phonegap pass list of conatos to mysql

I'm trying to get the contact list from the phone and send it through ajax and php to mysql. This is the code I'm using:

 document.addEventListener("deviceready", onDeviceReady, false);

    function onDeviceReady() {
        var options = new ContactFindOptions();
        options.filter="";          // empty search string returns all contacts
        options.multiple=true;      // return multiple results
        filter = ["*"]; 
        navigator.contacts.find(filter, onSuccess, onError, options);
    }


function onSuccess(contacts) {  
    for (var i = 0; i < contacts.length; i++){

var phoneNumbers = contacts[i].phoneNumbers;
//alert(JSON.stringify(phoneNumbers));

for (var j=0;j<phoneNumbers.length; j++){
//if(phoneNumbers[j].type == "mobile"){
//alert(phoneNumbers[j].value);

var jsonString = JSON.stringify(phoneNumbers[j].value);


 //var dataString ="title="+jsonString+"&insert=";
 var dataString = JSON.parse(jsonString);


//$("#contactList").append("<li><input type='text' name='box["+i+"]' id='box' value='"+dataString+"'></li>");
$("#contactList").append("<input type='text' name='name[]' id='name' value='"+phoneNumbers[j].value+"'>");
//$("#contactList").listview("refresh");

//}
}
}
}

    function onError(contactError) {
        //alert('onError!');
    }

 AJAX

    var fields = $('#myform').serialize();

    var jsonString = JSON.stringify(fields);
    console.log(fields);
    $.ajax(
    {
        url : "retorno.php",
        type: "POST",
        dataType: "json",
        data: {data : jsonString}, 
        cache: false,
        success:function(data, textStatus, jqXHR) 
        {

$('#stage2').html(data);

        }
    });

});

PHP

$name = $_POST['data'];

If anyone can help, I'll be very grateful.