Ubuntu 16.04无线wifi频繁掉线及信号不足解决办法

从安装上ubuntu16.04有好几个月了，每次都会遇到这样的问题：电脑是双系统的，在window系统下连接到同一个wifi信号强，也不掉线。非常稳定，一切换到ubuntu系统就老掉线，掉线就半天连不上。今天在网上查看，终于解决了这个问题！问题处在此版本的系统配备的无线网卡的参数为省电节能模式，信号强度不行。需要修改参数来重启下wifi，就可以了。

1 linuxidc@linuxidc:~$ lspci
 2 00:00.0 Host bridge: Intel Corporation Broadwell-U Host Bridge -OPI (rev 09)
 3 00:02.0 VGA compatible controller: Intel Corporation Broadwell-U Integrated Graphics (rev 09)
 4 00:03.0 Audio device: Intel Corporation Broadwell-U Audio Controller (rev 09)
 5 00:04.0 Signal processing controller: Intel Corporation Broadwell-U Camarillo Device (rev 09)
 6 00:14.0 USB controller: Intel Corporation Wildcat Point-LP USB xHCI Controller (rev 03)
 7 00:16.0 Communication controller: Intel Corporation Wildcat Point-LP MEI Controller #1 (rev 03)
 8 00:1b.0 Audio device: Intel Corporation Wildcat Point-LP High Definition Audio Controller (rev 03)
 9 00:1c.0 PCI bridge: Intel Corporation Wildcat Point-LP PCI Express Root Port #1 (rev e3)
10 00:1c.1 PCI bridge: Intel Corporation Wildcat Point-LP PCI Express Root Port #2 (rev e3)
11 00:1c.2 PCI bridge: Intel Corporation Wildcat Point-LP PCI Express Root Port #3 (rev e3)
12 00:1c.3 PCI bridge: Intel Corporation Wildcat Point-LP PCI Express Root Port #4 (rev e3)
13 00:1c.4 PCI bridge: Intel Corporation Wildcat Point-LP PCI Express Root Port #5 (rev e3)
14 00:1d.0 USB controller: Intel Corporation Wildcat Point-LP USB EHCI Controller (rev 03)
15 00:1f.0 ISA bridge: Intel Corporation Wildcat Point-LP LPC Controller (rev 03)
16 00:1f.2 SATA controller: Intel Corporation Wildcat Point-LP SATA Controller [AHCI Mode] (rev 03)
17 00:1f.3 SMBus: Intel Corporation Wildcat Point-LP SMBus Controller (rev 03)
18 02:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS522A PCI Express Card Reader (rev 01)
19 08:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter
20 09:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller (rev 0a)
21 0a:00.0 3D controller: NVIDIA Corporation GM108M [GeForce 940M] (rev a2)

看到第19行的是无线网卡信息,且型号为RTL8723BE.

从网上看到RTL8723系列网卡都有这个频繁掉线的问题,只不过BE版本是更新的版本,添加了一个参数.

再来查看RTL8723BE这块网卡驱动的参数信息,

1 linuxidc@linuxidc:~$ modinfo rtl8723be
 2 filename:      /lib/modules/4.4.0-22-generic/kernel/drivers/net/wireless/realtek/rtlwifi/rtl8723be/rtl8723be.ko
 3 firmware:      rtlwifi/rtl8723befw.bin
 4 description:    Realtek 8723BE 802.11n PCI wireless
 5 license:        GPL
 6 author:        Realtek WlanFAE    
 7 author:        PageHe    
 8 srcversion:    00619764255210776FAB54D
 9 alias:          pci:v000010ECd0000B723sv*sd*bc*sc*i*
10 depends:        rtlwifi,rtl_pci,btcoexist,mac80211
11 vermagic:      4.4.0-22-generic SMP mod_unload modversions 
12 parm:          swlps:bool
13 parm:          swenc:using hardware crypto (default 0 [hardware])
14  (bool)
15 parm:          ips:using no link power save (default 1 is open)
16  (bool)
17 parm:          fwlps:using linked fw control power save (default 1 is open)
18  (bool)
19 parm:          msi:Set to 1 to use MSI interrupts mode (default 0)
20  (bool)
21 parm:          debug:Set debug level (0-5) (default 0) (int)
22 parm:          disable_watchdog:Set to 1 to disable the watchdog (default 0)
23  (bool)
24 parm:          ant_sel:Set to 1 or 2 to force antenna number (default 0)
25  (int)

看第12行到25行这几个参数,ips和fwlps是用来控制节能的,ant_sel是用来控制信号强度的.最主要的就是修改这几个参数的默认值.

首先我们把配置驱动的文件打开

linuxidc@linuxidc:~$ sudo nano /etc/modprobe.d/rtl8723be.conf

将如下参数黏贴到配置文件中:

options rtl8723be debug=1
options rtl8723be disable_watchdog=N
options rtl8723be fwlps=Y
options rtl8723be ips=Y
options rtl8723be msi=N
options rtl8723be swenc=N
options rtl8723be swlps=N
options rtl8723be ant_sel=2

ctrl+o保存配置文件后,运行如下命令来重启应用，更新wifi配置信息。

linuxidc@linuxidc:~$ sudo modprobe -r rtl8723be
linuxidc@linuxidc:~$ sudo modprobe rtl8723be

是不是信号强了许多?

参考资料：Ubuntu 16.04无线网卡RTL8723BE频繁掉线及信号不足解决办法