não pode detectar redes wi-fi no Ubuntu 14.04 lts

Question

Eu instalei o 14.04lts do Ubuntu. Mas as redes wi-fi não estão aparecendo. Veja o lado direito onde as redes wi-fi não estão aparecendo, apenas as redes LAN estão aparecendo, o botão habilitar wi-fi não está lá, somente o botão habilitar a rede está lá e, portanto, as redes wi-fi não estão detectando

Como resolver o problema?

lspci

      hpuphy@hpuphy-HP-Compaq-Elite-8300-MT:~$ lspci
      00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core            
      processor DRAM Controller (rev 09)
      00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200     
      v2/3rd Gen Core processor Graphics Controller (rev 09)
      00:14.0 USB controller: Intel Corporation 7 Series/C210 Series   
      Chipset Family USB xHCI Host Controller (rev 04)
      00:16.0 Communication controller: Intel Corporation 7 Series/C216   
      Chipset Family MEI Controller #1 (rev 04)
      00:16.3 Serial controller: Intel Corporation 7 Series/C210 Series 
      Chipset Family KT Controller (rev 04)
      00:19.0 Ethernet controller: Intel Corporation 82579LM Gigabit  
      Network Connection (Lewisville) (rev 04)
      00:1a.0 USB controller: Intel Corporation 7 Series/C216 Chipset  
      Family USB Enhanced Host Controller #2 (rev 04)
      00:1b.0 Audio device: Intel Corporation 7 Series/C216 Chipset Family   
      High Definition Audio Controller (rev 04)
      00:1d.0 USB controller: Intel Corporation 7 Series/C216 Chipset 
      Family USB Enhanced Host Controller #1 (rev 04)
      00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev a4)
      00:1f.0 ISA bridge: Intel Corporation Q77 Express Chipset LPC  
      Controller (rev 04)
      00:1f.2 SATA controller: Intel Corporation 7 Series/C210 Series  
      Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
      00:1f.3 SMBus: Intel Corporation 7 Series/C216 Chipset Family SMBus  
      Controller (rev 04)

$ lshw -C rede

   WARNING: you should run this program as super-user.
   *-network 
   description: Ethernet interface
   product: 82579LM Gigabit Network Connection (Lewisville)
   vendor: Intel Corporation
   physical id: 19
   bus info: pci@0000:00:19.0
   logical name: eth0
   version: 04
   serial: 2c:44:fd:30:c1:48
   size: 1Gbit/s
   capacity: 1Gbit/s
   width: 32 bits
   clock: 33MHz

$ lspci -nnk | grep 0280 -A3
$ rfkill list all
$ 

Não há saída dos comandos lspci -nnk | grep 0280 -A3 e rfkill list all no terminal.

iwconfig

       lo        no wireless extensions.

       eth0      no wireless extensions.

lspci -nnk | grep -iA2 net

    00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit       
    Network Connection (Lewisville) [8086:1502] (rev 04)
    Subsystem: Hewlett-Packard Company Device [103c:3397]
    Kernel driver in use: e1000e