networking – Poor Wifi Signal Strength on Dell Latitude Laptop with Ubuntu 20.04

Wifi signal strength is moderate at 3 meters from the router with no obstacles in the middle. The signal strength reduces if I move to 5 meters; and if I move to the next room, wifi disconnects. This laptop did not have a wifi problem with Windows installed. The Dell latitude laptop has ubuntu 20.04. I tried setting the ant_sel to 1 for iwlwifi and that did not help. The laptop uses Intel 3165 for wireless interface.

>sudo lshw -C network
  *-network                 
       description: Wireless interface
       product: Wireless 3165
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:06:00.0
       logical name: wlp6s0
       version: 79
       serial: 70:1c:e7:16:c2:cc
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=iwlwifi driverversion=5.4.0-42-generic firmware=29.1654887522.0 ip=192.168.1.112 latency=0 link=yes multicast=yes wireless=IEEE 802.11
       resources: irq:50 memory:f7100000-f7101fff```

#Link Quality at 3 Meters:

>iwconfig
wlp6s0    IEEE 802.11  ESSID:"swshaabsnl"  
          Mode:Managed  Frequency:2.417 GHz  Access Point: 34:E8:94:53:E9:48   
          Bit Rate=21.7 Mb/s   Tx-Power=22 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=19/70  Signal level=-91 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:49   Missed beacon:0

>uname -av
Linux aniruddha-Latitude-3560 5.4.0-42-generic #46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Thanks for your help!