在我的 HP 上安装 ubuntu 16.04 后，我立即发现了 wifi 问题：wifi 范围太弱了，我不得不呆在路由器旁边，否则它会通知connection out of range。所以我在网上搜索，找到了这个指南：http://connectwww.com/how-to-solve-realtek-rtl8723be-weak-wifi-signal-problem-in-ubuntu/4625/
在那里我找到了解决方案，我的互联网开始完美运行。两天前问题又出现了。我尝试按照上一个指南中描述的步骤进行操作，因为我读到每次内核升级后都必须重复此过程，但这次没有奏效。
这是命令的输出sudo lshw -c network，如果您需要它：
*-network
description: Ethernet interface
product: RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:02:00.0
logical name: enp2s0
version: 07
serial: 70:5a:0f:92:e2:9d
size: 10Mbit/s
capacity: 100Mbit/s
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8106e-1_0.0.1 06/29/12 latency=0 link=no multicast=yes port=MII speed=10Mbit/s
resources: irq:124 ioport:4000(size=256) memory:a1200000-a1200fff memory:a1000000-a1003fff
*-network
description: Wireless interface
product: RTL8723BE PCIe Wireless Network Adapter
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:03:00.0
logical name: wlp3s0
version: 00
serial: 44:1c:a8:42:47:8f
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=rtl8723be driverversion=4.4.0-59-generic firmware=N/A ip=192.168.1.5 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
resources: irq:17 ioport:3000(size=256) memory:a1100000-a1103fff
这是输出iwconfig：
wlp3s0 IEEE 802.11bgn ESSID:"Vodafone-26192315"
Mode:Managed Frequency:2.442 GHz Access Point: 00:24:89:79:A8:78
Bit Rate=72.2 Mb/s Tx-Power=20 dBm
Retry short limit:7 RTS thr=2347 B Fragment thr:off
Power Management:off
Link Quality=44/70 Signal level=-66 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:345 Missed beacon:0
enp2s0 no wireless extensions.
lo no wireless extensions.
输出grep [[:alnum:]] /sys/module/rtl8723be/parameters/*
/sys/module/rtl8723be/parameters/ant_sel:2
/sys/module/rtl8723be/parameters/debug:0
/sys/module/rtl8723be/parameters/disable_watchdog:N
/sys/module/rtl8723be/parameters/fwlps:N
/sys/module/rtl8723be/parameters/ips:N
/sys/module/rtl8723be/parameters/msi:N
/sys/module/rtl8723be/parameters/swenc:Y
/sys/module/rtl8723be/parameters/swlps:N