Here is how to convert UCS-2 numbers to UTF-8 numbers in hex:

<?php
function ucs2toutf8($str)
{
        for ($i=0;$i<strlen($str);$i+=4)
        {
                $substring1 = $str[$i].$str[$i+1];
                $substring2 = $str[$i+2].$str[$i+3];
 
                if ($substring1 == "00")
                {
                        $byte1 = "";
                        $byte2 = $substring2;
                }
                else
                {
                        $substring = $substring1.$substring2;
                        $byte1 = dechex(192+(hexdec($substring)/64));
                        $byte2 = dechex(128+(hexdec($substring)%64));
                }
                $utf8 .= $byte1.$byte2;
        }
        return $utf8;
}
 
echo strtoupper(ucs2toutf8("06450631062D0020"));

?>

Input:
06450631062D
Output:
D985D8B1D8AD

regards,
Ziyad