecttheMenu>DiversitymenuitemtoopentheDiversityformor
usetheDiversity
buttonontheRXmenu.
2. SetReceiversourcetoRX1+RX2
3. SetreferenceSourcetoRX1
4. Tominimiseinterference:
a. UsetheDiversityPhase(lower)encodertomovethedotaroundthedisplay
b. Youshouldseethepanadapternoisefloormoveupanddownasyoudrag
c. Findtheanglegivingminimumnoisefloor
d. Keepingthemouseatthatangle,UsetheDiversity
Gainencodertofindthe
optimumamplitudewithminimumnoise
e. Ifyouaren’tabletogetaminimum:SetreferenceSourcetoRX2andtryagain
5. Tomaximisestrengthofonesignal:
a. UsetheDiversityPhase(lower)encodertomovethedotaroundthedisplay
b. Findtheanglegivingmaximumsignalonthepanadapterforthewantedsignal
c. Keepingthemouseatthatangle,UsetheDiversityGainencodertofindthe
optimum
amplitudewithmaximumsignal
d. Ifyouaren’tabletogetamaximum:SetreferenceSourcetoRX2andtryagain
6. Toturndiversityoff,ClickEnabledanditwillturntoaredDisabledbutton.
6.5 RIT,XIT
RXandTXindependenttuningallowsyoutoadapttheradiotoremotestationsthatarenottunedto
theexactsamefrequency.RITandXITarecontrolledbyanencoderwhosefunctioncanbesettooff,
RITorXIT.Indicatorsshowwhichisactive.