Interfacing GPS module mt3333 with 8051

Guys, I'm trying to interface gps module mt3333 with 8051 but unsuccessful til now. My gps module is not showing me proper values in hyper terminal, i.e. it is not showing me latitude or longitude. Also in $GPRMC statement it is showing a letter 'V' which stands for data not valid. So can anyone help me with this so that it shows me latitude and longitude values. Below is what I get in hyperterminal.

PMTK011,MTKGPS*08
$PMTK010,001*2E
$GPGGA,235944.037,,,,,0,0,,,M,,M,,*41
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPRMC,235944.037,V,,,,,0.00,0.00,050180,,,N*48
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32
$GPGGA,235945.036,,,,,0,0,,,M,,M,,*41
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPRMC,235945.036,V,,,,,0.00,0.00,050180,,,N*48
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32
$GPGGA,235946.036,,,,,0,0,,,M,,M,,*42
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPRMC,235946.036,V,,,,,0.00,0.00,050180,,,N*4B
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32
$GPGGA,235947.036,,,,,0,0,,,M,,M
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPRMC,235947.036,V,,,,,0.00,0.00,050180,,,N*4A
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32
$GPGGA,235948.036,,,,,0,0,,,M,,M,,*4C
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGSV,1,1,00*79
$GPRMC,235948.036,V,,,,,0.00,0.00,050180,,,N*45
$GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32

may be that the received signal strength not sufficient.
move it to a different location (open space) and check for reception

Thank you. Moving it to open space helped me. The gps module was able to receive signals when moved to open space. But then how does the GPS in our cellphones work even in indoor places. How is the gps module used to interface with controller different from the one used in our cellphones?

you need to understand GPS signals are not strong as GSM.
GPS usually was made to work on open sky and not indoor buildings.
If you really need to make indoor then consider using active antenna with good gain.