EV-DO with Pantech px-500 with sprint in linux. to get signal strenght,
echo at+csq |socat - /dev/ttyACM0,raw,echo=0,crnl
if you dont have socat, you can just do it in minicom. 

-- pppdscript.sh --
#!/bin/sh

USER="yournamehere@sprintpcs.com"
CHATSCRIPT="/etc/ppp/peers/1xevdo_chat"
DEV="/dev/ttyACM0"
SPEED="115200"

TEMPLOG=/tmp/pppd-$$
rm /tmp/pppd-*
echo TEMPLOG is $TEMPLOG

PPPOPTS=$DEV
PPPOPTS="$PPPOPTS $SPEED"
PPPOPTS="$PPPOPTS user $USER"
PPPOPTS="$PPPOPTS debug"
PPPOPTS="$PPPOPTS noauth"
PPPOPTS="$PPPOPTS nodetach"
PPPOPTS="$PPPOPTS defaultroute"
PPPOPTS="$PPPOPTS usepeerdns"
PPPOPTS="$PPPOPTS connect-delay 10000"
PPPOPTS="$PPPOPTS crtscts"
PPPOPTS="$PPPOPTS persist"
PPPOPTS="$PPPOPTS lock"
PPPOPTS="$PPPOPTS lcp-echo-failure 4"
PPPOPTS="$PPPOPTS lcp-echo-interval 65535"

/sbin/route delete default
/usr/sbin/pppd $PPPOPTS connect "/usr/sbin/chat -v -t3 -f $CHATSCRIPT" > $TEMPLO
G &
PPPD_PID=$!

echo -n waiting
while ! grep DNS $TEMPLOG;do
        echo -n .
        sleep 1
done
echo

DNS1=`grep primary $TEMPLOG | grep DNS | awk '{print $4}'`
DNS2=`grep secondary $TEMPLOG | grep DNS | awk '{print $4}'`

cat > /etc/resolv.conf <<EOF
# dumped here by $0
nameserver $DNS1
nameserver $DNS2
EOF

-- chatscript --

'' 'AT'
'OK' 'ATE0V1&F&D2&C1&C2S0=0'
'OK' 'ATE0V1'
'OK' 'ATS7=60'
'OK' 'ATDT#777'

when you use noauth, pppd wants to only be run as root. you can use sudo, but setuid wont work.