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  <xsd:element id="hlit_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="hlit_ShareBasedCompensationInOperatingExpense" name="ShareBasedCompensationInOperatingExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="hlit_StockRepurchaseProgramIncreaseOfCommonStockRepurchaseAuthorization" name="StockRepurchaseProgramIncreaseOfCommonStockRepurchaseAuthorization" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="hlit_StockRepurchasedAndRetiredDuringPeriodSharesAverageCostPerShare" name="StockRepurchasedAndRetiredDuringPeriodSharesAverageCostPerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlit_SwitzerlandMember" name="SwitzerlandMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlit_TransitionServicesAgreementsExpense" name="TransitionServicesAgreementsExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="hlit_USFederalandStateAuthoritiesMember" name="USFederalandStateAuthoritiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="hlit_UnrestrictedCashCashEquivalentsAndShortTermInvestmentsToCurrentLiabilitiesRatio" name="UnrestrictedCashCashEquivalentsAndShortTermInvestmentsToCurrentLiabilitiesRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="hlit_ValueOfStockPurchaseRightPercentageOfCallOption" name="ValueOfStockPurchaseRightPercentageOfCallOption" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="hlit_ValueOfStockPurchaseRightPercentageOfPutOption" name="ValueOfStockPurchaseRightPercentageOfPutOption" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
</xsd:schema>
