$re = '/^(?<device>{[^^]*})\^(?<topic>{[^^]*})\^(?<payload>.*)$/m';
$str = '{"r":"presenter_id","s":"client0_id","id":"3961825726-request"}^{"requestId":"3961825726","route":"/basic/handshake/join","role":"request"}^{"playerName":"Marta"}';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php