Wifi signal strength weak on Ubuntu 18.04 with rtl8723be

I have the Realtek rtl8723be driver on my HP-Pavillion Notebook.

While installing Ubuntu 18.04 LTS through plug-n-play option, I tried the following commands before actual installation:

sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=2

and the wifi was working just fine.

But after installation alongside Windows 10, somehow the wifi stopped working properly, and now only wifi networks very close to the device appear.

I tried installing realtek software from here on GitHub as mentioned in the README. But still no progress.

I even tried changing ant_sel parameters, then saving them to my /etc/modprobe.d/rtl8723be.conf and then performing a cold boot. But still no progress.

I also tried installing from this branch, but I got errors.

sudo lshw -class network
  *-network                 
       description: Wireless interface
       product: RTL8723BE PCIe Wireless Network Adapter
       vendor: Realtek Semiconductor Co., Ltd.
       physical id: 0
       bus info: pci@0000:08:00.0
       logical name: wlo1
       version: 00
       serial: 70:77:81:bf:a7:b9
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=rtl8723be driverversion=4.15.0-36-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11
       resources: irq:18 ioport:5000(size=256) memory:c6100000-c6103fff
  *-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@0000:09:00.0
       logical name: eno1
       version: 0a
       serial: 3c:a8:2a:ba:12:6f
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix 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=rtl8107e-2_0.0.2 02/26/15 latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 ioport:4000(size=256) memory:c6004000-c6004fff memory:c6000000-c6003fff
  *-network
       description: Ethernet interface
       physical id: 3
       logical name: enp0s20u2
       serial: ea:f8:17:e8:82:30
       capabilities: ethernet physical
       configuration: broadcast=yes driver=rndis_host driverversion=22-Aug-2005 firmware=RNDIS device ip=192.168.42.6 link=yes multicast=yes

Can anyone suggest what to do now?

Solution 1:

Please refer to the bug report I linked above at posts #25 and following:

I've tested with the kernel as recommended and suggest in #25. Wifi with rtl8723b3 works again (like a charm). However, ant_sel must be set to 1 (ant_sel=1) as opposed to kernel 4.15.0-32, which required ant_sel to be set to 2 (ant_sel=2). (e.g sudo modprobe rtl8723be ant_sel=1 vs. sudo modprobe rtl8723be ant_sel=2).

At post #32, we see that kernel version 4.17-rc4 works well.

Therefore, I suggest that, if and only if the ant_sel steps don't work, then install the kernel and associated packages. The links are all the usual 64-bit packages. Be certain that yours is a 64-bit install with the terminal command:

arch

If it returns x86_64, then please proceed.

Download these packages:

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17-rc4/linux-headers-4.17.0-041700rc4_4.17.0-041700rc4.201806041713_all.deb

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17-rc4/linux-headers-4.17.0-041700rc4-generic_4.17.0-041700rc4.201806041713_amd64.deb

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17-rc4/linux-image-unsigned-4.17.0-041700rc4-generic_4.17.0-041700rc4.201806041713_amd64.deb

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.17-rc4/linux-modules-4.17.0-041700rc4-generic_4.17.0-041700rc4.201806041713_amd64.deb

By default, downloads go to the folder Downloads. Open a terminal and do:

cd ~/Downloads
sudo dpkg -i linux*.deb

Reboot.

EDIT: Ubuntu 18.10 that was recently released uses kernel version 4.18.0-xx. I assume that rtl8723be will work as expected. You can verify this by running a live session of 18.10. If everything works as expected, I suggest that you install it.