Signal strength vs throughput speed question

[magnus17]

I am sharing internet with another household in my neighborhood and the inconsistency in speed is frustrating me. I am using a PC with a D-Link DWL-G520 wireless card installed. Initially when I set up the network I attached a D-Link 6 dBi booster desktop unit which brought in a connection that bounced between 6 Mbps and 11 Mbps and the internet speed was fair but hardly consistent. Download speeds ranged from 10-40 Kps. In an attempt to rectify I removed the 6 dBi booster and installed a professional 12 dBi booster antenna (approx 4 ft long, omni directional w/20 ft cable). This did in fact increase my connection to the network to around 24 Mbps and higher. However, the increased connection to the network did not increase my internet throughput speeds as I had hoped (and in fact has dropped it significantly). Leaving me to wonder what exactly is the relationship between connection speed to the network and throughput speed? I understand that internet traffic on my neighbors end will affect my speed, but are there other factors at work here? Is there any settings I can adjust on my end to improve things?
Your input is appreciated.

[Kashif]

r u using internet through server ? if yes then BW quota system can limit. or else internet provider.

as ur question that 24 mbs connectivity in wireless does provide good speed but u should check ur AP or router that how much packet loss due to signal which can b better through AMP.