I had the exact same problem with my Ultra. I even performed a factory reset. I took the unit to the service center and they said they needed to replace the main board. I could not accept a repaired $1300 phone, so I asked to replace my unit instead.
Call your country's Samsung hotline. It'll take a while due to the quarantine, but they'll do something.
I have the same issues and i resolved my issue now. The s20 talks to the router on a 5ghz wifi network eventhough it says it is connected to the slower 2.1 ghz. So be sure the 5 ghz network on your router is enabled and be sure you use the 5ghz wifi name ( if you have different wifi network names) . After the reset of the router my speed was the speed of my home network and never saw a drop yet.
Same issue. My s20 doesn't drop the wifi but reduces the speed to under 50 mbs from 800+. I constantly have to turn off wifi and turn it back on to keep the bandwidth up. My wife's 10s does the same thing. Have reset the router's etc. Never had this problem until after the 10s. My note9 that I just traded for the s20 never had this issue. Samsung needs to get this fixed or I'm trading back to my Note9.
I am having this same issue with my Galaxy S20 Ultra. I have issues when connected to my home WIFI which is run through a Google WIFI point. I will loose connection on my phone and when I go into WIFI settings it says the phone is connected to my WIFI without internet. No other device on my network has any issues at all and neither did my Note 10 Plus. My carrier is Straight Talk on AT&T's network (irrelevant) and my Internet provider is Spectrum (irrelevant). This is an obvious issue with the WIFI on the S20.
I had the same problem with my brand new Galaxy S20 Plus. The solution after trying everything else, including reseting my entire phone to factory defaults 3 times, was to replace my 5 year old wireless router. I just went to Walmart and bought a new NetGear AC1600 for $85. Problem solved. No more WiFi drops by the S20 Plus. You can only mix old tech and new tech for so long I guess. :-) It has been over a week and I have had no further issues with the WiFi on the S20 Plus.
I have exactly the same problem
my old samsung s9+ 's wifi work very good but on same time the new one S20 ultra 's wifi connection is very bad i will return back the new s20 ultra
I mean this is the problem with Samsung, seems customer service has absolutely no contact with the software developers and engineers. They will provide you with the " turn on and off" suggestion.....
Anyways my theory is as follows;
Newer models made by Samsung seem to have what is called "wifi scan throttling" which means if you have only a average connection (2-3 bars)you are likely to get sporadic burst errors from interference which can cause the connection to periodically drop. The "wifi scan throttling" prevents the phone from trying to repeatedly scan for devices, I figure they implemented this change in order to limit CPU usage, since each time a scan is conducted an instruction has to be implemented.
Anyways so what happens in these cases is that when a connection is dropped the software is "throttling" the scans which basically means it prevents you from repeatedly scanning for your WiFi device(Router), but of course you need it to rescan since you no longer have any connection.
The work around is as follows(please be very careful not to change other settings unless you know what you are doing)
Initiate developer options as follows ;
Settings>About phone>sofware information
Press the window "build number" 7 times consecutively;
Congrats you have unlocked developer options from settings menu.
Then go to developer options, scroll down to "WiFi scan throttling" and disable the option.
Let me know if that helped and good luck
Thank you for this input. Please keep in mind that altering the development settings can cause your phone to potentially malfunction.