25
QualityofServiceforWirelessTechnologyintheWidexLink
System
WidexLinkwirelesstechnologyenablescommunicationbetween
twopartnersofabinauralpairofCLEARhearingaidsandwith
theirmatchedexternaldevicesTherequirementsforthequalityof
service(QoS)varyamongthevariouscomponentsandtheirin-
tendeduserscenarios
For programming these requirements include a BER (Bit Error
Rate)betterthan
-
atabitrateofkbitssasemi-duplex
transmissionwitharequiredacknowledgeatransmissionlatency
ineachdirection(x)andareceive-to-transmitmode(RXtoTX)
timeThedataaresavedinthehearingaidevenwhentransmis-
sionisinterrupted
Duringdailyusethe requirementsonaudiostreamingbetween
hearingaidsincludeaBERbetterthan
-
Thecommunicationis
simplexwithabitrateofkbitssTheadditionalaudiodecod-
inginthismoderesultsinalongerlatencywhichislessthan
msForremotecontrolcommandstheQoSrequirementsinclude
aBERbetterthan
-
ThelowerBERrequirementresultsfromre-
dundanttransmissionsEachkeypressresultsintransmissionsof
datapackagesofwhichonlyoneisneededforasuccessfulcom-
munication
Forinter-earcommunicationbetweenhearingaidsaBERbetter
than
-
isrequiredThecommunicationisupdatedeveryms
(orHz)Thehearingaidscontinuetoamplifybasedonthelast
savedsettingsevenwhenthetransmissionrangeisexceededor
whencommunicationisinterfered