如何从php推送来自android的通知

嗨我试图从我的PHP网络服务器发送通知到Android手机...但我得到的回应

Unauthorized Error 401

下面是我的代码

 $device_ids , 'data' => $t_data );

$ch = curl_init();

curl_setopt($ch, CURLOPT_HTTPHEADER,$headers );
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode( $t_json ) );
curl_setopt($ch, CURLOPT_URL, $url);
$result = curl_exec($ch);
if ($result === FALSE)
{
 die('Curl failed: ' . curl_error($ch));
}

curl_close($ch);

echo $result;
?>

我该如何解决这个错误