Problem
1. If the received signal power is 2 mW for a mobile user who is 500 m from a particular base station, use the inverse-fourth power relationship to find an approximation for the received signal power for a mobile user that is 2 km from the same base station. Show your working to obtain full marks.
2. If a 8 MB file is compressed using a compression ratio of 4 and then downloaded over a 50 Mbps internet connection, approximately how long would the download take? Give your answer to 2 significant figures. (You should assume that no error control is being used and that file size is a multiple of 2 in your calculation). Show your working to obtain full marks.
3. Providers of a wireless network claim a theoretical maximum data rate of 2 Gbps. This is when the network is using 1024-QAM modulation. In reality, however, 256-QAM is used most of the time. Based on the actual modulation scheme that is typically used, and if the throughput of the system is 75%, what is the actual data rate that can be expected? Show your working to obtain full marks.