一段时间以来，我的多个网络的 wifi 连接一直很慢，我想这要从我更新到 12.04 版本开始。我尝试了论坛上已有的许多提示和技巧，但都没有成功（wicd 等）。我想看看你们这些专家是否能帮助我，提前谢谢大家！！
我在联想 ideapad y650 上使用 ubuntu 12.04，我连接的大多数网络经常断开连接或者在连接时没有提供适当的带宽。
以下是一些常规系统检查的结果：
cat /etc/lsb-release; uname -a：
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=12.04
DISTRIB_CODENAME=precise
DISTRIB_DESCRIPTION="Ubuntu 12.04.2 LTS"
Linux mgeorge-lenovo 3.2.0-48-generic-pae #74-Ubuntu SMP Thu Jun 6 20:05:01 UTC 2013 i686 i686 i386 GNU/Linux
请参阅lspci-nnk| grep -iA2 网：
04:00.0 Network controller [0280]: Intel Corporation PRO/Wireless 5100 AGN [Shiloh]
Network Connection [8086:4237]
Subsystem: Intel Corporation WiFi Link 5100 AGN [8086:1211]
Kernel driver in use: iwlwifi
--
08:00.0 Ethernet controller [0200]: Broadcom Corporation NetLink BCM5784M Gigabit Ethernet PCIe [14e4:1698] (rev 10)
Subsystem: Lenovo Device [17aa:3878]
Kernel driver in use: tg3
lsusb：
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 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 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 008 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 002: ID 090c:7371 Silicon Motion, Inc. - Taiwan (formerly Feiya Technology Corp.)
配置：
lo no wireless extensions.
wlan0 IEEE 802.11abgn ESSID:"Dyno"
Mode:Managed Frequency:2.412 GHz Access Point: CC:5D:4E:46:0A:93
Bit Rate=150 Mb/s Tx-Power=15 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=70/70 Signal level=-40 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:948 Invalid misc:728 Missed beacon:0
eth0 no wireless extensions.
rfkill 列出全部：
0: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
1: ideapad_bluetooth: Bluetooth
Soft blocked: yes
Hard blocked: no
2: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
lsmod：
Module Size Used by
uvcvideo 67203 0
videodev 86588 1 uvcvideo
nouveau 712674 3
ttm 65344 1 nouveau
drm_kms_helper 45466 1 nouveau
drm 197641 5 nouveau,ttm,drm_kms_helper
i2c_algo_bit 13199 1 nouveau
mxm_wmi 12893 1 nouveau
wmi 18744 1 mxm_wmi
joydev 17393 0
arc4 12473 2
snd_hda_codec_realtek 174313 1
snd_hda_codec_hdmi 31775 1
snd_hda_intel 32719 3
snd_hda_codec 109562 3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel
snd_hwdep 13276 1 snd_hda_codec
snd_pcm 80916 3 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec
snd_seq_midi 13132 0
snd_rawmidi 25424 1 snd_seq_midi
snd_seq_midi_event 14475 1 snd_seq_midi
psmouse 86520 0
snd_seq 51592 2 snd_seq_midi,snd_seq_midi_event
serio_raw 13027 0
snd_timer 28931 2 snd_pcm,snd_seq
snd_seq_device 14172 3 snd_seq_midi,snd_rawmidi,snd_seq
iwlwifi 366509 0
mac80211 436493 1 iwlwifi
snd 62218 16
snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,sn
d_rawmidi,snd_seq,snd_timer,snd_seq_device
ideapad_laptop 17890 0
sparse_keymap 13658 1 ideapad_laptop
cfg80211 178877 2 iwlwifi,mac80211
ir_lirc_codec 12739 0
lirc_dev 18700 1 ir_lirc_codec
soundcore 14635 1 snd
snd_page_alloc 14108 2 snd_hda_intel,snd_pcm
ir_mce_kbd_decoder 12681 0
ir_sony_decoder 12462 0
ir_jvc_decoder 12459 0
ir_rc6_decoder 12459 0
ir_rc5_decoder 12459 0
rc_rc6_mce 12454 0
ir_nec_decoder 12459 0
video 19115 1 nouveau
ene_ir 18019 0
rc_core 21263 10
ir_lirc_codec,ir_mce_kbd_decoder,ir_sony_decoder,ir_jvc_decoder,ir_rc6_decoder,ir_rc5_decoder,rc_rc6_mce,ir_nec_decoder,ene_ir
bnep 17830 2
rfcomm 38139 0
parport_pc 32114 0
bluetooth 158479 10 bnep,rfcomm
ppdev 12849 0
binfmt_misc 17292 1
mac_hid 13077 0
lp 17455 0
parport 40930 3 parport_pc,ppdev,lp
tg3 141414 0
nm 工具：
NetworkManager Tool
State: connected (global)
- Device: eth0 -----------------------------------------------------------------
Type: Wired
Driver: tg3
State: unavailable
Default: no
HW Address: 00:23:5A:CC:85:BD
Capabilities:
Carrier Detect: yes
Wired Properties
Carrier: off
- Device: wlan0 [Dyno] --------------------------------------------------------
Type: 802.11 WiFi
Driver: iwlwifi
State: connected
Default: yes
HW Address: 00:22:FA:D0:94:CA
Capabilities:
Speed: 150 Mb/s
Wireless Properties
WEP Encryption: yes
WPA Encryption: yes
WPA2 Encryption: yes
Wireless Access Points (* = current AP)
*Dyno: Infra, CC:5D:4E:46:0A:93, Freq 2412 MHz, Rate 54 Mb/s, Strength 81 WPA2
IPv4 Settings:
Address: 10.0.0.43
Prefix: 24 (255.255.255.0)
Gateway: 10.0.0.1
DNS: 10.0.0.1
答案1
无线-N 存在一个常见的错误，因此我们必须禁用它。
请尝试以下操作：
sudo modprobe -r iwlwifi && sudo modprobe iwlwifi 11n_disable=1
检查您的无线速度。如果速度有所改善，请执行以下操作以使速度保持稳定：
sudo sh -c 'echo "options iwlwifi 11n_disable=1" >> /etc/modprobe.d/iwlwifi.conf'