Huawei modem restart

#!/bin/sh
STRING="Connection loss..."
MODEMDEV="/dev/ttyUSB0'
ping -c 2 -s 10 -q 8.8.8.8 > /dev/null
if [ $? = 1 ]; then
    ping -c 6 -s 10 -q 8.8.4.4 > /dev/null
    if [ $? = 1 ]; then
        logger $STRING
        echo -ne "AT+CFUN=1,0\r" > $MODEMDEV
        sleep 3
        echo -ne "AT+CFUN=1,1\r" > $MODEMDEV
    else
        echo "Connection OK." >/dev/null
    fi
else
    echo "Connection OK." >/dev/null
fi