Convert sound for Asterisk Mp3 to Wav

$i = 0;
while ($i <= 101)
{
$i++;
shell_exec(«lame —decode /tmp/mp3/$i.mp3 — | sox -v 0.5 -t wav — -t wav -b 16 -r 8000 -c 1 /tmp/wav/1/$i.wav»);
}