User manual

43
QUALITYOFSERVICEFORWIRELESSTECHNOLOGYIN
THEWIDEXLINKSYSTEM
WidexLinkwirelesstechnologyenablescommunicationbetween
twopartnersofabinauralpairofDREAMhearingaidsandwith
theirmatchedexternaldevicesTherequirementsforthequality
ofservice(QoS)varyamongthevariouscomponentsandtheirin-
tendeduserscenarios
For programming these requirements include a BER (Bit Error
Rate) betterthan 
-
atabitrateofkbitssasemi-duplex
transmissionwitharequiredacknowledgeatransmissionlatency
ineachdirection(x)andareceive-to-transmitmode(RXtoTX)
timeThedataaresavedinthehearingaidevenwhentransmis-
sionisinterrupted
During daily use therequirements onaudiostreaming between
hearingaidsincludeaBERbetterthan
-
Thecommunicationis
simplexwithabitrateofkbitssTheadditionalaudiodecod-
inginthismoderesultsinalongerlatencywhichislessthan
msForremotecontrolcommandstheQoSrequirementsinclude
aBERbetterthan
-
ThelowerBERrequirementresultsfromre-
dundanttransmissionsEachkeypressresultsintransmissionsof
datapackagesofwhichonlyoneisneededforasuccessfulcom-
munication
Forinter-earcommunicationbetweenhearingaidsaBERbetter
than
-
isrequiredThecommunicationisupdatedeveryms
(orHz)Thehearingaidscontinuetoamplifybasedonthelast
savedsettingsevenwhenthetransmissionrangeisexceededor
whencommunicationisinterfered