A comparison of different wireless LAN transmission techniques using ray tracing

This paper presents a comparison among the performances of various transmission technologies in a typical indoor radio environment. The performance of frequency hopping and direct sequence spread spectrum are compared with the performance of multicarrier, decision feedback equalizer, and sectored antenna systems. Given a maximum tolerable outage probability, the maximum achievable data rates are obtained for the different modulation techniques. Outage probabilities are estimated through simulation, using channel impulse responses obtained from ray tracing. The bandwidth efficiency of spread spectrum modulation is shown be very low. For a fixed bandwidth, the minimum power requirement of each modulation technique is also presented, showing significantly lower power requirements for spread spectrum. Overall, multicarrier modulation is found to present the best tradeoff between bandwidth efficiency and power consumption