Purposely setting poor Signal Quality on my own WiFi
Solution 1:
This depends entirely on your access point hardware.
For example, on Tomato firmware go to Advanced -> Wireless -> Transmit Power and set a new value to lower the signal strength.
Another (possibly better approach) would be to add rules into your local firewall to manipulate the traffic parameters.
For example if you're on Linux, iptables -t mangle -A INPUT -m statistic --mode random --probability 0.01 -j DROP introduces an average of a 1% packet loss.
Solution 2:
Give it a tinfoil hat? :)