安装网络测速工具。此工具为python脚本，可以进行实时测试。
#首次网络测试(仅作为参考使用)
j@j-PC:wget https://raw.githubusercontent.com/sivel/speedtest-cli/master/speedtest.py
j@j-PC:chmod a+rx speedtest.py
j@j-PC:sudo mv speedtest.py /usr/local/bin/speedtest-cli
j@j-PC:sudo chown root:root /usr/local/bin/speedtest-cli
j@j-PC:~$ speedtest-cli
Retrieving speedtest.net configuration...
Testing from China Unicom Liaoning (113.57.165.149)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by ChinaTelecom.Hunan (Changsha) [293.53 km]: 22.236 ms
Testing download speed...............................................................................
.Download: 46.40 Mbit/s
Testing upload speed................................................................................................
Upload: 17.13 Mbit/s

解决方案1：适用于Atheros无线网络适配器中的慢速WiFi(如果您的适配器制造商是Atheros)
j@j-PC:/etc$ sudo lshw -C network
  *-network                 
       description: Ethernet interface
       product: AR8162 Fast Ethernet
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: enp2s0
       version: 10
       serial: 20:89:84:eb:90:f4
       capacity: 100Mbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm pciexpress msi msix bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=alx latency=0 link=no multicast=yes port=twisted pair
       resources: irq:16 memory:d3500000-d353ffff ioport:2000(size=128)
  *-network
       description: Wireless interface
       product: AR9485 Wireless Network Adapter
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:03:00.0
       logical name: wlp3s0
       version: 01
       serial: 48:d2:24:48:38:62
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list rom ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=4.15.0-21deepin-generic firmware=N/A ip=192.168.1.159 latency=0 link=yes multicast=yes wireless=IEEE 802.11
       resources: irq:17 memory:d3400000-d347ffff memory:d3480000-d348ffff
j@j-PC:sudo su
j@j-PC:echo "options ath9k nohwcrypt=1" >> /etc/modprobe.d/ath9k.conf
j@j-PC:Reboot
#第二次网络测试(仅作为参考使用)
j@j-PC:~$ speedtest-cli
Retrieving speedtest.net configuration...
Testing from China Unicom Liaoning (113.57.165.149)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by CHINATelecom.JX (Nanchang) [262.09 km]: 45.268 ms
Testing download speed................................................................................
Download: 31.57 Mbit/s
Testing upload speed................................................................................................
Upload: 20.57 Mbit/s
###########效果不理想###############

解决方案2：禁用802.11n
j@j-PC:sudo rmmod iwlwif
j@j-PC:sudo modprobe iwlwifi 11n_disable=1
j@j-PC:/etc/modprobe.d$ cat iwlwifi.conf
options iwlwifi 11n_disable=1 bt_coex_active=0 power_save=0 auto_agg=0 swcrypto=1
###########Deepin已经设置，此方法忽略###############

解决方案3：修复Debian Avahi-daemon中的错误
hosts:          files dns
j@j-PC:/etc$ cat nsswitch.conf
# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.
passwd:         compat
group:          compat
shadow:         compat
gshadow:        files
hosts:          files mdns4_minimal [NOTFOUND=return] dns
networks:       files
protocols:      db files
services:       db files
ethers:         db files
rpc:            db files
netgroup:       nis
#第三次网络测试(仅作为参考使用)
j@j-PC:~$ speedtest-cli
Retrieving speedtest.net configuration...
Testing from China Unicom Liaoning (113.57.165.149)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by CHINATelecom.JX (Nanchang) [262.09 km]: 68.054 ms
Testing download speed................................................................................
Download: 27.37 Mbit/s
Testing upload speed................................................................................................
Upload: 23.57 Mbit/s
###########有所改善###############

#参照https://itsfoss.com/speed-up-slow-wifi-connection-ubuntu/#

和楼主一样的无线网卡


优化前测速：