A High Data-rate Wireless Local Area Network using Spread Spectrum Communication for Network Control
Kohji Itoh, Makoto Itami · 1994
The paper proposes a high data rate packet wireless LAN system using spread spectrum (SS) communication for network control and channel measurement purposes. The packet data (PD) transmission employs demand-and-assign protocol and ordinary DPSK modulation with its receiver performance being enhanced by the maximum likelihood sequence estimation (MLSE) scheme. The MLSE scheme is provided with the channel characteristics estimated in real time by the SS communication. The SS communication has to be periodically inserted in coarse time division with the PD transmission. Assuming 16 node network, 10 Mbps PD transmission and a typical power-delay profile data of the in-office IMS band propagation, sample design choices of the access and routing protocols are proposed. The performances of PD transmission with MLSE reception were analysed both by simulation and theory. What is found most remarkable with MLSE scheme is that the norm of the channel tap weight vector, and not the vector itself, is an almost complete measure of expected quality in terms of bit error probability. The quality rating of 10-' bit error probability is seen to be guaranteed for 99.94% of the run time, assuming one hop detour routing capability.