<xs:simpleType name="ChannelDerivation">
  <xs:annotation>
    <xs:documentation>Specifies the source of data in a channel.</xs:documentation>
  </xs:annotation>
  <xs:restriction base="eml:TypeEnum">
    <xs:enumeration value="raw">
      <xs:annotation>
        <xs:documentation>Raw measured data, directly from sensors.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="simulated">
      <xs:annotation>
        <xs:documentation>Simulated.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="spliced">
      <xs:annotation>
        <xs:documentation>Derived by splicing values from two or more other channels.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="sampled">
      <xs:annotation>
        <xs:documentation>Derived by sampling values from one or more other channels.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
    <xs:enumeration value="model">
      <xs:annotation>
        <xs:documentation>Based on some modeled results of values in another one or more channels.</xs:documentation>
      </xs:annotation>
    </xs:enumeration>
  </xs:restriction>
</xs:simpleType>