<?xml version="1.0" encoding="UTF-8"?>
<!-- edited with XMLSpy v2005 rel. 3 U (http://www.altova.com) by xmlSpy (NA) -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:sopac="http://www.crisisgrid.org/sensorgrid" xmlns:om="http://www.opengis.net/om" xmlns:gml="http://www.opengis.net/gml" targetNamespace="http://www.crisisgrid.org/sensorgrid" elementFormDefault="qualified" attributeFormDefault="unqualified">
	<xs:import namespace="http://www.opengis.net/gml" schemaLocation="includes.xsd"/>
	<xs:import namespace="http://www.opengis.net/om" schemaLocation="richObservation.xsd"/>
	<xs:element name="ObservationCollection" type="sopac:ObservationCollectionType"/>
	<xs:complexType name="ObservationCollectionType">
		<xs:complexContent>
			<xs:extension base="om:ObservationCollectionType"/>
		</xs:complexContent>
	</xs:complexType>
	<xs:element name="PositionMessage" type="sopac:PositionMessageType" substitutionGroup="gml:Observation"/>
	<xs:complexType name="PositionMessageType">
		<xs:complexContent>
			<xs:extension base="om:RichObservationType"/>
		</xs:complexContent>
	</xs:complexType>
	<xs:element name="Site" substitutionGroup="om:Station">
		<xs:complexType>
			<xs:complexContent>
				<xs:extension base="om:TargetObjectType">
					<xs:sequence>
						<xs:element name="SiteCount" type="xs:string" minOccurs="0"/>
						<xs:element name="SiteIndex" type="xs:string" minOccurs="0"/>
					</xs:sequence>
				</xs:extension>
			</xs:complexContent>
		</xs:complexType>
	</xs:element>
	<xs:element name="PositionQuality" substitutionGroup="om:quality"/>
	<xs:complexType name="XYZTPositionType">
		<xs:complexContent>
			<xs:extension base="gml:CompositeValueType"/>
		</xs:complexContent>
	</xs:complexType>
	<!--LatLonHi Position Type-->
	<xs:element name="Position" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="Lat" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Lon" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Height" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<!--XYZT Position Type-->
	<xs:element name="XYZTPosition" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="X" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Y" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Z" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="T" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<!--North/East/Up Position Type-->
	<xs:element name="NEUPosition" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="North" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="East" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Up" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<!--Optional XYZ Variance/Covariance Block-->
	<xs:complexType name="XYZVarianceType">
		<xs:complexContent>
			<xs:extension base="gml:CompositeValueType"/>
		</xs:complexContent>
	</xs:complexType>
	<xs:element name="XYZVarianceBlock" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="Scale" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Xvar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Yvar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Zvar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="YXcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="YZcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="ZXcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<!--Optional Troposhperic Covariance Block-->
	<xs:complexType name="TroposphericCovarianceType">
		<xs:complexContent>
			<xs:extension base="gml:CompositeValueType"/>
		</xs:complexContent>
	</xs:complexType>
	<xs:element name="TroposphericCovarianceBlock" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="Tvar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="TXcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="TYcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="TZcovar" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="SatelliteInfoBlock" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="SatelliteInfo" substitutionGroup="gml:CompositeValue"/>
	<xs:element name="SatelliteCount" substitutionGroup="gml:valueComponent"/>
	<xs:element name="GDOP" substitutionGroup="gml:valueComponent"/>
	<xs:element name="PRN_Value" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="PRNFlags" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Elevation" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
	<xs:element name="Azimuth" type="gml:MeasureType" substitutionGroup="gml:_ScalarValue"/>
</xs:schema>
