php soap .net xml

POST /etl_service/etl_service.asmx HTTP/1.1
Host: 172.21.128.158
Content-Type: text/xml; charset=utf-8
Content-Length: length
SOAPAction: "http://tempuri.org/SFIS_Rv"<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <SFIS_Rv xmlns="http://tempuri.org/">
      <sParam>string</sParam>
      <sWebServiceType>string</sWebServiceType>
    </SFIS_Rv>
  </soap:Body>
</soap:Envelope>
这样一个方法  我该怎么使用php传参，接受返回数据
我的方法require_once('lib/nusoap.php');
$client = new SoapClient(null,array('location'=>'http://172.21.128.158/etl_service/etl_service.asmx','uri'=>'http://172.21.128.158/etl_service/etl_service.asmx')); 
$client->soap_defencoding =  'UTF-8' ;
$client->decode_utf8 =  false ;
$client->xml_encoding =  'UTF-8' ;
$paras = array ( 'sParam' => '[CDATA[<root><METHOD ID=\'INITSO.QryStationUser001\'/>
<STATION_USER>
    <LINE_ID>30</LINE_ID>
    <STATION_ID>47</STATION_ID>
</STATION_USER>
</root>]' ,'sWebServiceType' =>'AKMU2'); $result = $client->call(SFIS_Rv,$paras);
echo $result;
报错
Fatal error: Uncaught SoapFault exception: [soap:Client] Server did not recognize the value of HTTP Header SOAPAction: http://172.21.128.158/etl_service/etl_service.asmx#call. in D:\php\warnings\reception.php:19 Stack trace: #0 [internal function]: SoapClient->__call('call', Array) #1 D:\php\warnings\reception.php(19): SoapClient->call('SFIS_Rv', Array) #2 {main} thrown in D:\php\warnings\reception.php on line 19