My USB network card find no wireless connections..


Code:
root@bt:~# iwlist wlan0 scan

wlan0     No scan results
I checked if it listed in USB devices:


Code:
root@bt:~# lsusb
Bus 007 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 006 Device 002: ID 0bda:8197 Realtek Semiconductor Corp. RTL8187B Wireless Adapter
Bus 006 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 13d3:5702 IMC Networks UVC VGA Webcam
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Then chescked if my iwlist is up to date:
Code:
root@bt:~# iwlist --version
iwlist    Wireless-Tools version 30
          Compatible with Wireless Extension v11 to v22.

Kernel    Currently compiled with Wireless Extension v22.

wlan0     Recommend Wireless Extension v21 or later,
          Currently compiled with Wireless Extension v22.
Then did this thing...
Code:
root@bt:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static

auto eth1
iface eth1 inet dhcp

auto eth2
iface eth2 inet dhcp

auto ath0
iface ath0 inet dhcp

auto wlan0
iface wlan0 inet dhcp

root@bt:~# iwconfig
lo        no wireless extensions.

eth0      no wireless extensions.

wlan0     IEEE 802.11bg  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=off   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:on
But then I run airmon-ng..

Code:
root@bt:~# airmon-ng


Interface	Chipset		Driver

wlan0		Realtek RTL8187BvB	rtl8187 - [phy2]
And this:
Code:
root@bt:~# ifconfig wlan0
wlan0     Link encap:Ethernet  HWaddr 00:24:59:30:0a:c9  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

So, can someone tell me that is the problem? Why it is not picking up any signal?
Even my cell phone picks few, so that is wrong with my wireless card?