Optimum Parameters for Maximum Throughput of FHMA System With Multilevel FSK
Kwonhue Choi, Kyungwhoon Cheun · IEEE Transactions on Vehicular Technology · 2006
The authors optimize system parameters including modulation order M, diversity order L, and traffic density lambda to maximize the throughput of frequency-hopping-multiple-access networks with multilevel frequency-shift keying. It is shown that optimal lambda is close to ln 2 with the exception that optimal lambda=1 for the erasures coding channel with M=2. For the erasures coding channel, optimum L is also derived, and for the hard-decision coding channel, optimum L is numerically searched. For the region of M64, the hard-decision coding channel achieves slightly higher throughput than the erasures coding channel. While the maximum throughput for the hard-decision coding channel monotonously increases as M increases, the maximum throughput for the erasures coding channel shows a local increase at M=2, and it is significantly higher than that for the hard-decision coding channel with M=2. Tradeoffs between system parameters to achieve the maximum throughput under a fixed bandwidth constraint are also presented. It is shown that the optimal set for (M,L,N(=number of available frequencies)) is approximately (G,log2G,G) for both coding channels, where G is the total system bandwidth expansion normalized by bit rate